Linear Positioning Module Cat. No.
Important User Information Because of the variety of uses for the products described in this publication, those responsible for the application and use of this control equipment must satisfy themselves that all necessary steps have been taken to assure that each application and use meets all performance and safety requirements, including any applicable laws, regulations, codes and standards.
Table of Contents Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P 1 Organization of the Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Audience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Related Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Related Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Frequently Used Terms . . . . . . . . . . . .
ii Table of Contents Hardware Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1 Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Wiring Arm Terminals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Transducer Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Determining the Optimum Number of Circulations . . . . . . . . . . . . . Discrete Inputs . . . . . . . . . . . . . . . . . . . . . . . . .
Table of Contents iii Connecting the Analog Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Analog Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Connecting the Discrete Outputs . . . . . . . . . . . . . . . . . . . . . . . . . Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . OUTPUT 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
iv Table of Contents Gain Factor (words 19 and 48) . . . . . . . . . . . . . . . . . . . . . . . . Integral Gain (words 20 and 49) . . . . . . . . . . . . . . . . . . . . . . . Derivative Gain (words 21 and 50) . . . . . . . . . . . . . . . . . . . . . . Feedforward Gain (words 22 and 51) . . . . . . . . . . . . . . . . . . . . Global Velocity (words 23 and 52) . . . . . . . . . . . . . . . . . . . . . . Global Acceleration/Deceleration (words 24, 25 and 53, 54) . . . .
Table of Contents v Using the Motion Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 12 Sample Application Programs . . . . . . . . . . . . . . . . . . . . . . 10 1 Programming Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Block Transfer Sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PLC 5 Block Transfer Instructions . . . . . . . . . . . . . . . . . . . . . . . . Application Program #1 . . . . . . . . . . . . . . . . . . . . . .
vi Table of Contents Data Formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . H 1 BCD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2's Complement Binary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bit Inversion Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Subtraction Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Implied Decimal . . . . . . . . . . . . . . . . . .
Preface Preface This manual explains how to install and configure the Linear Positioning Module. It includes sample application programs to illustrate how to program a PLC to work with the Linear Positioning Module.
Preface Chapter Audience Title Describes: Appendix E Command Block command block word assignments Appendix F Motion Block motion block word assignments Appendix G Hexadecimal Data Table Form hexadecimal data worksheets Appendix H Data Formats valid data formats Appendix I Product Specifications 1771 QB product specifications Read this manual if you intend to install or use the Linear Positioning Module (Cat. No. 1771-QB).
Preface Frequently Used Terms Appendix A contains a complete glossary of terms and abbreviations used in this manual. To make this manual easier for you to read and understand, product names are avoided where possible. The Linear Positioning Module is also referred to as the “module”.
Chapter 1 Introducing the Linear Positioning Module What is the Linear Positioning Module? The Linear Positioning Module (Cat. No. 1771-QB) is a dual-loop position controller occupying a single slot in the Allen-Bradley 1771 Universal I/O chassis. It can control servo or proportional hydraulic valves, or some electric servos. Position is measured with a linear displacement transducer. You use the module to control and monitor the linear position of a tool or workpiece along one or two axes. Figure 1.
Chapter 1 Introducing the Linear Positioning Module Product Compatibility PLCs You can use the module with any Allen-Bradley PLC that uses block transfer programming in local 1771 I/O systems including: PLC-2 family PLC-3 family PLC-5 family - PLC-5/10 (Cat. No. 1785-LT4) - PLC-5/11 (Cat. No. 1785-LT11) - PLC-5/12 (Cat. No. 1785-LT3) - PLC-5/15 (Cat. No. 1785-LT) - PLC-5/20 (Cat. No. 1785-L20) - PLC-5/25 (Cat. No. 1785-LT2) - PLC-5/30 (Cat. No. 1785-L30) - PLC-5/40 (Cat. No.
Chapter 1 Introducing the Linear Positioning Module Santest Co. Ltd. c/o Ellis Power Systems 123 Drisler Avenue White Plains, NY 10607 (914) 592-5577 Lucas Schaevitz Inc. 7905 N. Route 130 Pennsauken, NJ 08110-1489 (609) 662-8000 All four manufacturers provide versions of the transducer that connect directly to the module’s wiring arm, without an external digital interface box. The module may also be compatible with other linear displacement transducers.
Chapter 1 Introducing the Linear Positioning Module System Overview Figure 1.2 shows one of the module’s two control loops within a linear positioning system for closed-loop axis control. The module communicates with a programmable controller through the 1771 backplane. The programmable logic controller sends commands and user-programmed data from the data table to the module as directed by a block-transfer write instruction. Figure 1.
Chapter 1 Introducing the Linear Positioning Module The module also connects to linear displacement transducers (one for each of the two axes) via wiring arm terminals. The transducer senses the axis position and feeds it back to the module, thereby closing the control loop. The module’s built-in processor samples the linear displacement transducer interfaces and determines positions along each of the two axes every two milliseconds.
Chapter 2 Positioning Concepts This chapter explains concepts and principles of axis positioning. If you are thoroughly familiar with the concepts of closed-loop servo positioning, you can go on to Chapter 3. Axis Motion Figure 2.1 illustrates a typical method of converting the flow of fluid into a linear displacement. Figure 2.
Chapter 2 Positioning Concepts Closed Loop Positioning Closed-loop positioning is a precise means of moving an object from one position to another. In a typical application, a positioning device activates a servo valve controlling the movement of fluid in a hydraulic system. The movement of fluid translates into the linear motion of a hydraulic cylinder. A transducer monitors this motion and feeds it back to the positioning device.
Chapter 2 Positioning Concepts Figure 2.3 Circulations resolution = 0.002 Gate (received from transducer) Duration (1 circulation) resolution = 0.001 Gate (received from transducer) Duration (2 circulations) 50035 A Simple Positioning Loop To move a specified distance along an axis, you can command the hydraulic device to move at a specific velocity for a specific length of time. However, this method can be imprecise.
Chapter 2 Positioning Concepts In Figure 2.
Chapter 2 Positioning Concepts Feedforwarding To decrease the following error without increasing the gain, you can add a feedforward component. (See Figure 2.5.) Figure 2.5 Positioning Loop with Feedforwarding KF Desired Velocity sdt Integrator Following Error Position Command + Kp Feed Forward + Velocity Command + - Servo Valve D/A Axis Actual Position sdt Linear Displacement Transducer 50037 Feedforwarding requires an additional summing point and an amplifier.
Chapter 2 Positioning Concepts Without integral control, the axis responds only to the size of the positioning error, not its duration. Integral control responds to both the size and duration of the positioning error. Thus, the integral term continues to adjust the velocity command until it achieves an exact correction. When you increase the integral gain (KI), you increase the rate at which the positioning loop responds to a following error. However, the capabilities of the system limit gain KI.
Chapter 2 Positioning Concepts Figure 2.7 Derivative Control KF Feed Forward Integrator Desired Velocity sdt Integrator Following Error Position Command + KI sdt + Kp - Derivative Actual Position KD d dt + + + Velocity Command + Servo Valve D/A Axis Linear Displacement Transducer sdt 50039 Deadband Most systems have friction and play in their mechanical linkages.
Chapter 2 Positioning Concepts You can control the integral and derivative components by defining a PID (proportional, integral and derivative) band. The PID band is a region surrounding the programmed endpoint where the system enables integral or derivative terms. As a result, the integral and derivative components affect only the final positioning of the axis.
Chapter 3 Positioning with the Linear Positioning Module This chapter explains how the Linear Positioning Module interacts with a programmable controller to control axis movement within a linear positioning system. How the Module Fits in a Positioning System Figure 3.1 shows how the module functions in a typical positioning system. Note that the positioning loop closes in the module and functions independently of the programmable controller’s I/O scan rate.
Chapter 3 Positioning with the Linear Positioning Module How the Module Interacts with a PLC The module is a dual-loop position controller, occupying a single slot in the Allen-Bradley 1771 universal I/O chassis. The module communicates with the PLC through the 1771 backplane. There are two kinds of transfers–read operations and write operations. By programming the PLC you can transfer parameter, setpoint, motion and command blocks to the module to control the two axes.
Chapter 3 Positioning with the Linear Positioning Module Figure 3.2 Trapezoidal Axis Movement Velocity Constant Velocity Final Velocity Acceleration Deceleration Time Start 0 Finish 50002 The actuator may not reach the final velocity during a short move which may only consist of acceleration and deceleration phases without a constant velocity phase. This produces a ramp movement. (See Figure 3.3.) Figure 3.
Chapter 3 Positioning with the Linear Positioning Module Figure 3.4 Axis Movement with Velocity Curve Smoothing Velocity Constant Velocity Final Velocity 0 Acceleration Deceleration Start Finish Time Acceleration Final Accel 0 Final Decel Deceleration Commanding Motion Finish Start Time 50004 There are three ways to specify module axis motion: by setpoints, by jogging or by motion blocks. All motion must be started using the command block and/or hardware inputs.
Chapter 3 Positioning with the Linear Positioning Module turn on a hardware start enable bit (using the command block), which causes the module to delay movement to the commanded setpoint. The delay ends and movement starts when you activate the hardware start input or send a software start command in the command block. command a setpoint while the axis is moving towards another setpoint.
Chapter 4 Hardware Description This chapter describes the Linear Positioning Module hardware, as well as other hardware required for a positioning system. Indicators Figure 4.1 shows the three indicators on the module. Figure 4.1 Indicators LINEAR POSITIONING FAULT LOOP1 ACTIVE LOOP2 ACTIVE 50009 When you first power up the module, all three indicators turn on for about one second. Next, the LOOP 1 ACTIVE and LOOP 2 ACTIVE indicators turn off while the module performs diagnostics.
Chapter 4 Hardware Description Wiring Arm Terminals The module draws power for its internal circuitry and communicates with the programmable controller through the 1771 universal I/O chassis. You make all other connections through the wiring arm terminals. Cable length can be up to 200 feet for these connections, depending on the gauge used. See Chapter 5 for wiring guidelines. Figure 4.2 shows the wiring arm terminals for both control loops. Figure 4.
Chapter 4 Hardware Description analog output interface terminals discrete output terminals The terminals for these four groups are divided between loop 1 and loop 2. Odd number terminals are for loop 1; even numbered terminals apply to loop 2. Transducer Interface Terminals 1 through 8 on the module’s wiring arm provide connection points for the transducer interface. The module is designed to work with the linear displacement transducers (LDT) listed in Chapter 1.
Chapter 4 Hardware Description Use these equations to determine the maximum length and positioning resolution for the transducer: maximum length = 1680/(T x N) resolution = 1/(58.5 x T x N) where: T = transducer constant stamped on transducer head (typically 9.0500 microseconds per inch) N = number of circulations The following table gives several maximum transducer lengths assuming a transducer constant of 9.0500 microseconds per inch.
Chapter 4 Hardware Description Discrete Inputs Terminals 13 through 26 on the module’s wiring arm provide connection points for discrete input signals. Seven terminals (for each loop) connect to seven discrete inputs. The use of these inputs is optional. If you do not want to use them, you can disable them through the parameter block. (See Chapter 7.
Chapter 4 Hardware Description Figure 4.3 Simplified Schematic of a Discrete Input 1771 - QB MODULE 27 INPUT SUPPLY + 5V 10K DISCRETE INPUT (e.g. JOG FWD) 3.3K 28 INPUT COMMON 50041 Auto/Manual Input The module accepts the signal at the AUTO/MAN terminal (13/14) as the auto/manual input. Use this input in conjunction with block transfers to set the operation mode for the axis. A high input means auto mode and a low input means manual mode.
Chapter 4 Hardware Description Hardware Stop Input The module accepts the signal at the STOP terminal (17/18) as a low-true hardware stop input. A low signal at the hardware stop input disables the analog output and stops axis movement. Unless the discrete inputs are disabled via the parameter block, this input must be high for normal operation. If the connection breaks, axis movement stops.
Chapter 4 Hardware Description The analog output interface circuit is electrically isolated from the 1771 I/O chassis. This feature protects other devices on the 1771 backplane from noise and current surges in the analog output circuit. An internal relay automatically shuts off these outputs in the event of a module fault. For details on connecting the servo valve interface, see Chapter 5.
Chapter 4 Hardware Description Important: If you want to connect a discrete output of one axis to the discrete input of another axis, the minimum discrete output supply voltage is 11.6 VDC. This accounts for the voltage drop of 1.6 VDC shown above and provides the minimum voltage required to drive a module discrete input (10 VDC). ATTENTION: The discrete outputs can withstand a short circuit for a few seconds. However, a continuous short circuit will damage the module’s discrete output transistor.
Chapter 4 Hardware Description to power the: supply: to these terminals: Transducer interface +5 VDC 9, 10 Discrete inputs +24 VDC (max) 27, 28 Servo valve interface +15 VDC 33, 34, 35 Discrete outputs +30 VDC (max) 40 All power connections must be made for the transducer, servo valve, and discrete outputs. The power supply for discrete inputs may be left unconnected if the discrete input disable bit has been set in the parameter block.
Chapter 5 Installing the Linear Positioning Module Before You Begin This chapter tells you how to install the module in the I/O chassis and how to configure the module’s analog outputs by setting DIP switches.
Chapter 5 Installing the Linear Positioning Module Electrostatic Discharge Under some conditions, electrostatic discharge can degrade performance or damage the module.
Chapter 5 Installing the Linear Positioning Module Figure 5.1 Locating the Analog Configuration Switches LOOP 2 CURRENT RANGE VOLTAGE/CURRENT LOOP 1 CURRENT RANGE VOLTAGE/CURRENT 50043 2. Use a blunt pointed instrument (such as a ballpoint pen) to set the switches. ATTENTION: Don’t use a pencil to set switches. Lead can jam the switch.
Chapter 5 Installing the Linear Positioning Module 3. Set the current/voltage switch for each control loop as shown in Figure 5.2. Figure 5.2 Configuring the Analog Outputs LOOP 1 1 C1 1 C2 LOOP 2 2 2 OPEN 1 C1 1 2 2 C2 OPEN 1771 QB Chassis 1 C1 1 2 2 OPEN C2 ±100mA C1 1 TYPES OF SWITCHES ON ON ON ± 50mA ± 20mA ± 10V 1 2 OPEN C1 C2 2 2 C2 1 1 OPEN C1 ROCKER TOGGLE 2 2 C2 1 SLIDE 1 2 OPEN The range selection switches have no effect when ±10V is selected. 50044 4.
Chapter 5 Installing the Linear Positioning Module Keying A package of plastic keys (Cat. No. 1771-RK) is provided with every I/O chassis. When properly installed, these keys prevent the seating of anything but the module in the keyed I/O chassis slot. Keys also help to align the module with the backplane connector. Each module is slotted at its rear edge. Position the keys on the chassis backplane connector, corresponding to the slots on the module’s rear edge.
Chapter 5 Installing the Linear Positioning Module 2. Open the module locking latch on the I/O chassis and insert the module into the slot keyed for it. 3. Press firmly to seat the module into the backplane connector. 4. Secure the module with the module locking latch. ATTENTION: Don’t force a module into the backplane connector. If you can’t seat a module with firm pressure, check the alignment and keying. Forcing a module can damage the backplane connector and the module.
Chapter 5 Installing the Linear Positioning Module Figure 5.4 Shielded Cable Grounding Connections Transducer Supply 5 LINEAR POSITIONING Transducer FAULT 4 LOOP1 ACTIVE LOOP2 ACTIVE 1 2 2 Discrete Input Supply 3 5 Analog Supply Discrete Output Supply 2 2 Shielded cables are not required for these discrete inputs and outputs. However, they can improve noise immunity. I/O Chassis Ground Bus 1 2 3 4 5 Servo Valve 8 AWG wire to central ground bus Belden 8723 or equivalent (50 ft. max.
Chapter 5 Installing the Linear Positioning Module Using Twisted Wire Pairs It is recommended you use twisted wire pairs for a signal and its return path to reduce noise levels further. Figure 5.5 shows a twisted pair and shielded twisted pair. Figure 5.5 Shielded Twisted Pair Diagram Twisted Pair Shielded Twisted Pair 50046 ATTENTION: Failure to follow correct shielding procedures can cause unpredictable movement resulting in possible injury to personnel and damage to equipment.
Chapter 5 Installing the Linear Positioning Module Figure 5.
Chapter 5 Installing the Linear Positioning Module Power Supplies The 1771 backplane provides the power for most of the module circuits. You’ll need external power supplies for the analog outputs, transducer interfaces, discrete inputs and discrete outputs. All four power supplies and their associated module circuits are electrically isolated from the I/O chassis and from each other. To provide maximum isolation of the four sets of circuits, the four supplies should be from separate sources.
Chapter 5 Installing the Linear Positioning Module Figure 5.7 Transducer Connections LOOP 2 TRANSDUCER LOOP 1 TRANSDUCER Connect to Transducer Head 5 - + 4 +5 Com Transducer Supply (Customer Supplied) Ground the shield at the I/O chassis end. Wiring Arm Terminals 1 LOOP 2 2 4 6 8 10 +GATE -GATE +INTERR -INTERR +5 COMMON 1 LOOP 1 +GATE -GATE +INTERR -INTERR +5 VDC 1 3 5 7 9 Ground the shield at the I/O chassis end. Ground the shield at the I/O chassis end.
Chapter 5 Installing the Linear Positioning Module 3. Connect - VDC from your power supply to the transducer. 4. Connect the common terminal on your power supply to the +5 COMMON terminal (10) on the module, to ground at the I/O chassis, and to the transducer. 5. Connect the cable shields to ground at the I/O chassis end. 6. Connect the power supply chassis to ground. Transducer Interface After connecting the transducer power supply to the module, make the Gate and Interrogate connections.
Chapter 5 Installing the Linear Positioning Module Make sure that the voltage driving each input is at the appropriate level. Figure 5.8 shows the discrete input connections. Figure 5.
Chapter 5 Installing the Linear Positioning Module Power Supply To connect the discrete input power supply, follow these steps: 1. Connect the (+) side of the discrete input power supply to the I/P SUPPLY terminal (27) of the module. 2. Connect the common of the discrete input power supply to the I/P COMMON terminal (28) of the module. 3. Connect the cable shield to ground at the I/O chassis end. 4. Connect the power supply chassis to ground.
Chapter 5 Installing the Linear Positioning Module ATTENTION: In servo valve control systems, axis drift may occur due to imprecise valve nulling even with zero analog output. It is recommended that emergency stop switches, such as overtravel limit switches, also turn off axis power and close a blocking valve installed between the servo valve and the prime mover.
Chapter 5 Installing the Linear Positioning Module Jog Reverse Input The jog reverse input is valid only in the manual mode. The jog reverse input is similar to the jog forward input, except the axis movement is in the reverse direction (the direction of negative movement relative to the zero-position offset). Connect the JOG REV terminal (21/22) in the same way as the jog forward input. Leave the terminal disconnected if you are not using it.
Chapter 5 Installing the Linear Positioning Module Pull-down resistors or double-throw switches are only required if you wish to connect two or more QB’s. They are not required to control multiple discrete inputs on a single module. Figure 5.
Chapter 5 Installing the Linear Positioning Module Connecting the Analog Outputs The analog outputs provide the current (or voltage) by which the module controls the servo valve. By controlling the servo valve, the module controls axis motion. ATTENTION: Applying output to an axis with polarity reversed can cause sudden high-speed motion. For maximum safety, leave the analog outputs disconnected and the axis power off until you perform the axis tuning procedures in Chapter 8. Figure 5.
Chapter 5 Installing the Linear Positioning Module ATTENTION: The polarity of the analog outputs is affected by the setting of the most significant bit of the analog range words in the parameter block. (See Chapter 7.) Incorrect wiring of the analog outputs or an incorrect setting of this most significant bit can cause the axis to accelerate out of position when the loop is closed. Power Supply To connect the analog output supply: 1.
Chapter 5 Installing the Linear Positioning Module Connecting the Discrete Outputs The two discrete outputs for each loop are powered by the discrete output power supply. The characteristics of the discrete outputs are: Low no voltage applied to the output High output supply voltage applied to output Maximum Current 100 mA Voltage Drop 1.
Chapter 5 Installing the Linear Positioning Module Power Supply To connect the discrete output power supply, follow these steps: 1. Connect the (+) side of the discrete output power supply to the O/P SUPPLY terminal (40) on the module. 2. Connect the common of the discrete output power supply to ground at the I/O chassis and to the returns (-) of all output devices. 3. Connect the discrete output power supply chassis to ground. 4. Connect the shield to ground at the I/O chassis end.
Chapter 5 Installing the Linear Positioning Module Figure 5.
Chapter 6 Interpreting Module to PLC Data (READS) This chapter explains how to monitor module operation from a programmable controller by reading and interpreting status block data that the module transfers to the programmable controller’s data tables. PLC Communication Overview You must program the programmable controller to communicate with the Linear Positioning Module through block read and block write instructions.
Chapter 6 Interpreting Module to PLC Data (READS) Word Assignment The assignment of the words within the status block is as follows: Figure 6.
Chapter 6 Interpreting Module to PLC Data (READS) Figure 6.2 Module Configuration Word 15 . 14 0 .. ... .. 0 ... ... .. 13 0 ... ... .. 12 11 . 10 0 0 .. ... .. 0 ... ... .. 09 0 .. .. .. .. 08 07 .. .. .. .. 06 Stop/Start Enhancement: 0 = Disabled 1 = Enabled Binary Position Format: 0 = Double Word 1 = Single Word Transducer Interface: 0 = Enabled 1 = Disabled Analog Outputs: 0 = Enabled 1 = Disabled .. .. .. .. 05 .. .. .. .. 04 03 .. .. .. .. 02 .. .. .. .. 01 .. .. .. ..
Chapter 6 Interpreting Module to PLC Data (READS) Figure 6.3 Status Word 1 15 . 14 .. ... .. ... ... .. 13 ... ... .. 12 11 . 10 .. ... .. ... ... .. 09 .. .. .. .. 08 07 .. .. .. .. 06 .. .. .. .. 05 .. .. .. .. 04 03 .. .. .. .. 02 .. .. .. .. 01 .. .. .. ..
Chapter 6 Interpreting Module to PLC Data (READS) Bit 4 – Auto Mode The auto mode bit turns on when the loop is in auto mode, i.e., when the auto/manual bit in the command block is on and the auto/manual hardware input is true. The auto/manual hardware input is true if the module is receiving a high input at the AUTO/MAN discrete input terminal (13/14) or if the discrete inputs are disabled in the parameter block. Don’t confuse the auto mode bit with the auto/manual bit (bit 9).
Chapter 6 Interpreting Module to PLC Data (READS) Bit 10 – Start The start bit reflects the state of the hardware start input (0 = no start, 1 = start). Bit 11 – Stop The stop bit reflects the state of the hardware stop input (0 = stop, 1 = no stop). Important: The hardware stop is a low-true signal. Bit 12 – Jog Forward The jog forward bit reflects the state of the jog forward hardware input (0 = no jog, 1 = jog).
Chapter 6 Interpreting Module to PLC Data (READS) Status Word 2 (words 3 and 7) Status word 2 gives the active setpoint and provides additional status information. Figure 6.4 Status Word 2 15 . 14 .. .. .. . .. . .. .. . 13 .. . .. .. . 12 11 . 10 .. .. .. . .. . .. .. . 09 .. .. .. .. 08 07 .. .. .. .. 06 .. .. .. .. 05 .. .. .. .. 04 03 0 .. .. .. .. 02 .. .. .. .. 01 .. .. .. ..
Chapter 6 Interpreting Module to PLC Data (READS) Bit 6 – Position Valid The position valid bit is on if the next two status block words (i.e., words 4 and 5 for axis 1 and words 8 and 9 for axis 2) contain a valid axis position. Bit 7 – Diagnostic Valid This bit is on if the next two status block words (i.e., words 4 and 5 for axis 1 and words 8 and 9 for axis 2) for this axis contain diagnostic information.
Chapter 6 Interpreting Module to PLC Data (READS) Bit 13 – Feedback Fault The feedback fault bit turns on when the module detects a fault in the transducer interface circuitry. In this event, the module also activates OUTPUT 2 if configured as the loop fault output.
Chapter 6 Interpreting Module to PLC Data (READS) Diagnostic Information (words 4, 5 and 8, 9) After a reset command or powerup, the module displays diagnostic information so you can detect parameter block errors. (The module doesn’t accept command blocks until after it receives a valid parameter block.) Use the diagnostic words to determine the cause of a block transfer error. The block ID identifies the last block received by the module. It is updated with each block transfer.
Chapter 6 Interpreting Module to PLC Data (READS) Table 6.
Chapter 6 Interpreting Module to PLC Data (READS) Figure 6.6 Position Format 15 . 14 ... . .. . .. .. . .. . 13 .. .. . .. . 12 Sign: 0=+ 1=- 15 . 14 . .. .. .. Sign: 0=+ 1=- 11 . 10 ... . .. . .. .. . .. . 09 .. . .. .. . 08 07 .. . .. .. . 06 .. . .. .. . 05 .. . .. .. . 04 03 .. . .. .. . 02 .. . .. .. . 01 .. . .. .. . 00 Most significant 3 digits Position value, BCD or binary format 799.900 inches or 7999.00 mm max .. .. .. .. 13 .. .. .. .. 12 11 . 10 . .. .. .. .. ..
Chapter 6 Interpreting Module to PLC Data (READS) Figure 6.7 Following Error Format 15 . 14 .. .. . .. . ... . .. . 13 .. .. . .. . 12 Sign: 0=+ 1=- 11 . 10 .. .. . .. . ... . .. . 09 .. . .. .. . 08 07 .. . .. .. . 06 .. . .. .. . 05 .. . .. .. . 04 03 .. . .. .. . 02 .. . .. .. . 01 .. . .. .. . 00 Most significant 3 digits Following error value, BCD or binary format 180.000 inches or 4572.00 mm max 15 . 14 .. .. .. .. . .. .. .. 13 .. .. .. .. 12 11 . 10 .. .. .. .. .
Chapter 6 Interpreting Module to PLC Data (READS) Measured Velocity (words 20 and 21) Measured velocity is the instantaneous speed of the axis measured at the transducer. This velocity is calculated using a moving average over the previous 20, 50 or 100 milliseconds (depending on the velocity commanded for the move). For slow moves, a 100 millisecond averaging interval is used to improve resolution. For fast moves, a 50 or 20 millisecond averaging interval is used to improve responsiveness.
Chapter 6 Interpreting Module to PLC Data (READS) Figure 6.10 Desired Velocity Format 15 . 14 . .. .. .. .. .. .. .. 13 .. .. .. .. 12 11 . 10 . .. .. .. .. .. .. .. 09 .. .. . .. . 08 07 .. .. . .. . 06 .. .. . .. . 05 .. .. . .. . 04 03 .. .. . .. . 02 .. .. . .. . 01 .. .. . .. . 00 Desired velocity, BCD 99.99 ips or 999.9 mmps max Binary 327.67 ips or 3276.
Chapter 6 Interpreting Module to PLC Data (READS) Figure 6.12 Desired Deceleration Format 15 . 14 .. .. .. .. . .. .. .. 13 .. .. .. .. 12 11 . 10 .. .. .. .. . .. .. .. 09 .. .. . .. . 08 07 .. .. . .. . 06 .. .. . .. . 05 .. .. . .. . 04 03 02 .. .. . .. . .. .. . .. . 01 .. .. . .. . 00 Desired deceleration, BCD 999.9 ips/s or 9999 mmps/s max Binary 3276.
Chapter 6 Interpreting Module to PLC Data (READS) Maximum Velocity (words 30, 31 and 32, 33) The maximum velocity words represent the maximum speed that the system is capable of moving in each direction, and not necessarily the maximum velocity of a particular move. The module calculates the theoretical maximum positive and negative velocities by monitoring jogs or setpoint or motion block moves and extrapolating the maximum speeds possible with the servo valve fully open.
Chapter 6 Interpreting Module to PLC Data (READS) the accuracy is degraded if the axis is unstable or if the velocity is extremely low. Velocities at or above 10% of the maximum velocity work best. the maximum velocities calculated by the module will not be accurate if motion is impeded by physical obstructions. the maximum velocity predictions will vary slightly for moves at different velocities due to non-linearities in the hydraulic system.
Chapter 7 Formatting Module Data (WRITES) Data Blocks Used in Write Operations Data blocks that you set up in the PLC data table enable you to control the module from your PLC programs. There are four types of data blocks used in write operations. The three discussed in this chapter are parameter, setpoint and command blocks. The motion block is discussed in Chapter 9. Parameter Block (Required) The parameter block contains loop configuration information.
Chapter 7 Formatting Module Data (WRITES) Figure 7.
Chapter 7 Formatting Module Data (WRITES) Parameter Control Word (word 1) The parameter control word identifies the block as a parameter block and provides configuration information common to both loops. You can also disable the transducer interface, analog outputs, and discrete inputs by setting the appropriate bits. If all three sections are disabled, you can test the programmable controller program without connecting the wiring arm to the module. Unused sections do not have to be powered. Figure 7.
Chapter 7 Formatting Module Data (WRITES) Bit 3 – Binary/BCD Bit 3 determines the format of the data contained in block transfer reads and writes. BCD format provides compatibility with older programmable controllers. Binary format provides compatibility with the PLC-5, which uses integer (16-bit 2’s complement) data. Bit 4 – Discrete Inputs Setting this bit to 1 disables the discrete inputs. The state of the inputs can still be monitored by the status block, but the function of each input is disabled.
Chapter 7 Formatting Module Data (WRITES) Bit 7 – Binary Position Format When bit 7 is set to 1, and binary format is specified in the parameter control word (bit 3 = 0), the module can display position and error values between -32.768 and 32.767 inches (-327.68 and 327.67 mm) in the second word of the position or following error in the status block. This feature allows applications with a stroke of less than 32 inches to monitor position and error with a single integer.
Chapter 7 Formatting Module Data (WRITES) Important: If the maximum analog range is negative, the +ANALOG and –ANALOG outputs behave as if they were physically reversed. ATTENTION: An incorrect sign for the analog range can cause the axis to accelerate out of position when you close the loop. Figure 7.3 Analog Range Word 15 . 14 .. .. .. . .. . .. .. . 13 .. . .. .. . 12 Sign: 0 = + Direct action 1 = - Reverse action 11 . 10 .. .. .. . .. . .. .. . 09 .. .. .. .. 08 07 .. .. .. .. 06 .. ..
Chapter 7 Formatting Module Data (WRITES) Figure 7.4 Analog Calibration Constant Words 15 . 14 . .. .. .. .. .. .. .. 13 .. .. .. .. 12 11 . 10 . .. .. .. .. .. .. .. 09 .. . .. .. . 08 07 .. . .. .. . 06 .. . .. .. . 05 .. . .. .. . 04 03 .. . .. .. . 02 .. . .. .. . 01 .. . .. .. . 00 Analog calibration constant for positive motion, BCD 99.99 ips or 999.9 mmps max Binary 327.67 ips or 3276.7 mmps max 15 . 14 .. .. .. . .. . .. .. . 13 .. . .. .. . 12 11 . 10 .. .. .. . .. . .
Chapter 7 Formatting Module Data (WRITES) Figure 7.5 Transducer Calibration Constant Words 15 . 14 0 . .. ... . 0 .. .. .. .. 13 0 .. .. .. .. 12 11 . 10 0 0 . .. ... . 0 .. .. .. .. 09 0 .. ... .. . 08 07 0 .. ... .. . 06 .. ... .. . 05 .. ... .. . 04 03 .. ... .. . 02 .. ... .. . 01 .. ... .. . 00 Most significant digits Transducer calibration constant, BCD or binary 99.9999 microsec/inch or 9.99999 microsec/mm max 15 . 14 . .. ... . .. .. .. .. 13 .. .. .. .. 12 11 .
Chapter 7 Formatting Module Data (WRITES) Important: If you change the axis polarity, exchange the forward and reverse analog calibration constants. The zero-position offset defines the direction of forward and reverse motion. Calculate the zero-position offset by measuring the distance between the zero-position and the transducer’s head, as shown above. The module accepts a maximum of +799.900 inches (+7999.00 millimeters).
Chapter 7 Formatting Module Data (WRITES) If you program both software travel limits to zero, the module defaults to a negative software travel limit of 0 and a maximum positive software travel limit that is 180.0 inches or 4572 mm for one recirculation. If you select binary format, the software travel limits are represented as 2’s-complement integers. ATTENTION: To guard against equipment damage, we recommend that you set software travel limits to match your axis length. Figure 7.
Chapter 7 Formatting Module Data (WRITES) Example: Default Configuration If the zero-position and software travel limits are 0, all measurements are relative to the transducer head and the positive direction is towards the end of the transducer. If you program both software travel limits to 0, the module defaults to the maximum and minimum that it can measure.
Chapter 7 Formatting Module Data (WRITES) Example: Retracting in the Positive Direction In this example, the polarity of the axis has been reversed. The positive direction is now towards the transducer head as indicated by the sign of the zero position offset. Notice that the software travel limit in the positive direction can have a negative sign. Figure 7.11 Retracting in the Positive Direction Zero position = +5.000 Positive Limit = -5.0 Negative Limit = -20.0 +5 Origin Pos. Limit Neg.
Chapter 7 Formatting Module Data (WRITES) Examples: Zero Position Past the End of the Transducer The next two examples show the origin past the fully extended position. Figure 7.13 Zero Position Past the End of the Transducer Head Zero position = +250.000 Positive Limit = +200.0 Negative Limit = +100.0 Neg. Limit Origin +200 +100 0 Neg. Limit Pos. Limit Origin -200 -100 0 Pos. Limit +250 Zero position = -250.000 Positive Limit = -100.0 Negative Limit = -200.
Chapter 7 Formatting Module Data (WRITES) If you leave the in-position band undefined (at zero), the module automatically defaults to twice the value of the position resolution. For one circulation, this would be 0.004 inches. Figure 7.15 In Position Band Word 15 . 14 .. ... .. .. . .. .. . 13 .. . .. .. . 12 11 . 10 .. ... .. .. . .. .. . 09 .. .. .. .. 08 07 .. .. .. .. 06 .. .. .. .. 05 .. .. .. .. 04 03 This value times two is the in position band, BCD or binary 9.999 inch or 99.
Chapter 7 Formatting Module Data (WRITES) Figure 7.17 PID Band Word 15 . 14 .. .. .. . ... .. .. . 13 ... .. .. . 12 11 . 10 .. .. .. . ... .. .. . 09 .. ... .. . 08 07 .. ... .. . 06 .. ... .. . 05 .. ... .. . 04 03 .. ... .. . 02 .. ... .. . 01 .. ... .. . 00 This value times two is the PID band, BCD or binary 9.999 inch or 99.
Chapter 7 Formatting Module Data (WRITES) Excess Following Error (words 14 and 43) The excess following error is the maximum allowable axis error above the expected following error at the programmed velocity for the current move. The expected following error for a given velocity equals the velocity divided by the proportional gain. When the following error reaches the maximum value permitted, as specified by the excess following error parameter, the module initiates an immediate stop (loop fault).
Chapter 7 Formatting Module Data (WRITES) Figure 7.21 Maximum PID Error Word 15 . 14 . .. .. .. .. .. .. .. 13 .. .. .. .. 12 11 . 10 . .. .. .. .. .. .. .. 09 .. .. . .. . 08 07 .. .. . .. . 06 .. .. . .. . 05 .. .. . .. . 04 03 .. .. . .. . 02 .. .. . .. . 01 .. .. . .. . Maximum PID error, BCD or binary 9.999 inch or 99.99 mm max If non zero it must not be within the PID band. 00 50005 The maximum value of this word is 9.999 inches or 99.99 mm.
Chapter 7 Formatting Module Data (WRITES) Proportional Gain (words 17 and 46) The module uses the proportional gain factor KP at axis speeds below the gain break speed. Figure 7.23 Proportional Gain Word 15 . 14 .. .. .. . .. . .. .. . 13 .. . .. .. . 12 11 . 10 .. .. .. . .. . .. .. . 09 .. ... .. . 08 07 .. ... .. . 06 .. ... .. . 05 .. ... .. . 04 03 .. ... .. . 02 .. ... .. . 01 .. ... .. . 00 Proportional gain, BCD or binary 0.9999 ips/mil or 0.9999 mmps/mil max (1 mil = 0.
Chapter 7 Formatting Module Data (WRITES) If gain is relatively high, following error will be relatively small, because the system will be more sensitive to changes in following error. If gain is low, following error becomes relatively larger, because the system is not as responsive to changes in following error. Choose a gain value to match the capabilities of your equipment and provide an adequate system response.
Chapter 7 Formatting Module Data (WRITES) Figure 7.26 Gain Break Plot Commanded Axis speed Immediate Stop Maximum Velocity Gain Break speed Desired Gain = Proportional Gain x Gain Factor slope (IPS/mil) = Proportional Gain Gain Break Point Max Following Error Following Error Excess Error (Determined by Excess Following Error Parameter) 50069 Typically, at axis speeds below the gain break velocity, you would use a relatively high gain to allow precise axis positioning.
Chapter 7 Formatting Module Data (WRITES) Figure 7.27 Gain Factor Word 15 . 14 0 . .. ... . 0 .. .. .. .. 13 0 .. .. .. .. 12 0 11 . 10 . .. ... . .. .. .. .. 09 .. ... .. . 08 07 .. ... .. . 06 .. ... .. . 05 .. ... .. . 04 03 .. ... .. . 02 .. ... .. . 01 .. ... .. . 00 Gain factor, BCD or binary 0.00 to 9.99 50070 The gain factor must be less than 10.0. If you set it to zero, the proportional gain won’t be reduced or increased at any axis speed.
Chapter 7 Formatting Module Data (WRITES) The integral term alters response to positioning errors. If the integral gain is relatively high, the system will be more sensitive to positioning errors. However, if the gain is too high, the axis may overshoot and oscillate around programmed endpoints. On the other hand, if the gain is too low, the system will take longer to compensate for positioning errors.
Chapter 7 Formatting Module Data (WRITES) Figure 7.30 Feedforward Gain Word 15 . 14 0 .. ... .. 0 13 ... ... .. 0 12 ... ... .. 0 11 . 10 .. ... .. 09 ... ... .. 08 ... ... .. 07 06 ... ... .. 05 ... ... .. 04 03 ... ... .. 02 ... ... .. 01 ... ... .. 00 ... ... .. Feedforward gain, BCD or binary 0 99.9% 50073 Without feedforwarding axis motion does not begin until the following error is large enough to overcome friction and inertia.
Chapter 7 Formatting Module Data (WRITES) Global Acceleration/Deceleration (words 24, 25 and 53, 54) This parameter specifies the acceleration and deceleration rate the module uses for all jogs and for those setpoint and motion segment moves that do not use local acceleration and deceleration rates. The deceleration value is also used for executing slide stops during manual mode. Figure 7.32 Global Acceleration/Deceleration Words 15 . 14 . .. .. .. .. .. .. .. 13 .. .. .. .. 12 11 . 10 . .. .. .. ..
Chapter 7 Formatting Module Data (WRITES) The velocity smoothing constant determines how quickly the system will change its acceleration and deceleration. The higher the value, the more quickly acceleration and deceleration will change. A higher, faster value produces jerkier motion, while a lower, slower value produces a smoother transition. The following diagrams demonstrate the effect of the velocity smoothing constant. Figure 7.
Chapter 7 Formatting Module Data (WRITES) Figure 7.35 Higher Velocity Smoothing Constant Velocity Time Acceleration Time Deceleration 50020 Jog Rate (Low and High) (words 27, 28 and 56, 57) The jog rate words define the low and high speeds for software and hardware initiated jogs in either direction. By setting the jog rate select bit in the command block, you select high or low jog rate.
Chapter 7 Formatting Module Data (WRITES) Figure 7.36 Jog Rate (Low and High) Words 15 . 14 . .. .. .. 15 . 14 .. .. ... .. .. .. .. ... .. ... 13 13 .. .. .. .. ... .. ... 12 11 . 10 12 Low jog rate, BCD 99.99 ips or 999.9 mmps max Binary 327.67 ips or 3276.7 mmps max (Must be v the high jog rate.) 11 . 10 . 09 . 08 07 . 06 . 05 . 04 03 . .. .. .. .. .. ... .. .. .. .. .. .. ... 09 .. . .. .. . 08 . ... .. . 07 .. . .. .. . . ... .. . 06 .. . .. .. . . ... .. . 05 .. . .. .. .
Chapter 7 Formatting Module Data (WRITES) Figure 7.
Chapter 7 Formatting Module Data (WRITES) Setpoint Block Control Word (word 1) The setpoint block control word identifies the block as a setpoint block, specifies the axis or axes for which the setpoints are intended, and indicates the number of setpoints defined in the block. Figure 7.38 Setpoint Block Control Word 15 . 14 1 .. .. .. . ... .. .. . 0 13 . 12 11 . 10 0 0 .. .. .. . 0 .. .. .. . 0 ... .. .. . 09 . 08 07 . 06 . 05 . 04 03 . 02 . 01 . 00 . ... .. . 0 . ... .. .
Chapter 7 Formatting Module Data (WRITES) Example: If the axis is stationary at +1 inch (from the zero-position offset), an absolute setpoint move with a position value of 2 inches will move the actuator 1 inch to the +2 inch position. An incremental setpoint move with a position value of 2 inches will move the actuator 2 inches to the +3 inch position. Bits 1 through 12 control setpoints 1 to 12 with a one-to-one correspondence. If a bit is set to 1, the corresponding setpoint move is incremental.
Chapter 7 Formatting Module Data (WRITES) Figure 7.40 Setpoint Position Words 15 . 14 ... . .. . .. .. . .. . 13 .. .. . .. . 12 11 . 10 ... . .. . Sign: 0=+ 1=- .. .. . .. . 09 .. . .. .. . 08 07 .. . .. .. . 06 .. . .. .. . 05 .. . .. .. . 04 03 .. . .. .. . 02 .. . .. .. . 01 .. . .. .. . 00 Most significant digits Setpoint position, BCD or binary 799.900 inches or 7999.00 mm max 15 . 14 . .. .. .. .. .. .. .. 13 .. .. .. .. 12 11 . 10 . .. .. .. .. .. .. .. 09 ... ... .
Chapter 7 Formatting Module Data (WRITES) Local Acceleration/Deceleration The local acceleration and deceleration words define the acceleration and deceleration you want for the corresponding setpoint move. You can disable either or both of these parameters by setting them to zero. The module will then use the global parameter. Figure 7.42 Local Acceleration/Deceleration Words 15 . 14 . .. .. .. .. .. .. .. 13 .. .. .. .. 12 11 . 10 . .. .. .. .. .. .. .. 09 .. . .. .. . 08 07 .. . .. .. .
Chapter 7 Formatting Module Data (WRITES) Figure 7.
Chapter 7 Formatting Module Data (WRITES) Bit 0 – Start Bit 0 in the first axis control word is the start bit. The transition of this bit from low to high (0 to 1) signals a software start command. Upon receiving this command, the module begins the setpoint or motion segment move specified in axis control word 2. In manual mode, this transition causes the module to report a programming error in the status block and abort the move. As long as the start bit remains high, (i.e.
Chapter 7 Formatting Module Data (WRITES) Bit 1 – Hardware Start Enable Bit 1 in the first axis control word is the hardware start enable bit. Setting this bit enables the hardware start input. If this bit is reset, the loop ignores hardware start commands. Note that the discrete inputs must also be enabled by the parameter block before the module will recognize hardware start inputs. Hardware start commands aren’t accepted until the loop is in auto mode.
Chapter 7 Formatting Module Data (WRITES) On = high jog rate If this bit changes state during a jog operation, the axis will accelerate or decelerate to the newly commanded rate at the global acceleration/deceleration rate programmed in the parameter block. Bits 5 and 6 – Forward Jog and Reverse Jog Turning on bit 5 causes axis motion in the forward direction. Similarly, turning on bit 6 causes axis motion in the reverse direction. In addition: the jog bits are valid only if the loop is in manual mode.
Chapter 7 Formatting Module Data (WRITES) Bit 8 – Immediate Stop Setting the immediate stop bit causes the module to immediately set the analog output to zero and turn on OUTPUT 2 if it is configured as the loop fault output. To recover from an immediate stop condition, either issue a reset command or turn the I/O chassis power off and then back on.
Chapter 7 Formatting Module Data (WRITES) Bits 12 and 13 – Readout Select Bits 12 and 13 are the readout select bits. The third and fourth status words for an axis provide either current axis position, following error, or diagnostic information. The readout select bits determine which information is displayed in the status block. It is generally set to diagnostics information when using the extended status information.
Chapter 7 Formatting Module Data (WRITES) Bits 7 to 15 – Reserved Bits 7 to 15 are reserved for future use. The programmable controller program must set them to zero. Setpoint 13 Words (words 3 to 7 and 10 to 14) The setpoint 13 words control position, velocity, acceleration, and deceleration for setpoint 13. These words have the same format as those for the other setpoints in the setpoint block.
Chapter 8 Initializing and Tuning the Axes Before you load an application ladder logic program into the programmable controller, you should follow the procedures in this chapter to initialize and tune the movement of each axis. A simple ladder logic program, QB_SETUP, provided on the accompanying disk, is intended to simplify the initial integration process. Note that all specific references to data tables in the following procedures refer to QB_SETUP.
Chapter 8 Initializing and Tuning the Axes Adjusting the Servo Valve Nulls The first step in initializing the module is to adjust the null on each servo valve. To do so, carry out the following steps: 1. Turn off axis power. 2. Disconnect the servo valve from the module. 3. Start the hydraulic pump and check the system pressure.
Chapter 8 Initializing and Tuning the Axes Table 8.
Chapter 8 Initializing and Tuning the Axes Figure 8.1 Parameter Block Data Table Project Name: QB_SETUP - Axis 1 Page Designer: Date: Address Axis No.
Chapter 8 Initializing and Tuning the Axes Figure 8.2 Command Block Data Table Project Name:QB_SETUP - Axis 1 Designer: Date: Axis No.
Chapter 8 Initializing and Tuning the Axes Figure 8.
Chapter 8 Initializing and Tuning the Axes Verifying Analog Output Polarity You should verify the analog output polarity using low speed open-loop jogs as follows: ATTENTION: Incorrect analog output polarity will cause the axis to accelerate out of position when then loop is closed. The analog output polarity is affected by both the wiring on terminals 29/31 and the sign of the analog range in the parameter block. Verifying Transducer Calibration Constants 1. Turn off axis power. 2.
Chapter 8 Initializing and Tuning the Axes Table 8.B Transducer Calibration Number of Transducer Calibration Constant Circulations Microsec/Inch Microsec/mm 1 9.0500 0.35600 2 18.1000 0.71200 3 27.1500 1.06800 4 36.2000 1.42400 5 45.2500 1.78000 6 54.3000 2.13600 7 63.3500 2.49200 8 72.4000 2.84800 2. Enter the transducer calibration constant from the table into the parameter block for the axis. Send the new parameter block to the module. 3.
Chapter 8 Initializing and Tuning the Axes 8. Record the new axis position value from the module. This value is in the status block words 12 and 13 at N44:12 and N44:13 for axis 1. 9. Subtract the initial axis position from the new axis position and record this as the module distance. 10. Divide the module distance by the actual distance and record this as transducer calibration correction factor. 11.
Chapter 8 Initializing and Tuning the Axes Axis Tuning Each axis needs to be tuned to allow for its specific mechanical and electrical characteristics. If you change system variables, such as hydraulic pressure, cylinder size or servo valve characteristics, you may need to re-tune your axis as well. Remember that every time you change parameters in the parameter block, you should reset the axis using bit 9 of the axis control word 1 (N45:131).
Chapter 8 Initializing and Tuning the Axes Example: Maximum Velocity Calculation If you have a cylinder with a 2 inch bore (inside diameter) and a servo valve rated for 10 gallons per minute, the maximum velocity is approximated as follows: Velocity = 4.9 x 10/22 = 12.25 ips 4. Use bits 5 and 6 of axis control word 1 (N45:131) to jog the axis back and forth between the software travel limits until the maximum velocity stabilizes in the status block.
Chapter 8 Initializing and Tuning the Axes 2. Initialize the loop gains as follows: Proportional gain: Integral gain: Derivative gain: Feedforward gain KP = 0.0050 ips/mil KI = 0 KD = 0 KF = 20.0% 3. Initiate a move using setpoint or jog commands. Increase the feedforward gain until the axis begins to overshoot, i.e., to exceed the desired end position. 4. Decrease the feedforward gain by 10%. This reduced value will result in a more stable performance of the axis.
Chapter 8 Initializing and Tuning the Axes 5. Set the integral gain equal to 70% of the proportional gain at which continuous oscillations occurred (see step 3). KI 6. Set the derivative gain equal to 70% of the proportional gain at which continuous oscillations occurred (see step 3). This small derivative gain is recommended to improve axis stability. KD 7. = 0.7 x KP = 0.7 x KP Check the axis stability under all load conditions.
Chapter 9 Advanced Features The advanced features of the Linear Positioning Module enable you to create complex movement profiles, synchronize multiple axes, and perform cam-emulation. They are not required in order to use the module, and should only be used once you fully understand how to initiate and control motion using setpoints. Motion Block You can implement complex movement profiles using the motion segments of the motion block.
Chapter 9 Advanced Features Important: All segments in a motion block, and the programmable I/O word, become valid as soon as they are downloaded to the module. The one exception is a downloaded segment corresponding to the currently active motion segment. In that case, the active segment must complete its profile or meet its trigger conditions before the new segment becomes valid.
Chapter 9 Advanced Features Figure 9.2 illustrates a motion profile consisting of five motion segments. Segments 14 through 17 move the axis in one direction, while segment 18 returns it to its original position and triggers segment 14. The solid line indicates the actual axis movement and the dotted lines show the profile of each motion segment if its motion were not interrupted by the triggering of the subsequent motion segment.
Chapter 9 Advanced Features Motion Block Control Word The motion block control word identifies the block as a motion block, specifies the number of motion segments defined in the block, and indicates whether or not it contains a programmable I/O control word. (See Figure 9.3.) Nineteen motion blocks must be downloaded to the module to configure all 114 motion segments. Figure 9.3 Motion Block Control Word 15 . 14 0 . .. .. .. 0 .. .. .. .. 13 1 .. .. .. .. 12 11 . 10 0 0 . .. .. .. 0 .. .. .. .
Chapter 9 Advanced Features Programmable Input and Output You can configure the general purpose inputs, INPUT 1 and/or INPUT 2 so that, given their state and the trigger conditions in the current segment, another motion segment may be triggered. Also, any motion segment may optionally pulse or latch the programmable outputs, OUTPUT 1 and OUTPUT 2, when the trigger conditions are satisfied.
Chapter 9 Advanced Features low for the specified duration when triggered to pulse When an output changes to a high or low state, it is guaranteed to stay in that state for a minimum of 16 milliseconds in order to be compatible with the discrete inputs. Thus if two successive changes to an output are initiated within 16 milliseconds of each other, the second change will be delayed until the 16 millisecond interval has expired.
Chapter 9 Advanced Features Bit 7 - Normal/Complement OUTPUT 2 If OUTPUT 2 is configured to be programmable, this bit defines whether OUTPUT 2 is normal (active high) or complement (active low). See the description for bit 3 of this word.
Chapter 9 Advanced Features Default I/O Configuration If you do not download the programmable I/O control word, the module defaults both axes to: INPUT 1 INPUT 2 OUTPUT 1 OUTPUT 2 Motion Segments positive edge trigger high level trigger in-position output loop fault output A motion segment consists of a setpoint, trigger conditions, and programmable output options. (See Figure 9.2.) Motion Segment Control Words The motion segment control words (see Figure 9.
Chapter 9 Advanced Features Figure 9.5 Motion Segment Control Words 15 . 14 0 .. .. .. . ... .. .. . 13 ... .. .. . 12 11 . 10 .. .. .. . ... .. .. . 09 .. ... .. . 08 07 0 .. ... .. . 06 .. ... .. . Motion segment ID (14 to 127), binary format 15 . 14 .. .. .. . 0 .. . .. .. . 13 0 .. . .. .. . 12 0 11 . 10 0 .. .. .. . 0 .. . .. .. . 09 0 05 .. ... .. . 04 03 .. ... .. . 02 .. ... .. . 01 .. ... .. .
Chapter 9 Advanced Features Control Word 2: Bits 4 and 5 - Velocity/Position Trigger These bits indicate if one of the velocity, relative position, or absolute position triggers is active. If the velocity trigger is active, you must specify in the trigger velocity/position word, the absolute velocity at which the trigger condition will be satisfied.
Chapter 9 Advanced Features Desired Position, Local Velocity, Local Acceleration and Local Deceleration Words The format of the (MS) desired position, (LS) desired position, local velocity, local acceleration and local deceleration words in the motion block (see Figure 9.1) is the same as the format of the (MS) setpoint position, (LS) setpoint position, local velocity and local deceleration words in the setpoint block.
Chapter 9 Advanced Features Using the Motion Block As mentioned previously, because initiating a single motion segment from the command block can trigger a sequence of motions, you must exercise caution when using the motion block. For safety reasons, a watchdog monitors the state of the programmable controller. If it faults or enters programming mode while a motion segment is executing, the watchdog in the module initiates a slide stop.
Chapter 9 Advanced Features Important: Incremental motion segments and relative position triggers are based on the current axis position at the beginning of the motion segment’s execution. Because of this, if you link a series of incremental motion segments together you will likely see a small build-up of error. It is recommended that an absolute position move be done occasionally to remove this error build-up.
Chapter 10 Sample Application Programs This chapter gives a general explanation of how to program programmable logic controllers and provides the code for, and descriptions of, the two sample application programs contained on the disk that accompanies the Linear Positioning Module. Application Program 1 shows how to implement axis movement for a single axis using a setpoint block containing four setpoints.
Chapter 10 Sample Application Programs Figure 10.
Chapter 10 Sample Application Programs PLC 5 Block Transfer Instructions You should program a PLC-5 processor’s block transfer to use the bidirectional method to avoid problems when troubleshooting the module. However, block transfer writes only need to be enabled when a command block, motion blocks, setpoint blocks or a parameter block must be sent to the module. Important: Processor execution of block transfer instructions is asynchronous to the program scan.
Chapter 10 Sample Application Programs Important: Note that: the program doesn’t issue the start command for each move until after the module reports in-position (through the status block) from the previous move due to the specified deceleration rate of move 3, the axis will not achieve the final rate of 5 in/s Figure 10.
Chapter 10 Sample Application Programs Planning the Data Blocks for Application Program #1 For this example, we assume a PLC-5/15 controller and assign the data blocks shown in Table 10.A. The files used are shown in Table 10.B. Table 10.A Data Blocks for Application Program #1 Starting Address Block Status N44:1 Parameter N45:1 Setpoint N45:61 Command N45:131 Table 10.
Chapter 10 Sample Application Programs Figure 10.4 Data Table Contents for Application Program #1 Parameter Block Project Name: Application Program #1 - Axis 1 Page Designer: Date: Address Axis No.
Chapter 10 Sample Application Programs Figure 10.5 Data Table Contents for Application Program #1 Setpoint Block Project Name:Application Program #1 - Axis 1 Page Designer: Address Date: Axis No.
Chapter 10 Sample Application Programs Figure 10.6 Data Table Contents for Application Program #1 Command Block Project Name:Application Progam #1 - Axis 1 Page Designer: Address Date: Axis No.
Chapter 10 Sample Application Programs Rung 2:1 Rungs 2:1, 2:2, and 2:3 determine which block (parameter, setpoint, or command) will be sent to the module via the next block transfer write (BTW). If the axis 1 ready bit is low, (the module is in powerup or a reset command has just been executed), rung 2:1 moves the source address of the parameter block into the BTW’s control block. This causes the programmable controller to send the parameter block when rung 2:4 is executed.
Chapter 10 Sample Application Programs Figure 10.
Chapter 10 Sample Application Programs Application Program #2 This application program illustrates how to use a module to control the motion of a single axis using motion blocks. (See Chapter 9.) Figure 10.9 shows the movement profile for this program. Five motion segments describe axis movement. Segments 14 through 17 move the axis in one direction, and segment 18 returns it to its original position and triggers the first motion segment (#14).
Chapter 10 Sample Application Programs Important: Note that: due to the specified acceleration and deceleration rate of move #14, the axis will not achieve the final velocity rate of 5 in/s because moves #16 and #17 have discrete input triggers which may be triggered at any time during their movements profiles, the axis may not achieve the final velocity rates of 2 in/s and 3 in/s all motion segments and programmable I/O information could be contained in a single motion block.
Chapter 10 Sample Application Programs Figure 10.10 to Figure 10.14 show the hexadecimal values for the motion and command blocks, and necessary sequencer data for this example. Figure 10.10 Data Table Contents for Application Program #2 Motion Block 1 Project Name: Application Program #2 - Axis 1 Page Designer: Date: Address Axis No.
Chapter 10 Sample Application Programs Figure 10.11 Data Table Contents for Application Program #2 Motion Block 2 Project Name: Application Program #2 - Axis 1 Page Designer: Date: Address Axis No.
Chapter 10 Sample Application Programs Figure 10.13 Data Table Contents for Application Program #2 Command Block Project Name:Application Progam #2 – Axis 1 Page Designer: Address Date: Axis No.
Chapter 10 Sample Application Programs Program Rungs for Application Program #2 Figure 10.15 and Figure 10.16 show the ladder diagram programming for this application on a PLC-5/15 system. The rungs perform the following functions: Rung 2:0 Rung 2:0 reads the module’s status block and, in conjunction with rung 2:5, performs bidirectional block transfers to and from the module. Important: Set the SQO length in rung 2:3 to the number of motion blocks to be loaded, plus 1.
Chapter 10 Sample Application Programs Figure 10.
Chapter 10 Sample Application Programs Figure 10.
Chapter 11 Troubleshooting The module transfers diagnostic information to the programmable controller in the status block. In addition, the module displays fault information for each loop on the status indicators. Unless the module loses backplane power, all fault conditions cause the fault indicator to turn on. Use the module’s indicators and the status block to diagnose and remedy module faults and errors. Fault Indicators There are three indicators on the module front panel. (See Figure 11.1.
Chapter 11 Troubleshooting Module Fault Indicator This red indicator is normally off. It turns on if there is a module fault in one loop or both loops. Faults may be caused by: loss of analog power analog interface fault memory fault discrete input fault transducer interface fault excess following error excess PID error loss of feedback hardware stop input immediate stop command Loop Active Indicators Each of these green indicators is on when the corresponding loop is active.
Chapter 11 Troubleshooting Table 11.A Troubleshooting Indicators Indication Description Probable Cause Fault Loop 1 Loop 2 Normal Condition Module is fully functional. Fault Loop 1 Loop 2 Power Up State A) Powerup complete, awaiting initial parameter block. A) Send parameter block, monitor status block for parameter block errors. B) Module not receiving DC power from the chassis backplane or wiring arm terminals.
Chapter 11 Troubleshooting 4. Connect the -GATE terminal (3/4) to the -INTERR terminal (7/8). 5. Power up the axis and check the status block for feedback faults. If you still experience feedback faults, make sure that your transducer power supply is providing +5 VDC (+5%) through terminals 9 and 10 on the module’s wiring arm. If there aren’t any feedback faults, then the problems originated in the transducer or the cabling.
Chapter 11 Troubleshooting Figure 11.2 Troubleshooting Flowchart START Consult PLC Assembly and Installation Manual OFF Processor RUN Indicator? ON I/O adapter ACTIVE Indicator OFF Consult PLC Installation Manual ? ON Check the module's Indicators. Power up the I/O chassis containing the module. Return the module for repair if the fault indicator remains lit when you restore power.
Chapter 11 Troubleshooting Figure 11.2 Troubleshooting Flowchart (Continued) A Programming Error ? YES Check diagnostic word(s) to determine the cause of the programming error. NO Take appropriate YES corrective action. Faults indicated by 2nd status word(s) ? NO NO READY bit set ? 2. Check parameter block values. YES Perform a manual jog. 5 1. Check for active stop or reset commands. 2. Re check for errors in status block. 3. Ensure that axis integration has been performed correctly.
Chapter 11 Troubleshooting Figure 11.2 Troubleshooting Flowchart (Continued) B Establish auto mode. Execute a move to each setpoint. 1. Check for active stop or reset commands. Moves executed correctly ? YES END NO 2. Re check for errors in status block. 3. Check setpoint's position, velocity, acceleration and deceleration. 4. Ensure that axis initialization and tuning has been performed correctly. Flowchart Notes 1. Refer to the Table 11.A. 2.
Appendix A Glossary of Terms & Abbreviations Absolute Position: A position described by its distance from the zero point of a coordinate axis. Acceleration: The rate at which the speed of axis motion increases. Adapter Module: A module that provides communication between an I/O chassis and the programmable controller. It transmits I/O chassis input data to, and receives output data from, the programmable controller. Amplifier: A signal gain device whose output is a function of its input.
Appendix A Glossary of Terms & Abbreviations Circulations: A digital process that involves re-triggering an interrogation pulse a fixed number of times by the return pulse, to provide more counting time for digital counter circuitry, thus improving resolution from a linear displacement transducer system. The on time of the digital interface electronics pulse duration output is multiplied by a specified factor. Circulation and recirculation are sometimes used interchangeably.
Appendix A Glossary of Terms & Abbreviations Feedback Resolution: The smallest increment of dimension that the feedback device can distinguish and reproduce as an electrical output. Feedback Signal: The measurement signal indicating the value of a directly controlled variable, which is compared to a commanded value to obtain the corrective error signal. Feedforward Control: Converting information on upstream conditions into corrective commands to minimize the effect of disturbances.
Appendix A Glossary of Terms & Abbreviations LS: Least significant (word, byte, or bit). mA: Milliamperes, a unit of measurement for electric current. Memory: A group of circuit elements that can store data. Millisecond (ms): One thousandth of a second. Module: A unit of a larger assembly. Motion Block: A block containing motion segments and, optionally, a programmable I/O configuration word.
Appendix A Glossary of Terms & Abbreviations Reverse Motion: Axis movement in a negative direction along a coordinate axis. rms: Root mean square. Servo Valve: A hydraulic valve assembly capable of controlling the linear movement of a tool or workpiece. Setpoint: A pre-defined position on the axis. Shield: A conductive barrier that reduces the effect of electric and/or magnetic fields. Sign: The symbol or bit that distinguishes positive from negative numbers.
Appendix B Status Block Figure B.
Appendix B Status Block Figure B.2 Module Configuration Word (word 1) 15 . 14 .. ... .. 0 0 13 ... ... .. 0 ... ... .. 12 11 . 10 0 0 .. ... .. 0 09 ... ... .. 08 .. .. .. .. 0 07 .. .. .. .. 06 05 .. .. .. .. 04 03 .. .. .. .. .. .. .. .. 02 .. .. .. .. 01 .. .. .. ..
Appendix B Status Block Figure B.4 Status Word 2 (words 3 and 7) 15 . 14 .. ... .. ... ... .. 13 ... ... .. 12 11 . 10 ... ... .. .. ... .. 09 .. .. .. .. 08 07 .. .. .. .. 06 .. .. .. .. 05 .. .. .. .. 04 03 02 .. .. .. .. 0 .. .. .. .. 01 .. .. .. ..
Appendix B Status Block Figure B.6 Position/Error/Diagnostic Words (words 4, 5; 8, 9; 12, 13; and 14, 15) Position Format 15 . 14 .. .. ... ... .. ... 13 ... .. ... 12 Sign: 0=+ 1=- 15 . 14 . ... .. . 11 . 10 .. .. ... ... .. ... 09 ... ... .. 08 07 ... ... .. 06 ... ... .. 05 ... ... .. 04 03 ... ... .. 02 ... ... .. 01 ... ... .. 00 Most significant 3 digits Position value, BCD or binary format 799.900 inches or 7999.00 mm max .. ... .. . 13 .. ... .. . 12 11 . 10 . ... .. .
Appendix B Status Block Figure B.8 Active Motion Segment/Setpoint (words 10 and 11) 15 . 14 0 .. ... .. ... ... .. 0 13 ... ... .. 0 12 11 . 10 0 0 .. ... .. ... ... .. 0 09 .. .. .. .. 0 08 07 0 0 .. .. .. .. 06 .. .. .. .. 05 .. .. .. .. 04 03 .. .. .. .. 02 .. .. .. .. 01 .. .. .. .. 00 Active motion segment/setpoint, binary format 0 slide stop, 1 to 13 setpoint, 14 to 127 motion segment 50094 Figure B.9 Measured Velocity (words 20 and 21) 15 . 14 . .. .. .. .. .. ..
Appendix B Status Block Figure B.11 Desired Acceleration (words 24 and 25) 15 . 14 .. .. .. .. . .. .. .. 13 .. .. .. .. 12 11 . 10 .. .. .. .. . .. .. .. 09 08 .. .. . .. . 07 .. .. . .. . 06 .. .. . .. . 05 .. .. . .. . 04 03 02 .. .. . .. . .. .. . .. . 01 .. .. . .. . 00 Desired acceleration, BCD 999.9 ips/s or 9999 mmps/s max Binary 3276.7 ips/s or 32767 mmps/s max 50007 Figure B.12 Desired Deceleration (words 26 and 27) 15 . 14 .. ... .. . . ... .. . 13 .. ... .. .
Appendix B Status Block Figure B.14 Maximum Velocity (words 30, 31 and 32, 33) 15 . 14 . .. .. .. .. .. .. .. 13 .. .. .. .. 12 11 . 10 . .. .. .. .. .. .. .. 09 .. . .. .. . 08 07 .. . .. .. . 06 .. . .. .. . 05 .. . .. .. . 04 03 .. . .. .. . 02 .. . .. .. . 01 .. . .. .. . 00 Maximum positive velocity, BCD 99.99 ips or 999.9 mmps max Binary 327.67 ips or 3276.7 mmps max 15 . 14 .. .. .. . .. . .. .. . 13 .. . .. .. . 12 11 . 10 .. .. .. . .. . .. .. . 09 .. .. .. ..
Appendix B Status Block Table B.
Appendix C Parameter Block Figure C.
Appendix C Parameter Block Figure C.2 Parameter Block Control Word (word 1) 15 . 14 0 .. ... .. ... ... .. 1 13 ... ... .. 0 12 11 . 10 0 0 .. ... .. ... ... .. 0 09 .. .. .. .. 0 08 07 .. .. .. .. 06 .. .. .. .. 05 .. .. .. .. 04 03 .. .. .. .. 02 .. .. .. .. Identifies this as a Parameter Block 01 .. .. .. ..
Appendix C Parameter Block Figure C.4 Analog Calibration Constant Words (words 3, 4 and 32, 33) 15 . 14 . .. .. .. .. .. .. .. 13 .. .. .. .. 12 11 . 10 . .. .. .. .. .. .. .. 09 .. . .. .. . 08 07 .. . .. .. . 06 .. . .. .. . 05 .. . .. .. . 04 03 .. . .. .. . 02 .. . .. .. . 01 .. . .. .. . 00 Analog calibration constant for positive motion: BCD 99.99 ips or 999.9 mmps max. Binary 327.67 ips or 3276.7 mmps max. 15 . 14 .. .. .. . .. . .. .. . 13 .. . .. .. . 12 11 . 10 .. .. .
Appendix C Parameter Block Figure C.6 Zero Position Offset Words (words 7, 8 and 36, 37) 15 . 14 ... . .. . .. .. . .. . 13 .. .. . .. . 12 Sign: 0=+ 1=- 11 . 10 ... . .. . .. .. . .. . 09 .. . .. .. . 08 07 .. . .. .. . 06 .. . .. .. . 05 .. . .. .. . 04 03 .. . .. .. . 02 .. . .. .. . 01 .. . .. .. . 00 Most significant digits Zero position offset, BCD or binary 799.900 inches or 7999.00 mm max 15 . 14 . .. .. .. .. .. .. .. 13 .. .. .. .. 12 11 . 10 . .. .. .. .. .. .. ..
Appendix C Parameter Block Figure C.8 In Position Band Word (words 11 and 40) 15 . 14 .. .. .. . 13 ... .. .. . 12 ... .. .. . 11 . 10 .. .. .. . 09 ... .. .. . 08 .. ... .. . 07 06 .. ... .. . 05 .. ... .. . 04 03 .. ... .. . 02 .. ... .. . 01 .. ... .. . 00 .. ... .. . This value times two is the in position band, BCD or binary 9.999 inch or 99.99 mm max 50006 Figure C.9 PID Band Word (words 12 and 41) 15 . 14 .. .. .. . 13 .. . .. .. . 12 .. . .. .. . 11 . 10 .. .. .. .
Appendix C Parameter Block Figure C.12 Maximum PID Error Word (words 15 and 44) 15 . 14 13 .. .. .. .. . .. .. .. 12 .. .. .. .. 11 . 10 09 .. .. .. .. . .. .. .. 08 .. .. . .. . 07 06 .. .. . .. . 05 .. .. . .. . .. .. . .. . 04 03 02 .. .. . .. . 01 .. .. . .. . 00 .. .. . .. . Maximum PID error, BCD or binary 9.999 inch or 99.99 mm max If non zero it must not be within the PID band. 50005 Figure C.13 Integral Term Limit Word (words 16 and 45) 15 . 14 0 . .. .. .. 0 .. .. ..
Appendix C Parameter Block Figure C.15 Gain Break Speed Word (words 18 and 47) 15 . 14 .. .. .. . 13 .. . .. .. . 12 .. . .. .. . 11 . 10 .. .. .. . 09 .. . .. .. . 08 .. ... .. . 07 06 .. ... .. . 05 .. ... .. . 04 03 .. ... .. . 02 .. ... .. . 01 .. ... .. . 00 .. ... .. . Gain break speed, BCD 99.99 ips or 999.9 mmps max Binary 327.67 ips or 3276.7 mmps max 50011 Figure C.16 Gain Factor Word (words 19 and 48) 15 . 14 0 . .. .. .. 0 .. .. .. .. 13 0 .. .. .. .. 12 0 11 .
Appendix C Parameter Block Figure C.18 Derivative Gain Word (words 21 and 50) 15 . 14 ... ... .. .. ... .. 13 ... ... .. 12 11 . 10 ... ... .. .. ... .. 09 .. .. .. .. 08 07 .. .. .. .. 06 .. .. .. .. 05 .. .. .. .. 04 03 02 .. .. .. .. .. .. .. .. 01 .. .. .. .. 00 Derivative gain, BCD or binary 0.9999 max, unitless 50072 Figure C.19 Feedforward Gain Word (words 22 and 51) 15 . 14 0 . ... .. . 0 13 .. ... .. . 0 12 .. ... .. . 0 11 . 10 . ... .. . 09 .. ... .. .
Appendix C Parameter Block Figure C.21 Global Acceleration/Deceleration Words (words 24, 25 and 53, 54) 15 . 14 . .. .. .. .. .. .. .. 13 .. .. .. .. 12 11 . 10 . .. .. .. .. .. .. .. 09 .. . .. .. . 08 07 .. . .. .. . 06 .. . .. .. . 05 .. . .. .. . 04 03 .. . .. .. . 02 .. . .. .. . 01 .. . .. .. . 00 Global acceleration rate BCD 999.9 ips/s or 9999 mmps/s max Binary 3276.7 ips/s or 32767 mmps/s max 15 . 14 .. ... .. ... ... .. 13 ... ... .. 12 11 . 10 .. ... .. ... ... ..
Appendix C Parameter Block Figure C.23 Jog Rate (Low and High) Words (words 27, 28 and 56, 57) 15 . 14 . .. .. .. 15 . 14 .. .. ... .. .. .. .. ... .. ... 13 13 .. .. .. .. ... .. ... 12 11 . 10 12 Low jog rate, BCD 99.99 ips or 999.9 mmps max Binary 327.67 ips or 3276.7 mmps max (Must be v the high jog rate.) 11 . 10 . 09 . 08 07 . 06 . 05 . 04 03 . .. .. .. .. .. ... .. .. .. .. .. .. ... 09 .. . .. .. . . ... .. . 08 07 .. . .. .. . . ... .. . 06 .. . .. .. . . ... .. . 05 ..
Appendix C Parameter Block Table C.A Parameter Block Values Parameter Limits Analog Range 1% to 100% + Analog Calibration Constant 0 to 327.67 ips 0 to 3276.7 mmps - Analog Calibration Constant 0 to 327.67 ips 0 to 3276.7 mmps Transducer Calibration Constant 0.0001 to 99.9999 microsec./in. 0.00001 to 9.99999 microsec./mm Zero Position Offset -799.900 to +799.900 in. -7999.00 to +7999.00 mm + Software Travel Limit -799.9 to +799.9 in. -7999 to +7999 mm - Software Travel Limit -799.
Appendix D Setpoint Block Figure D.1 Setpoint Block Word Assignments Setpoint block control word Incremental/absolute word Up to 62 words (MS) Setpoint position (LS) Setpoint position Local velocity Local acceleration Local deceleration Move #1 (MS) Setpoint position (LS) Setpoint position Local velocity Local acceleration Local deceleration Move #2 : : : (MS) Setpoint position (LS) Setpoint position Local velocity Local acceleration Local deceleration Move #N 50078 Figure D.
Appendix D Setpoint Block Figure D.3 Incremental/Absolute Word (word 2) 15 . 14 0 .. .. .. . 0 13 .. . .. .. . 0 12 .. . .. .. . 11 . 10 .. .. .. . 09 .. . .. .. . 08 .. ... .. . 07 06 .. ... .. . 05 .. ... .. . 04 03 .. ... .. . 02 .. ... .. . 01 .. ... .. . 00 .. ... .. . 0 Setpoints 12 through 1 (0 = absolute, 1 = incremental) 50080 Figure D.4 Setpoint Position Words 15 . 14 .. .. ... ... .. ... 13 ... .. ... 12 11 . 10 .. .. ... Sign: 0=+ 1=- ... .. ... 09 ... .. ..
Appendix D Setpoint Block Figure D.6 Local Acceleration/Deceleration Words 15 . 14 . .. .. .. .. .. .. .. 13 .. .. .. .. 12 11 . 10 . .. .. .. .. .. .. .. 09 .. . .. .. . 08 07 .. . .. .. . 06 .. . .. .. . 05 .. . .. .. . 04 03 .. . .. .. . 02 .. . .. .. . 01 .. . .. .. . 00 Local acceleration rate, BCD 999.9 ips/s or 9999 mmps/s max Binary 3276.7 ips/s or 32767 mmps/s max 15 . 14 .. .. ... ... .. ... 13 ... .. ... 12 11 . 10 .. .. ... ... .. ... 09 .. ... .. . 08 07 .. ..
Appendix E Command Block Figure E.
Appendix E Command Block Figure E.2 Axis Control Word 1 (words 1 and 8) 15 . 14 1 .. ... .. ... ... .. 1 13 ... ... .. 12 11 . 10 0 ... ... .. .. ... .. 09 .. .. .. .. 08 07 .. .. .. .. 06 .. .. .. .. 05 .. .. .. .. 04 03 . 02 .. .. .. .. . .. .. .. 01 .. .. .. ..
Appendix E Command Block Figure E.4 Setpoint 13 Position Words (words 3, 4 and 10, 11) 15 . 14 .. .. ... ... .. ... 13 ... .. ... 12 Sign: 0=+ 1=- 11 . 10 .. .. ... ... .. ... 09 ... ... .. 08 07 ... ... .. 06 ... ... .. 05 ... ... .. 04 03 ... ... .. 02 ... ... .. 01 ... ... .. 00 Most significant digits Setpoint position, BCD or binary 799.900 inches or 7999.00 mm max 15 . 14 . ... .. . .. ... .. . 13 .. ... .. . 12 11 . 10 . ... .. . .. ... .. . 09 .. . .. .. .
Appendix E Command Block Figure E.6 Setpoint 13 Local Acceleration/Deceleration Words (words 6, 7 and 13, 14) 15 . 14 . ... .. . .. ... .. . 13 .. ... .. . 12 11 . 10 . ... .. . .. ... .. . 09 .. . .. .. . 08 07 .. . .. .. . 06 .. . .. .. . 05 .. . .. .. . 04 03 .. . .. .. . 02 .. . .. .. . 01 .. . .. .. . 00 Local acceleration rate BCD 999.9 ips/s or 9999 mmps/s max Binary 3276.7 ips/s or 32767 mmps/s max 15 . 14 ... . .. . .. .. . .. . 13 .. .. . .. . 12 11 . 10 ... . .. . ..
Appendix F Motion Block Figure F.1 Motion Block Word Assignments Motion block control word Motion segment control word 1 Motion segment control word 2 (MS) Desired position (LS) Desired position Local velocity Local acceleration Local deceleration Trigger velocity or (MS) trigger position (LS) Trigger position Up to 56 words . . .
Appendix F Motion Block Figure F.2 Motion Block Control Word 15 . 14 . ... .. . 0 .. ... .. . 0 13 1 .. ... .. . 12 11 . 10 0 0 . ... .. . .. ... .. . 0 09 ... .. .. . 08 07 0 ... .. .. . 06 0 ... .. .. . 05 0 ... .. .. . 04 03 0 Identifies this as a motion block ... .. .. . 02 ... .. ... 01 ... .. ... 00 Number of motion segments specified in this block (0 to 6) Destination: 01 Axis 1 10 Axis 2 11 Both Axes Programmable I/O control word: 0 = No 1 = Yes 50088 Figure F.
Appendix F Motion Block Figure F.4 Motion Segment Control Words 15 . 14 0 .. .. .. . ... .. .. . 13 ... .. .. . 12 11 . 10 .. .. .. . ... .. .. . 09 .. ... .. . 08 07 0 .. ... .. . 06 .. ... .. . Motion segment ID (14 to 127), binary format 15 . 14 .. .. .. . 0 .. . .. .. . 13 0 .. . .. .. . 12 0 11 . 10 0 .. .. .. . 0 .. . .. .. . 09 0 05 .. ... .. . 04 03 .. ... .. . 02 .. ... .. . 01 .. ... .. . 00 Next motion segment ID (14 to 127), slide stop (0), binary format ..
Appendix F Motion Block Figure F.5 Desired/Trigger Position Words 15 . 14 ... . .. . .. .. . .. . 13 .. .. . .. . 12 Sign: 0=+ 1=- 11 . 10 ... . .. . .. .. . .. . 09 .. . .. .. . 08 07 .. . .. .. . 06 .. . .. .. . 05 .. . .. .. . 04 03 .. . .. .. . 02 .. . .. .. . 01 .. . .. .. . 00 Most significant digits Desired/Trigger position, BCD or binary 799.900 inches or 7999.00 mm max 15 . 14 . .. .. .. .. .. .. .. 13 .. .. .. .. 12 11 . 10 . .. .. .. .. .. .. .. 09 ... ... ..
Appendix F Motion Block Figure F.7 Local Acceleration/Deceleration Words 15 . 14 . .. .. .. .. .. .. .. 13 .. .. .. .. 12 11 . 10 . .. .. .. .. .. .. .. 09 .. . .. .. . 08 07 .. . .. .. . 06 .. . .. .. . 05 .. . .. .. . 04 03 .. . .. .. . 02 .. . .. .. . 01 .. . .. .. . 00 Local acceleration rate, BCD 999.9 ips/s or 9999 mmps/s max Binary 3276.7 ips/s or 32767 mmps/s max 15 . 14 .. .. ... ... .. ... 13 ... .. ... 12 11 . 10 .. .. ... ... .. ... 09 .. ... .. . 08 07 .. ...
Appendix G Hexadecimal Data Table Forms For your convenience, we have included data table forms for each type of block, and both axes, where applicable, on the following pages. Copy these forms and fill it in with hexadecimal values for the parameter, setpoint, motion and command blocks, and necessary sequencer data for your PLC programs.
Appendix G Hexadecimal Data Table Forms Project Name: Page Designer: Date: Address Axis No.
Appendix G Hexadecimal Data Table Forms Project Name: Page Designer: Date: Address Axis No.
Appendix G Hexadecimal Data Table Forms Project Name: Page Designer: Date: Address Axis No.
Appendix G Hexadecimal Data Table Forms Project Name: Page Designer: Date: Address Axis No.
Appendix G Hexadecimal Data Table Forms Project Name: Page Designer: Date: Address Axis No.
Appendix G Hexadecimal Data Table Forms Project Name: Page Designer: Date: Address Axis No.
Appendix G Hexadecimal Data Table Forms Project Name: Page Designer: Date: Address Axis No.
Appendix G Hexadecimal Data Table Forms Project Name: Page Designer: Date: Address Axis No.
Appendix G Hexadecimal Data Table Forms Project Name: Page Designer: Date: Address Axis No.
Appendix G Hexadecimal Data Table Forms Project Name: Page Designer: Date: Address Axis No.
Appendix G Hexadecimal Data Table Forms Project Name: Page Designer: Date: Address Axis No.
Appendix H Data Formats Bit 3 in the parameter control word (word 1 in the parameter block) determines the format of the data contained in block transfer reads and writes. BCD format provides compatibility with older programmable controllers. Binary format provides compatibility with the PLC-5, which uses integer (16-bit 2’s complement) data. This appendix explains both these numbering formats.
Appendix H Data Formats Following are two methods to get the negative of a number using the 2’s complement method. Bit Inversion Method To get the 2’s complement of a number using the bit inversion method you must invert each bit from right to left after the first 1. Example: To represent -1524 (decimal) in 16-bit 2’s complement format, we start with the binary equivalent of the positive of the number.
Appendix H Data Formats Example You want to program a global velocity of 1.50 inches/second for axis 1. This value has an implied decimal between the digits 1 and 5. The decimal point is implied because you don’t actually type it when you enter the value into the programmable controller data table. Instead, you enter 150. When the programmable controller writes this value into Word 23 of the module’s parameter block, the module assumes the decimal point and interprets the value correctly as 1.50 ips.
Appendix H Data Formats A sign bit is placed in each word to allow negative binary numbers even with the first word zeroed. Simply signing the first word in this case would not work in binary mode because a word with a value of zero and the sign bit on (i.e., a negative zero) is not equal to zero in the 16-bit 2’s complement system. If the first word of a negative number is zero, turn on the sign bit in the second word.
Appendix I Product Specifications Location • 1771 Universal I/O chassis • One slot Sampling Period • 2 milliseconds for both loops (i.e., both axis positions are read simultaneously every 2 milliseconds) Highest Velocity • 327.67 inches per second • 3276.
Index A Absolute Positioning, 7 29 Acceleration, 7 34 Global, 7 24 Local, 7 32 With Velocity Smoothing, 7 24 Analog Calibration Constants, 7 6 Analog Fault Bit, 6 9 Analog Outputs, 4 7 Interface Terminals, 4 3 Analog Range, 7 5 Auto Mode, 3 4, 7 35 Auto Mode Bit, 6 5 Auto/Manual Bit, 6 5, 7 35 Auto/Manual Input, 4 6 Axis Control Words, 7 32 Axis Motion, Concepts, 7 19 Axis Polarity, 7 9 B Binary/BCD Bit, 7 4 Blended Moves, 9 1 Block Transfer Instructions, 6 1 C Circulations, 2 2 Command Block, 3 2, 9 11
I–2 Index Hardware Stop Input, 4 7 I Immediate Stop Bit, 6 8, 7 37 In Position Band, 7 13 In Position Bit, 6 4 Inch/Metric Bit, 7 3 Incremental Move 13 Bit, 7 35 Incremental Positioning, 7 29, 7 34 Incremental/Absolute Word, 7 29 INPUT 2, Trigger, 9 10 Input Bits, 6 6 Input Triggers, 9 7, 9 10 Inputs Enabled Bit, 6 5 Installation, 5 1 Integral Control, 2 5 Integral Gain, 2 6, 7 21 Integral Limit Reached Bit, 6 8 Integral Term Limit, 7 17 Internal Fault Bit, 6 9 INTPUT 1, Trigger, 9 10 J Jog Bits, 6 6 Jo
Index Ready Bit, 6 3 Reset Bit, 7 37 Reset Control, 2 5 S Interface Terminals, 4 2 Power Supply, 5 11 Transducer Calibration Procedure, 8 7 Trigger Condition, 9 1 Trigger Conditions, 9 3, 9 7 Multiple, 9 10 Setpoint 13 Words, 7 39 Setpoint Block, 3 2 Control Word, 7 28 Setpoint Moves, 3 4 Setpoint Number, 6 7 Setpoint Position, 7 30 Setpoints Received Bit, 6 4 V Velocity Curve Smoothing, 3 3 Velocity Smoothing Constant, 7 24 Velocity, Desired, 2 4 Velocity/Position Trigger, 9 10 Shielded Cables, 5 6 S
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