Block I/O 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. The illustrations, charts, sample programs and layout examples shown in this guide are intended solely for example.
Preface Using This Manual Purpose of Manual This manual shows you how to use your Block I/O with an Allen-Bradley programmable controller. It helps you: install program and troubleshoot your module. Audience You must be able to program and operate an Allen-Bradley programmable controller (PLC) to make efficient use of Block I/O modules. We assume that you know how to do this in this manual.
Preface Using This Manual About Block I/O Block I/O consists of small, self–contained remote I/O devices complete with power supply, programmable controller interface, input/output connections and signal conditioning circuitry. This publication covers the 1791–IOBX and –IOVX block I/O modules. The 1791–IOBX has 64 sinking inputs and 64 sourcing outputs; the 1791–IOVX has 64 sourcing inputs and 64 sinking outputs. In all other aspects, they are identical.
Table of Contents Introducing Block I/O Chapter 1 Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . How the Block I/O Fits in a PLC System . . . . . . . . . . . . . . . . . . Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Installing Block I/O Chapter 2 Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Chapter 1 Introducing Block I/O Chapter Objectives In this chapter you will learn what block I/O is, its features, and how it functions. General Description Block I/O consists of small, self-contained remote I/O devices complete with power supply, programmable controller interface, input/output connections and signal conditioning circuitry. The 1791-IOBX 24V dc module has 64 sink input channels, and 64 source output channels.
Chapter 1 Introducing Block I/O Figure 1.
Chapter 1 Introducing Block I/O Switch Assemblies - Two DIP switches are provided for setting the I/O configuration and rack address. The configuration switch lets you select baud rate, last state, processor restart lockout, last rack and I/O group. The rack address switch lets you select the system rack address for the block. A third switch is provided for selection of the termination resistor. Status Indicators - Indicators are provided for power, active, communication and fuse blown indications.
Chapter 1 Introducing Block I/O In sinking inputs, the dc common is bussed on the block. and the current is sourced from the field device. The sourcing field device switches the hot side of the power supply bus causing current to flow through the sourcing device to the sinking input on the block. Refer to Figure 1.2. Figure 1.2 Sinking Input Example +V Block I/O Bus Field Device Field Device Sinking Input DC Power Supply -V Common 10826-I Sourcing outputs have the power bussed in the block.
Chapter 1 Introducing Block I/O In sourcing input modules (Figure 1.4), the +V on dc circuits is bussed on the module supplying (sourcing) the current for each input circuit. The field device switches the circuit to the common (side of the power supply, sinking the circuit and causing current to flow from the module’s input. Figure 1.4 Sourcing Input Example Block I/O +V DC Power Supply -V Field Device Input dc Common Bus 10917-I In sinking outputs (Figure 1.5), the current flow is reversed.
Chapter 1 Introducing Block I/O Block I/O functions exactly like any Allen-Bradley remote I/O product. Input and output data is scanned asynchronously and transferred back and forth between the block and the controller input and output image table. You connect the block I/O to your remote I/O link as you would any other device. The block looks like a 1/2 I/O rack to the processor, and uses 4 words of input image table memory and 4 words of output image table memory.
Chapter 2 Installing Block I/O Chapter Objectives In this chapter you will learn how to mount the block, how to connect the remote I/O link, how to connect the input and output wiring to the block, and how to terminate the remote I/O link. Pre-installation Considerations Before installation, you must determine: Installing the Block I/O Mounting dimensions for the block I/O module are shown in Figure 2.1. Mount the blocks horizontally with a minimum of 2” between blocks.
Chapter 2 Installing Block I/O Figure 2.1 Mounting Dimensions for the Block I/O Module (Cat. No. 1791-IOBX and -IOVX) 6.15 (156.21) 4.8 (122.0) 0.67 (17.105) 8 7 6 5 4 3 2 1 CONFIGURATION SWITCHES RACK ADDR POWER ACTIVE COMM FUSE Dimensions: 6.15W x 13.0H x 1.72D (156.21W x 334.0H x 43.7D) DISPLAY SELECT INPUT OUTPUT 1791-IOBX 128 POINT 24V DC DISTRIBUTED I/O MODULE 12.7 (322.0) 12.28 (312.0) 13.0 (334.0) CONFIGURATION SWITCHES Inches (Millimeters) GROUP No. GROUP No.
Chapter 2 Installing Block I/O Figure 2.2 Clearance Required for Block I/O Modules 2 (50.8) 2 (50.8) 2 (50.8) 2 (50.8) Connecting Wiring Inches (Millimeters) 10919-I Connections to the block I/O module are made to the removable terminal blocks on each side of the module. Input connections are on the left side, and output connections are on the right side. The input terminal blocks are keyed differently than the output blocks to prevent incorrect insertion.
Chapter 2 Installing Block I/O Table 2.A 1791-IOBX Input Terminal Wiring for Groups 0 and 1 (TRM1) for PLC Family Controllers and SLC Processors SLC Common A Input 00 Input 01 Input 02 Input 03 Input 04 Input 05 Input 06 Input 07 Input 10 Input 11 Input 12 Input 13 Input 14 Input 15 Input 16 Input 17 N.C. Common A Input 00 Input 01 Input 02 Input 03 Input 04 Input 05 Input 06 Input 07 Input 08 Input 09 Input 10 Input 11 Input 12 Input 13 Input 14 Input 15 N.C.
Chapter 2 Installing Block I/O Table 2.B 1791-IOBX Input Terminal Wiring for Groups 2 and 3 (TRM2) for PLC Family Programmable Controllers and SLC Processors Common C Input 00 Input 01 Input 02 Input 03 Input 04 Input 05 Input 06 Input 07 Input 10 Input 11 Input 12 Input 13 Input 14 Input 15 Input 16 Input 17 N.C. SLC Common C Input 00 Input 01 Input 02 Input 03 Input 04 Input 05 Input 06 Input 07 Input 08 Input 09 Input 10 Input 11 Input 12 Input 13 Input 14 Input 15 N.C.
Chapter 2 Installing Block I/O Table 2.C 1791-IOBX Output Terminal Wiring for Groups 0 and 1 (TRM3) for PLC Family Programmable Controllers Terminal N b Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Output Assignment Group 1 PLC SLC N.C. Common B Output 17 Output 16 Output 15 Output 14 Output 13 Output 12 Output 11 Output 10 Output 07 Output 06 Output 05 Output 04 Output 03 Output 02 Output 01 Output 00 VDC B N.C.
Chapter 2 Installing Block I/O Table 2.D 1791-IOBX Output Terminal Wiring for Groups 2 and 3 (TRM4) for PLC Family Programmable Controllers Terminal N b Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Output Assignment Group 3 PLC SLC N.C. Common D Output 17 Output 16 Output 15 Output 14 Output 13 Output 12 Output 11 Output 10 Output 07 Output 06 Output 05 Output 04 Output 03 Output 02 Output 01 Output 00 VDC D N.C.
Chapter 2 Installing Block I/O Table 2.E 1791-IOVX Input Terminal Wiring for Groups 0 and 1 (TRM1) for PLC Family Programmable Controllers PLC VDC A Input 00 Input 01 Input 02 Input 03 Input 04 Input 05 Input 06 Input 07 Input 10 Input 11 Input 12 Input 13 Input 14 Input 15 Input 16 Input 17 N.C. SLC VDC A Input 00 Input 01 Input 02 Input 03 Input 04 Input 05 Input 06 Input 07 Input 08 Input 09 Input 10 Input 11 Input 12 Input 13 Input 14 Input 15 N.C.
Chapter 2 Installing Block I/O Table 2.F 1791-IOVX Input Terminal Wiring for Groups 2 and 3 (TRM2) for PLC Family Programmable Controllers PLC VDC C Input 00 Input 01 Input 02 Input 03 Input 04 Input 05 Input 06 Input 07 Input 10 Input 11 Input 12 Input 13 Input 14 Input 15 Input 16 Input 17 N.C. SLC VDC C Input 00 Input 01 Input 02 Input 03 Input 04 Input 05 Input 06 Input 07 Input 08 Input 09 Input 10 Input 11 Input 12 Input 13 Input 14 Input 15 N.C.
Chapter 2 Installing Block I/O Table 2.G 1791-IOVX Output Terminal Wiring for Groups 0 and 1 (TRM3) for PLC Family Programmable Controllers Terminal N b Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Output Assignment Group 1 PLC SLC N.C. Common B Output 17 Output 16 Output 15 Output 14 Output 13 Output 12 Output 11 Output 10 Output 07 Output 06 Output 05 Output 04 Output 03 Output 02 Output 01 Output 00 VDC B N.C.
Chapter 2 Installing Block I/O Table 2.H 1791-IOVX Output Terminal Wiring for Groups 2 and 3 (TRM4) for PLC Family Programmable Controllers Terminal N b Number 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Output Assignment Group 3 PLC N.C. Common D Output 17 Output 16 Output 15 Output 14 Output 13 Output 12 Output 11 Output 10 Output 07 Output 06 Output 05 Output 04 Output 03 Output 02 Output 01 Output 00 VDC D SLC N.C.
Chapter 2 Installing Block I/O Power Supply Requirements An external 24V dc (+10/-25%) power supply is required to power the block. Total current required to power the block is equal to 300mA. In addition, the external power supply should have current limiting capabilities. The voltage range must not exceed 18.0-26.4V dc. Wiring Requirements Wiring cable requirements are shown in Table 2.J. Table 2.
Chapter 2 Installing Block I/O Remote I/O Link Wiring Blocks must be wired in series as shown in Figure 2.4. Do not attempt to wire any block in parallel. The number of blocks used depends not only on the user requirements but also on the system used. Figure 2.4 Series Connection for Block I/O Using PLC-2, PLC-3 or PLC-5 Family Programmable Controllers To Programmable Controller or I/O Scanner Module 1 I/O Rack 1 I/O Rack 1 I/O Rack 1 I/O Rack Install terminating resistor on last block.
Chapter 2 Installing Block I/O Termination Resistor A termination resistor must be used on the last block in the series. A 150 ohm and 82 ohm termination resistors are built into the unit. To select the termination resistor, position the switch to the desired position as shown in Figure 2.5. Figure 2.
Chapter 2 Installing Block I/O Compatibility of 1771 I/O Products with Extended Node Operation Certain products are not compatible with extended node capabilities obtained with the use of 82 ohm terminators. The following table lists those products that are not compatible.
Chapter 2 Installing Block I/O (This page left intentionally blank.
Chapter 3 Configuring Your Block I/O Chapter Objectives In this chapter you will learn how to configure your block I/O when used with PLC family programmable controllers. This includes the following: setting the configuration switches addressing the block I/O To learn how to configure your block I/O when used with SLC 500 processors, refer to the publication for the 1747-SN Remote I/O Scanner Module.
Chapter 3 Configuring Your Block I/O Figure 3.
Chapter 3 Configuring Your Block I/O Figure 3.2 Configuration Switch Settings (PLC designations shown) Rack Address Switch (Refer to Table 3.A) COM ON 6 5 4 3 2 1 00 01 02 03 04 05 06 07 10 11 12 13 14 15 8 7 6 5 4 3 2 1 +VDC L 00 01 02 03 04 05 06 07 10 11 12 13 14 15 CONFIGURATION SWITCHES RACK ADDR Configuration Switch (Top View of Switch) Not Used set to off 6 5 4 3 2 7 8 I/O Group 6 1 BAUD RATE 1 57.6kbps 115.2kbps 230.
Chapter 3 Configuring Your Block I/O Table 3.
Chapter 3 Configuring Your Block I/O 1747-SN Rack Number 1771-SN Rack Number PLC-2 Rack Number PLC-5 Rack Number PLC-5/250 Rack Number PLC-3 Rack Number 6 5 4 3 2 1 Rack 63 1 1 0 0 1 1 Rack 64 1 1 0 1 0 0 Rack 65 1 1 0 1 0 1 Rack 66 1 1 0 1 1 0 Rack 67 1 1 0 1 1 1 Rack 70 1 1 1 0 0 0 Rack 71 1 1 1 0 0 1 Rack 72 1 1 1 0 1 0 Rack 73 1 1 1 0 1 1 Rack 74 1 1 1 1 0 0 Rack 75 1 1 1 1 0 1 Rack 76 1 1 1 1 1 0 Not Valid
Chapter 3 Configuring Your Block I/O Figure 3.
Chapter 3 Configuring Your Block I/O Table 3.
Chapter 3 Configuring Your Block I/O Table 3.
Chapter 3 Configuring Your Block I/O Table 3.D 1791-IOBX Output Terminal Addressing for Groups 0 and 1 (TRM3) Terminal Number Output Assignment Group 1 Program Address Terminal Number Output Assignment Group 0 1 N.C.
Chapter 3 Configuring Your Block I/O Table 3.E 1791-IOBX Output Terminal Addressing for Groups 2 and 3 (TRM4) Terminal Number Output Assignment Group 3 Program Address Terminal Number Output Assignment Group 2 1 N.C.
Chapter 3 Configuring Your Block I/O Table 3.
Chapter 3 Configuring Your Block I/O Table 3.
Chapter 3 Configuring Your Block I/O Table 3.H 1791-IOVX Output Terminal Addressing for Groups 0 and 1 (TRM3) Program Address N.C.
Chapter 3 Configuring Your Block I/O Table 3.I 1791-IOVX Output Terminal Addressing for Groups 2 and 3 (TRM4) Output Assignment Group 3 Terminal Number 1 Program Address N.C.
Chapter 4 Troubleshooting Chapter Objectives In this chapter you will learn about the indicators on the block I/O module, and how to use them to troubleshoot the unit. Indicators Each block I/O module has indicators (Figure 4.1) which provide indication of specific functions. Each module has the following: Status Indicators - Indicators are provided for power, active, communication and fuse blown indications. An LED array provides input/output status.
Chapter 4 Troubleshooting Figure 4.
Chapter 4 Troubleshooting Table 4.A Troubleshooting Chart Indication P WER POWER (green) COMM (green) ACTIVE (green/red) FUSE (red) Probable Cause Corrective Action Green I/O status on/off Normal indication None required Off No 24V dc power connected, or hardware fault. Check 24V dc power to block Solid green Normal indication - module is communicating with the programmable controller None required Off No communication with adapter, scanner etc. Check that power LED is on.
Chapter 4 Troubleshooting Summary 4-4 4. Replace the blown fuse with a 5.0A slow blow fuse. 5. Reinstall cover and secure with 5 screws removed in step 2. 6. Reapply power to the module. In this chapter you learned what the LED indicators represent, and how to interpret them.
Appendix A Specifications General Specifications External power Range: 18 to 26.4V dc 300mA @ 24V dc; initial surge 2.0A for 10msec Power Dissipation 25.2 Watts (maximum); 15.2 Watts (typical) Thermal Dissipation 86.2 BTU/hr (maximum); 51.9 BTU/hr (typical) Remote I/O Isolation 850V dc (transformer) for 1 second Interconnect cable length PLC or SLC RIO: 57.6K 115.2K 230.
Appendix A Specifications Output Specifications A-2 Number of outputs 64 (4 groups of 16) Output type 1791–IOBX – Source; 1791–IOVX – Sink Maximum output range 18.0 to 26.4V dc @ 300mA resistive Maximum on–state voltage drop 1.5V dc maximum @ 25oC at rated current Maximum on–state current 300mA per point (maximum) Minimum on–state current 5mA (minimum) Output Current per output group 2.4A maximum continuous Surge Current 1.0A for 25ms (maximum), 1 pulse per second max.
Index B baud rate, 3-1, 3-3 inputs, sinking, 1-4 installation, termination resistor, 2-14 C compatibility, 1-1 extended node numbers, 2-15 configuration switches, 3-3 setting, 3-1 connection, in a PLC system, 1-6 connections, wiring, 2-3 L last rack, 3-1, 3-3 LED indicators, 4-1 D description, 1-1 IOBX, 1-3 IOVX, 1-4 dimensions, mounting, 2-1 E extended node capability, 2-14 M mounting, clearance, 2-3 O output, sinking, 1-5 output terminal addressing IOBX groups 0 and 1, 3-9 IOBX groups 2 and 3, 3-10
Index W wiring block designations, 2-11 cable requirements, 2-12 IOBX input terminals 0 and 1, 2-4 2 and 3, 2-5 IOBX output terminals 0 and 1, 2-6 2 and 3, 2-7 IOVX input terminals 0 and 1, 2-8 2 and 3, 2-9 IOVX output terminals 0 and 1, 2-10 2 and 3, 2-11 remote I/O link, 2-12 wiring connections, 2-3 wiring terminals, 1-2 1995 Allen–Bradley Company, Inc. PLC is a registered trademark of Allen–Bradley Company, Inc. PLC–2 is a registered trademark of Allen–Bradley Company, Inc.
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