CAS User ’s Guide Watlow Controls 1241 Bundy Blvd. Winona, MN 55987 Customer Service Phone: (800) 414-4299 Fax: (800) 445-8992 Technical Support Phone: (507) 494-5656 Fax: (507) 452-4507 Email: wintechsupport@watlow.com Part No. 21952-60. Revision 1.
Copyright © 1996 Watlow Anafaze Information in this manual is subject to change without notice. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form without written permission from Watlow Anafaze. Warranty Watlow Anafaze, Incorporated warrants that the products furnished under this Agreement will be free from defects in material and workmanship for a period of three years from the date of shipment.
Contents Contents Introduction................................................................1 CAS Features ...................................................................... 3 Specifications...................................................................... 3 Analog Inputs................................................................ 3 Digital Inputs ................................................................ 4 Digital Outputs..............................................................
Contents T/C Inputs ..................................................................... 26 Current Inputs ............................................................... 26 Voltage Inputs............................................................... 27 Unused Inputs ............................................................... 27 Back Terminal Block Connections ............................... 27 Serial Communications....................................................... 28 RS-232 Interface ..........
Contents Display Format ............................................................. 54 High Process Value....................................................... 54 Input Scaling High Reading.......................................... 55 Input Scaling Low Process Value ................................. 55 Input Scaling Low Reading .......................................... 56 Input Filter .................................................................... 56 Setup Channel Alarms ..........................
Contents iv CAS User’s Guide
Overview This manual describes how to install, setup, and operate a CAS. Included are six chapters and a glossary of terms. Each chapter covers a different aspect of your control system and may apply to different users. The following describes the chapters and their purpose. • Introduction: Gives a general description of the CAS and its related specifications. • Installation: Describes how to install the CAS and its peripheral devices.
System Diagram The illustration below shows how the parts of the CAS are connected. When unpacking your system, use the diagram and parts list below to ensure all parts have been shipped. Please don't hesitate to call Watlow Anafaze's Technical Service Department if you have problems with your shipment, or if any CAS components are missing or damaged.
Safety Watlow Anafaze has made efforts to ensure the reliability and safety of the CAS and to recommend safe uses in systems applications. Note that in any application failures can occur. Good engineering practices, electrical codes, and insurance regulations require that you use independent external safety devices to prevent potentially dangerous or unsafe conditions. Assume that the CAS can fail or that other unexpected conditions can occur.
viii CAS User’s Guide
Introduction Introduction The CAS is a modular monitoring system with 16 fully independent inputs. It can function as a stand-alone system; the CAS 1/8 DIN front panel has a Liquid Crystal Display (LCD) and touch keypad for local display and local parameter entry. You can also use it as the key element in a computer supervised data acquisition system; the CAS can be locally or remotely controlled via an RS-232 or RS-485 serial communications interface.
Introduction Front Panel or Computer Operation: Set up and run the CAS from the front panel or from a local or remote computer. Watlow Anafaze offers ANASCAN, our IBM AT or IBM-PC compatible software you can use to operate the CAS. ANASCAN has these features: • • • • Process Overviews Parameter Setup Graphic Trend Plotting Data Logging Multiple Job Storage: Store up to 8 jobs in protected memory, and access them locally by entering a single job number or remotely via digital inputs.
Introduction Specifications This section contains specifications for inputs, serial interface, system power requirements, environmental specifications, and physical dimensions. Analog Inputs Number of Analog Inputs: 16 single-ended/ common ground, plus one pulse input. Input Switching: solid state MUX switching. Input Sampling Rate: 1.5x/second (667 ms) at 60 Hz; 1.25x/second (300 ms) at 50 Hz. Analog Over Voltage Protection: ±20 V referenced to digital ground.
Introduction Voltage inputs: 0-12V, 0-10V, 0-5V, 0-1V, 0-500mV, 0-100 mV with scaling resistors. Range Input Resistance 0-12 V 85K ohms 0-10 V 50 K ohms 0-5 V 40 K ohms 0-1 V 7.4 K ohms 0-500mV 6.2 K ohms 0-100 mV 1.2 K ohms 0-20 mA 3 ohms 0-10 mA 6 ohms Source Impedance: for 0-60 mV, measurements are within specification with up to 500 ohms source resistance. Digital Inputs Number: 8 Configuration: 8 selectable for remote job selection.
Introduction Miscellaneous Specifications Serial Interface Type: RS-232 3 wire or RS-485 4 wire. Isolation: RS-232 None RS-485 To EIA RS-485 Specification. Baud Rate: 2400 or 9600, user selectable. Error Check: BCC or CRC, user selectable. Number of Systems: 1 with RS-232 communications; 32 with RS-485 communications. Protocol: Form of ANSI X3.28-1976. System Power Requirements Voltage: 12-24 Vdc Input Current (no load): 300 mA max Maximum Current Requirement: 610 mA.
Introduction 6 CAS User’s Guide
Installation Installation These installation instructions are written for non-technical users; if you are an electrician or you are technically proficient, they may seem simple to you. This section explains installation for the CAS system only. If you are installing another Watlow Anafaze product, see the manual shipped with it to learn how to install it. This manual uses these symbols: DANGER This symbol warns you about hazards to human life.
Installation Precautions and Warnings DANGER Shut off power to your process before you install the CAS. High voltage may be present even when power is turned off! Reduce the danger of electric shock after installation, mount the CAS in an enclosure that prevents personal contact with electrical components. The CAS measures input signals that are not normally referenced to ground, so the CAS inputs and other signal lines can have high voltage present even when power is turned off.
Installation Recommended Tools Use these tools to install the CAS: Panel Hole Cutters Use any of the following tools to cut a hole of the appropriate size in the panel. • Jigsaw and metal file-for stainless steel and heavyweight panel doors. • Greenlee 1/8 DIN rectangular punch (Greenlee part # 600-68), for most panel materials and thicknesses. • Nibbler and metal file-for aluminum and other lightweight panel doors. Other Tools Use these tools to wire the CAS after you have installed it.
Installation CAS Mounting Procedure NOTE Mount the monitor before you mount the TB-50 or do any wiring. The monitor's placement affects placement and wiring for other components in your system. Mounting Environment Install the CAS in a location free from excessive (>40 ºC) heat, dust, and unauthorized handling. The monitor can mount in any panel material up to 0.2" thick. (Make sure there is enough clearance for mounting brackets and terminal blocks; the monitor extends 6.
Installation TB-50 Mounting Instructions To connect alarms to the CAS System, wire them to the TB-50 (50-pin terminal block). These steps tell you how to mount it on any flat surface. (Please follow this procedure exactly, so you do not damage the terminal block, ribbon cable, or monitor.) 1. Choose a mounting location. Be sure there is enough clearance to install and remove the TB-50; it measures 3.4" long x 3.2" wide x 1.27" tall. 2. Watlow Anafaze shipped the TB-50 to you in an antistatic bag.
Installation 1. Place the TB-50 where you will mount it and use a pencil to trace around the standoffs. 2. Drill and tap #6-32 holes in the locations you marked. 3. Place the TB-50 where you will mount it. Insert the #6 screws in the standoffs and tighten them. NOTE Save the cable tie wraps, ribbon cable, and ribbon cable clamps. You'll use them when you wire outputs to the TB-50 and when you connect the ribbon cable. WARNING Do not connect power to the CAS now.
Installation General Wiring Recommendations Use the cables below or their equivalent. For best results, use appropriate materials, proper installation techniques and the correct equipment. For example, choose wire type by function, installation requirements, and the likelihood of mechanical or electrical problems at your installation. Function No.
Installation Grounding Connect the CAS power supply common to an external ground at only one point, to avoid ground loops that can cause instrument errors or malfunctions. Since the CAS uses a non-isolated measurement system, it has the following connections to power supply common: • Analog Common TB1 pins 5, 6, 11, & 12. • Reference Common, TB1 pin 17. • Communications ground (TB1 pins 23 & 24) if using RS-232. • Power Supply Ground, TB2 pin 2.
Installation Communications Wiring Large systems can pull an extra pair of wires to the computer communications wiring. The extra pair services a sound power phone system for communications between the CAS and a computer. If you choose this option for maintenance, calibration checking, Watlow Anafaze recommends a David Clark #H5030 system.
Installation Wiring: Noise Suppression If the outputs control dry contact electromechanical relays with inductive loads, like alarm horns, you may get Radio-Frequency Interference (RFI, or "noise"). This section explains how to avoid noise problems; read it before you wire the CAS. Symptoms of RFI • If your system displays the following symptoms, suspect RFI. • The CAS display blanks out and then reenergizes as if power had been turned off for a moment. • The process value does not display correctly.
Installation General Wiring This section explains how to test your installation before you connect power to it and how to connect inputs and outputs to it. Power Wiring and System Test When you have installed the system and the TB-50, use this checklist to connect them. (These instructions are written so that non-electricians can understand them. If you are an experienced electrician, they may seem elementary to you. If so, feel free to skim them.) Connecting Power and TB-50 to CAS 1.
Installation WARNING Do not turn on AC power yet. First test the connections, as explained in the Connections Test section (below). Excessive voltage to the CAS will damage it, and you will need to return it to Watlow Anafaze for repair. If you are not using the Watlow Anafaze power supply, read the next section completely and follow its instructions before you apply power. Connections Test 1. Unscrew the four screws on the sides of the front panel. 2.
Installation Outputs NOTE All digital outputs are sink outputs referenced to the 5Vdc supply. These outputs are low (pulled to common) when they are ON. All digital inputs are Transistor-Transistor Logic (TTL) level inputs referenced to control common. The alarm outputs are located on the 50-pin header which connects to the 50-pin flat ribbon cable. This section explains how to wire and configure alarm outputs.
Installation Using the Cable Tie Wraps When you have wired outputs to the TB-50, use the cable tie wraps shipped with it. This diagram shows the cable tie wrap holes. A B 38B 39 40 41 42 43 44 45 46 47 48 49 50 38A 37 36 35 34 33 32 31 30 29 28 27 26 13B 14 15 16 17 18 19 20 21 22 23 24 25 13A 12 11 10 9 8 7 6 5 4 3 2 1 A B B A B Holes labeled "A" are mounting holes. Holes labeled "B" are tie wrap holes.
Installation Alarm Output Connections Typical digital outputs use external optically isolated solid-state relays (SSRs). The SSRs use a 3 to 32 Vdc input for control, and you can size them to switch up to 100 amps at 480 Vac. For larger currents, you can use optically isolated relays to drive contactors. NOTE Digital outputs are SINK outputs. They are Low when the output is On. Connect them to the negative side of Solid State Relays. The figure below shows sample alarm output connections.
Installation TB-50 Connections This table shows TB-50 connections.
Installation Inputs This section covers input scaling and input installation for all input types, including thermocouples, current inputs, and voltage inputs. Input Scaling The analog input circuitry in the CAS accepts any mix of thermocouples, current inputs, and voltage inputs. You can directly connect the following inputs: • J, K, T, S, R, B, PL-II, and N type thermocouples. • Linear inputs with ranges between -10 and 60 mV. Other inputs require custom scaling resistors.
Installation Scaling Values For linear mVdc, Vdc, and mAdc ranges, use 0.1% tolerance resistors. Larger tolerances may cause significant errors. Correct any errors due to resistor tolerance with built-in linear scaling. You can also install other components (like capacitors) for signal conditioning; please consult Watlow Anafaze for more information. The next table shows scaling resistor values. Input Range 24 CAS User’s Guide RC RD All T/C, 0-60 mV DC Jumper 0-10 mA DC 0-20 mA DC Jumper Jumper 6.
Installation The next table shows the location of RC and RD on the analog input board. (The analog input board is the upper board of the two-board set.) Channel # RC RD 1 R58 R42 2 R56 R40 3 R54 R38 4 R52 R36 5 R50 R34 6 R48 R32 7 R46 R30 8 R44 R28 9 R57 R41 10 R55 R39 11 R53 R37 12 R51 R35 13 R49 R33 14 R47 R31 15 R45 R29 16 R43 R27 A wire trace on the printed circuit board jumpers the RC position.
Installation T/C Inputs WARNING Since the CAS has single ended inputs, it has little protectection from common mode voltage sources. Therefore Watlow Anafaze highly recommends that you use ungrounded thermcouples with the EXTERNAL THERMOCOUPLE SHEATH ELECTRICALLY CONNECTED TO EARTH GROUND. You can connect J, K, T, S, R, B, PL-II, and N thermocouples directly to the CAS. Watlow Anafaze provides standard linearization and cold junction compensation for these thermocouple types.
Installation Voltage Inputs • Connect the + side of the voltage input to the In+ terminal. • Connect the - side of the input to analog common. The voltage input range is -10 to 60 mV. • Scale signals larger than 60 mV with scaling resistors that make full scale input 60 mV. (For more information about scaling resistors, request Watlow Anafaze's technical note, Installing Scaling Resistors in the CAS.) The figure below shows a typical voltage input.
Installation Serial Communications The CAS is factory-configured for RS-232 communications. However, the communications are jumper-selectable, so you can switch between RS-232 and RS-485. (See Configuring Communications below.) You can also order a communications cable from Watlow Anafaze or make your own cable. RS-232 Interface With RS-232 communications, you can connect the CAS System directly to the serial communications connector on an IBM-PC or compatible computer.
Installation Wire equipment in a single "daisy chain" using twisted shielded pairs for the RS-485 cables. Don't use "octopus connections" or "spurs". Use a 200 ohm terminating resistor on the RX line of the last system in the system. (If you have only one system, it is the last system in the system.) Use jumper JU1 to select the terminating resistor; place it in B position for termination and A position for non-termination.
Installation Configuring Communications Your system is shipped configured for RS-232. To switch between RS232 and RS-485, change the jumpers as shown here. JU2 JU3 JU4 JU5 A RS-232 B RS-485 Configured for RS-232 B A RS-232 RS-485 Configured for RS-485 You'll need a Phillips head screwdriver and tweezers to switch between RS-232 and RS-485. Follow these steps: 30 CAS User’s Guide 1. Power down the unit. 2. Remove the system's metal casing.
Installation Recommended Wire Gauges Watlow Anafaze recommends the following maximum distances and wire gauges: Distance Wire Gauge Recommended Cable 4000 ft. 24 AWG Belden #9729 Belden #9842 6000 ft. 22 AWG Belden #9184 You may wish to use a shield, depending on your noise environment and grounding problems. The above cables are shielded. NOTE These recommendations are conservative, to ensure that the CAS will operate reliably.
Installation 32 CAS User’s Guide
Using the CAS Using the CAS Introduction This chapter will show you how to use the CAS from the front panel. (If you are using ANASCAN, please see the ANASCAN User's Guide.) The next diagram shows how to reach the operator menus from Single Channel display. (To change global parameters, channel inputs, and alarms from the setup menus, you must enter a special sequence of keys. To learn how, see Setup.
Using the CAS Front Panel The front panel provides a convenient interface with the CAS system. You can program and operate the CAS with the front panel keys shown below, or you can use ANASCAN, a program designed specifically for the CAS. C H AN N E L U N ITS PR O C ES S ALAR M R ESET Alarm Reset -Resetsalarmswhen theprocessissafe ALAR M AC K C H AN N E L N AM E FU N C CHNG SP FUNC -Nofunctioninthe CAS.
Using the CAS Back The Back key works like an "escape" key. Press it to: • Abort editing. • Return to a previous menu. • Switch between single channel and job control displays. Enter Press the Enter key to: • Store data or menu choices after editing and go to the next menu. • Start scanning mode (if pressed twice). Alarm Ack Press Alarm Ack to: • Acknowledge an alarm condition and reset the global alarm.
Using the CAS Single Channel Display Single Channel display (below) shows detailed information for one channel. Process Variable CHANNEL PROCESS Channel Number Default Channel Name Engineering Units UNITS 02 347 °F CHAN 01 CHANNEL NAME ALARM STATUS From Single Channel Display, • Press Yes to go to the next channel. • Press No to go to the previous channel. • Press the Back key once to go to Job display (if it is enabled). • Press Enter twice to start Single Channel Scanning display.
Using the CAS Job Display Job display appears only if: • You have turned on the Remote Job Select function. (This function is explained in Chapter 4: Setup.) • You have selected a job from the job load menu.
Using the CAS Change Setpoint To change the setpoint, go to the Single Channel Display of the channel you want to change, and press the Change Setpoint key (the setpoint is the desired temperature, pH, et cetera, for the process). You should see a display like this: CHANNEL PROCESS UNITS 03 SETPOINT ? 500 ° F CHANNEL NAME ALARM STATUS • Press Yes to change the setpoint. • Then press Yes or No to change the setpoint value.
Using the CAS Alarms If an alarm occurs, an eight character alarm code is displayed in the lower-right section of the display. If a Failed Sensor alarm occurs, the controller also displays this short alarm message: Process Variable Engineering Units CHANNEL PROCESS Channel Number Channel Name UNITS 01 90 °F HTR1 HIGH PRC CHANNEL NAME ALARM STATUS Alarm Message These alarm codes and messages are shown in the table below.
Using the CAS 40 CAS User’s Guide
Setup Setup The Setup menus let you change detailed configuration information. How to Enter the Setup Menus 1. In Single Channel Display, select the channel you wish to edit. 2. While still in Single Channel Display, enter the pass sequence below: Press Enter, Alarm Ack, Change Setpoint. 3. The first setup menu appears.
Setup CAS Menus 42 CAS User’s Guide
Setup Setup Global Parameters Menu The setup global parameters menu looks like this. CHANNEL PROCESS UNITS SETUP GLOBAL PARAMETERS ? CHANNEL NAME ALARM STATUS Load a Job CHANNEL PROCESS UNITS LOAD SETUP FROM JOB ? 1 CHANNEL NAME ALARM STATUS Selectable values: 1 to 8 The following parameters are loaded as part of a job: • Setpoints and spread values • Alarm functions (Off and Alarm), setpoints, high\low process setpoints, high\low deviation setpoints and deadband settings, and channel alarm delay.
Setup Save Setup to Job Use this menu to save job information for every channel, to one of eight jobs in the CAS battery-backed RAM. CHANNEL PROCESS UNITS SAVE SETUP TO JOB ? 1 CHANNEL NAME ALARM STATUS If you have not enabled the remote job control funtion, you will not be able to save a job. If you try it, you will get this message. CHANNEL PROCESS UNITS CANNOT SAVE JOB REMOTE SELECT ON CHANNEL NAME ALARM STATUS Job Select Inputs Use this menu to run up to 8 jobs remotely.
Setup Selectable values: 1, 2, or 3 inputs, or None. These choices have the following effect: Setting Enables 1 input Jobs 1-2 2 inputs Jobs 1-4 3 inputs Jobs 1-8 None (no inputs) Remote Select disabled Job Select Input Polarity This menu lets you set the polarity of the digital inputs used for job selection. You can set the Active state to closed (low) or open (high). CHANNEL PROCESS UNITS JOB SEL DIG INS ACTIVE ? LOW CHANNEL NAME ALARM STATUS Selectable values: High or Low.
Setup Keyboard Lock Status This selection lets you lock the front panel operator function key, Change SP, so that pressing this key has no effect. If you want to use this function, turn off the Keyboard Lock. CHANNEL PROCESS UNITS KEYBOARD LOCK STATUS ? OFF CHANNEL NAME ALARM STATUS Selectable values: On or Off Scanner Address This menu allows you to set the CAS scanner address.
Setup Communications Baud Rate This menu allows you to set the Communications Baud Rate. If using Anascan, ensure that that program has the same baud rate set through the ’scaninst’ program. CHANNEL PROCESS UNITS COMMUNICATIONS BAUD RATE ? 9600 CHANNEL NAME ALARM STATUS Selectable values: 2400 or 9600 Allen-Bradley Protocol This menu is located under the Setup Global Parameters main menu. It allows you to toggle the Allen-Bradley PLC Communications Protocol.
Setup Digital Output Polarity This menu lets you set the polarity of the digital outputs used for alarms. CHANNEL PROCESS UNITS DIG OUT POLARITY ON ALARM ? HIGH CHANNEL NAME ALARM STATUS Selectable values: High or Low External Alarm Acknowledge Input An external alarm reset or acknowledge button can be wired to the CAS at input #8. When activated, it performs the same function as if the "ALARM ACK" key was pressed.
Setup Setup Channel Inputs The Setup Channel Input main menu lets you access menus which change parameters related to the channel input: • Input type • Input units • Input scaling and calibration • Input filtering The next section explains how to use the Input menus to configure your scanner. CHANNEL PROCESS UNITS SETUP CHANNEL 02 INPUT ? CHANNEL NAME ALARM STATUS Input Type This is the first menu of the Setup Channel Inputs menu.
Setup Selectable values: The table shows the input types and ranges. Fahrenheit Range Input Type Celcius Range J -350 to 1400 -212 to 815 K -450 to 2500 -268 to 1371 T -450 to 750 -268 to 399 S 0 to 3200 -18 to 1760 R 0 to 3210 -18 to 1765 B +150 to 3200 +66 to 1760 PL-II +50 to 2012 +10 to 1100 N -450 to 2370 -268 to 1299 Pulse 0-2 KHz (Channel #17 only) Skip Channel is not scanned or displayed Linear See the Linear Scaling section (this chapter) and appendix.
Setup Input Units The Input Units menu lets you choose a three-character description of the channel's engineering units. • Thermocouples can only be ºF or ºC. • If you have selected a linear or pulse input type, you can choose any available character for each character position. For example, you can use GPM or PSI or % for a linear input's units. CHANNEL PROCESS UNITS 02 INPUT UNITS ? °F CHANNEL NAME ALARM STATUS The table below shows the character set for input units.
Setup Linear Scaling Menus The linear scaling menus appear under the Setup Channel Inputs main menu. Linear scaling is available for linear and pulse inputs only. It lets you scale the "raw" input readings (readings in millivolts or hertz) to the engineering units of the process variable. NOTE The linear scaling menus will only be present if you set the channel’s input type to Linear (or, for some menus, to Pulse). For linear inputs, the input reading is in percent (-16.
Setup The PV (Process Variable) range for the scaled input is between the PV values that correspond to the 0% and 100% input readings. For the pulse input, it is between the 0 Hz and 2000 Hz readings. This PV range defines the limits for the setpoint and alarms, as shown here. H iPV Process Variable R ange Lo PV 0 PSI 0% 0mV 0 Hz Lo R dg InputR eading 100% 60 m V Linearinputtype 2000 H z}Pulse inputtype } NOTE For example linear scaling calculations, see Appendix: Linear Scaling.
Setup Display Format This menu lets you select a display format for a linear or pulse input. Choose a format appropriate for your input range and accuracy. (You will only see the Display Format menu if you are editing a linear or pulse input.) CHANNEL PROCESS UNITS 01 DISP FORMAT ? -999 TO 3000 CHANNEL NAME ALARM STATUS The CAS has several available display formats; the display format you choose determines the default values for the rest of the linear scaling menus.
Setup High Reading Use this menu to enter the input level that corresponds to the high process value you entered in the previous menu. (For linear inputs, the high reading is a percentage of the full scale input range. For pulse inputs, the high reading is expressed in Hz.) The 100% full scale input value is 60 mV for the linear input type. CHANNEL PROCESS UNITS 01 INPUT SCALING HI RDG ? 100.0 CHANNEL NAME ALARM STATUS Selectable values: -99.9 to 999.
Setup Low Reading This menu appears under the Setup Channel Inputs main menu. Use it to enter the input level that corresponds to the low process value you selected in the previous menu. For linear inputs, the low reading is a percentage of the full scale input range; for pulse inputs, the low reading is expressed in Hz. The full input range for the linear input type is -10 to CHANNEL PROCESS UNITS 01 INPUT SCALING LO RDG ? 0.0% FS CHANNEL NAME ALARM STATUS 60 mV. For pulse inputs, it is 0 to 2000 Hz.
Setup Setup Channel Alarms The Setup Channel Alarms menu lets you access menus which change alarm function parameters for the current channel. The main alarms menu looks like this: CHANNEL PROCESS UNITS SETUP CHANNEL 01 ALARMS ? CHANNEL NAME ALARM STATUS The CAS has three different kinds of alarms: failed sensor alarms, global alarms, and process alarms. Failed Sensor Alarms Failed sensor alarms alert you to T/C breaks.
Setup • High process and high deviation alarms activate when the process variable goes above a value you set. They remain active until the process variable goes below that value minus the deadband. (See the diagram below.) • Any digital output can be assigned to one or more process variable alarms. The output is active if any of its alarms are active. All alarm outputs are active Low or active High, depending on the global alarm output polarity setting.
Setup Alarm Delay You can set the CAS to delay normal alarm detection and alarm reporting. There are two kinds of alarm delay: • Startup alarm delay delays detection of process alarms (but not failed sensor alarms) for all channels for a time period you set in the Setup Global Parameters main menu. • Channel alarm delay delays failed sensor alarms and process alarms for one channel until the alarm condition is continuously present for longer than the channel alarm delay time you set.
Setup High Process Alarm Output Number This menu lets you choose the digital output that activates when the channel is in high process alarm. You can use this output to activate a second alarm horn or buzzer. CHANNEL PROCESS UNITS 01 HI PROC ALARM OUTPUT ? NONE CHANNEL NAME ALARM STATUS Selectable values: 1 to 34, None NOTE All digital outputs are combined. Therefore you can assign more than one alarm to the same output number, and that output will be On if any of those alarms is On.
Setup High Deviation Alarm Output Number This menu assigns a digital output which activates when the channel is in high deviation alarm. The digital output only activates if you have set the high deviation alarm to On. CHANNEL PROCESS UNITS 01 HI DEV ALARM OUTPUT ? NONE CHANNEL NAME ALARM STATUS Selectable values: 1 to 34, None NOTE All digital outputs are combined. Therefore, you can assign more than one alarm to the same output number, and that output will be On if any of those alarms are On.
Setup Low Deviation Alarm Output Number This menu is used to assign a digital output that activates when the channel is in low deviation alarm. CHANNEL PROCESS UNITS 01 LO DEV ALARM OUTPUT ? NONE CHANNEL NAME ALARM STATUS Selectable values: 1 to 34, None NOTE All digital outputs are OR'd together (combined). Therefore you can assign more than one alarm to the same output number, and that output will be On if any of those alarms is On.
Setup Low Process Alarm Output Number This menu lets you assign the digital output that activates when the channel is in low process alarm. CHANNEL PROCESS UNITS 01 LO PROC ALARM OUTPUT ? NONE CHANNEL NAME ALARM STATUS Selectable values: NONE, 1 to 34 NOTE All digital outputs are combined. Therefore you can assign more than one alarm to the same output number, and that output will be On if any of those alarms is On. Alarm Deadband This menu lets you set an alarm deadband.
Setup Alarm Delay This menu sets a channel alarm delay. There are two types of alarm delay: the startup alarm delay and channel alarm delay. Startup alarm delay (which you can set in the Setup Global Parameters main menu) delays process alarms (but not failed sensor alarms) for all channels for a specified time after the CAS powers up. The channel alarm delay, in contrast, is set separately for each channel.
Setup Manual I/O Test Press Yes at this prompt to see menus which can help you test the digital inputs, digital outputs and the CAS' keypad. CHANNEL PROCESS UNITS MANUAL I/O TEST ? CHANNEL NAME ALARM STATUS Digital Input Testing This is a read-only menu that shows the logic state of the 8 digital inputs as H (High- the input is at 5 volts or is not connected) or L (Low- the input is at zero volts). Inputs 1 to 8 are displayed from left to right.
Setup Digital Output Test This menu lets you manually toggle a digital output On or Off to test it. (Select the output to test in the previous menu.) On may be Low or High depending on the digital output polarity you set. (All outputs are set to Off when you exit this menu.) CHANNEL PROCESS UNITS DIGITAL OUTPUT NUMBER 34: OFF CHANNEL NAME ALARM STATUS Press Yes or No to toggle the output state between On and Off. Keypad Test This menu lets you test the keypad.
Troubleshooting Troubleshooting The next few sections describe general troubleshooting for the CAS. Later sections describe specific procedures, like checking an input, changing the EPROM, and testing the device. First, Check your Installation Please bear in mind that, even in stand-alone systems, the CAS is only part of your system. Often, what appears to be a problem with the CAS is really a problem with other equipment- so check these things first: • Scanner is installed correctly.
Troubleshooting Manual System Reset If the instructions in this manual tell you to perform a "No Key Reset", please do the following: 1. Power down the unit. 2. Press and hold the No key on the front panel. Power up the unit. NOTE A No key reset clears the CAS memory and resets its parameters to their default values. If you have a stand-alone system, there is no way to recover your original parameters.
Troubleshooting Troubleshooting Stand-Alone Systems The CAS is only part of a control system- be sure to check other parts of the system, like thermocouples, before you assume that the unit is broken. To check inputs and outputs, follow these procedures. Checking an Analog Input To check any input except the pulse input, follow these steps: 1. Disconnect the sensor wiring. 2. Set the input sensor to type J T/C from the Setup menus. 3. Place a short across the input.
Troubleshooting Digital Output Test Test digital outputs this way: 1. Connect a 500 ohm to 100 Kohm resistor between the +5V pin (TB-50 screw terminal 1) and the output pin you want to test. 2. Connect the Common lead to the output pin. 3. Connect the voltmeter positive lead to the +5V pin. 4. If you are testing a digital output, use the Manual I/O Test menu to turn the output on and off. (See Chapter 4: Setup for information on the Manual I/O Test menu.
Troubleshooting Checking Computer Supervised Systems Four elements must work properly in a computer supervised system that uses an IBM-compatible computer and ANASCAN: • The CAS. • The computer and its RS-232 or RS-485 serial interface. • The RS-232 or RS-485 communications line. • The computer's software. For CAS troubleshooting, disconnect the communications line from the computer before you follow the troubleshooting steps explained in the previous sections.
Troubleshooting From the setup menus, make sure that the communications parameters (address, error checking and baud rate) are set correctly for each CAS in your system. Every controller must have a separate address, starting with 1 and increasing by 1 for each controller. The error checking method and baud rate must be set the same way in the controller's setup menus and in ANASCAN. Ground Loops On some computers, the RS-232 common wire is tied to earth ground.
Troubleshooting Changing the EPROM Changing the EPROM involves minor mechanical disassembly and reassembly of the CAS, but you don't need any soldering or electrical expertise. The only tools you need are a Phillips head screwdriver and a small flathead screwdriver. NOTE If you change the EPROM, you must perform a No Key Reset for the EPROM change to take effect.
Troubleshooting 5. Find the installed EPROM. This is a 28 pin socketed chip which should have an Watlow Anafaze label on top of it. (If there is no label, a small window will be visible in the middle of the top of the chip.) Do not confuse the EPROM with the RAM; the RAM also has 28 pins, but it is in a high profile socket, and it does not have a label or a window. (The component designation U2 is printed on the processor board next to the EPROM socket.) The next figure shows the EPROM and RAM chip.
Appendix: Linear Scaling Examples Appendix: Linear Scaling Examples Example 1 Situation A pressure sensor that generates a 4-20 milliamp signal is connected to the CAS. The specifications of the sensor state that it generates 4 milliamps at 0.0 PSI and 20 mA at 50.0 PSI. Setup The sensor is connected to a channel input set up with a resistor scaling network to produce 60 millivolts at 20 mA. (See the Inputs section of Chapter 2: Installation for more information on scaling networks.
Appendix: Linear Scaling Examples Example 2 Situation A flow sensor connected to the CAS measures the flow in a pipe. The sensor generates a 0-5V signal. The sensor's output depends on its installation. Independent calibration measurements of the flow in the pipe indicate that the sensor generates 0.5 volts at three gallons per minute (GPM) and 4.75 volts at 65 GPM. The calibration instruments are precise to ±1 gallon per minute.
Appendix: Linear Scaling Examples Example 3 Situation A pulse encoder which measures the movement of a conveyor is connected to the CAS. The encoder generates 900 pulses for every inch the conveyor moves. You want to measure conveyor speed in feet per minute (f/m). Setup The encoder input is connected to the pulse input. An one second sample time gives adequate resolution of the conveyor's speed.
Appendix: Linear Scaling Examples 78 CAS User’s Guide
Glossary A AC See Alternating Current. AC Line Frequency The frequency of the AC power line measured in Hertz (Hz), usually 50 or 60 Hz. Ambient Temperature The temperature of the air or other medium that surrounds the components of a thermal system. American Wire Gauge (AWG) A standard of the dimensional characteristics of wire used to conduct electrical current or signals. AWG is identical to the Brown and Sharpe (B&S) wire gauge.
Glossary Block Check Character (BCC) A serial communications error checking method. An acceptable method for most applications, BCC is the default method. See CRC. Bumpless Transfer A smooth transition from Auto (closed loop) to Manual (open loop) operation. The control output does not change during the transfer. C Calibration The comparison of a measuring device (an unknown) against an equal or better standard. Celsius (Centigrade) Formerly known as Centigrade.
Glossary Deadband The range through which a variation of the input produces no noticeable change in the output. In the deadband, specific conditions can be placed on control output actions. Operators select the deadband. It is usually above the heating proportional band and below the cooling proportional band. Default Parameters The programmed instructions that are permanently stored in the microprocessor software. Derivative Control (D) The last term in the PID algorithm.
Glossary F Fahrenheit The temperature scale that sets the freezing point of water at 32ºF and its boiling point at 212ºF at standard atmospheric pressure. The formula for conversion to Celsius is: ºC=5/9 (ºF-32ºF). Failed Sensor Alarm Warns that an input sensor no longer produces a valid signal. For example, when there are thermocouple breaks, infrared problems or resistance temperature detector (RTD) open or short failures. Filter Filters are used to handle various electrical noise problems.
Glossary I Infrared A region of the electromagnetic spectrum with wavelengths ranging from one to 1,000 microns. These wavelengths are most suited for radiant heating and infrared (noncontact) temperature sensing. Input Process variable information that is supplied to the instrument. Input Scaling The ability to scale input readings (readings in percent of full scale) to the engineering units of the process variable.
Glossary N No Key Reset A method for resetting the controller's memory (for instance, after an EPROM change). Noise Unwanted electrical signals that usually produce signal interference in sensors and sensor circuits. See Electromagnetic Interference. Noise Suppression The use of components to reduce electrical interference that is caused by making or breaking electrical contact, or by inductors. Output Control signal action in response to the difference between setpoint and process variable.
Glossary Proportional Band (PB) A range in which the proportioning function of the control is active. Expressed in units, degrees or percent of span. See PID. Proportional Control A control using only the P (proportional) value of PID control. Pulse Input Digital pulse signals from devices, such as optical encoders. R Ramp A programmed increase in the temperature of a setpoint system. Range The area between two limits in which a quantity or value is measured.
Glossary RS-485—An Electronics Industries of America (EIA) standard for electrical characteristics of generators and receivers for use in balanced digital multipoint systems. This is usually used to communicate with multiple devices over a common cable or where distances over 50 feet are required. Setpoint (SP) The desired value programmed into a controller. For example, the temperature at which a system is to be maintained.
Glossary V Volt (V) The unit of measure for electrical potential, voltage or electromotive force (EMF). See Voltage. Voltage (V) The difference in electrical potential between two points in a circuit. It’s the push or pressure behind current flow through a circuit. One volt (V) is the difference in potential required to move one coulomb of charge between two points in a circuit, consuming one joule of energy.
Glossary 88 CAS User’s Guide
