Analog Input 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. The illustrations, charts, sample programs and layout examples shown in this guide are intended solely for example.
Summary of Changes Summary of Changes Summary of Changes This release of the publication contains updated information from the last release. Updated Information This release includes information previously included in a documentation update (publication 1771-6.5.90–RN1 dated March 1993). In addition, many areas in this publication have been restructured or rewritten.
Table of Contents Summary of Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . S I Using This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P 1 Purpose of Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Audience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Vocabulary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Manual Organization . . . . . . . . . . . . . . . . .
ii Table of Contents Chapter Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 5 Configuring Your Module . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1 Chapter Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Configuring Your Input Module . . . . . . . . . . . . . . . . . . . . . . . . . . Input Range Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Input Type . . . . . . . . . . . . . . . . . . . . . . . .
Table of Contents iii Block Transfer (Mini PLC 2 and PLC 2/20 Processors) . . . D 1 Multiple GET Instructions Mini PLC 2 and PLC 2/20 Processors . Setting the Block Length (Multiple GET Instructions only) . . . . . . . . D 1 D 3 Forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . E 1 Analog Block Transfer Read . . . . . . . . . . . . . . . . . . . . . . . . . . . . Analog Block Transfer Write . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Preface Using This Manual Purpose of Manual This manual shows you how to use your Analog Input module with an Allen-Bradley programmable controller. It helps you install, program, calibrate, and troubleshoot your module. Audience You must be able to program and operate an Allen-Bradley programmable controller to make efficient use of your input module. In particular, you must know how to program block transfers. We assume that you know how to do this in this manual.
Preface Using This Manual Chapter Appendix Related Products Title Topics Covered Title Topics Covered A Specifications B Programming Examples C Data Formats Information on BCD, 2s complement binary, signed magnitude (12 bit) binary D Block transfer with Mini PLC 2 and PLC 2/20 processors How to use GET GET instructions E Forms Useful forms for identifying your data table You can install your input module in any system that uses Allen-Bradley programmable controllers with block transfer c
Preface Using This Manual Do not put the module in the same module group as a discrete high density module. Avoid placing analog input modules close to ac modules or high voltage dc modules. Related Publications For a list of publications with information on Allen-Bradley programmable controller products, consult our publication index (SD499).
Chapter 1 Overview of the Analog Input Module Chapter Objectives This chapter gives you information on: features of the module how the input module communicates with programmable controllers Module Description The Analog input module is an intelligent block transfer module that interfaces analog input signals with any Allen-Bradley programmable controllers that have block transfer capability.
Chapter 1 Overview of the Analog Input Module Table 1.A Program Selectable Input Ranges Voltage Current 1 to 5V dc 4 to 20mA 0 to 5V dc 0 to 20mA 5 to +5V dc 20 to +20mA 10 to +10V dc 0 to 10V dc How Analog Modules Communicate with Programmable Controllers The processor transfers data to the module (block transfer write) and from the module (block transfer read) using BTW and BTR instructions in your ladder diagram program.
Chapter 1 Overview of the Analog Input Module 3. The module converts analog signals into binary or BCD format, and stores theses values until the processor requests their transfer. 4. When instructed by your ladder program, the processor performs a read block transfer of the values and stores them in a data table. 5. The processor and module determine that the transfer was made without error, and that input values are within specified range. 6.
Chapter 2 Installing the Input Module Chapter Objectives This chapter gives you information on: calculating the chassis power requirement choosing the module’s location in the I/O chassis keying a chassis slot for your module wiring the input module’s field wiring arm configuring your module configuration plugs installing the input module Before You Install Your Input Module Electrostatic Damage Before installing your input module in the I/O chassis: You need to: As described under: Calculate the p
Chapter 2 Installing the Input Module Power Requirements Your module receives its power through the 1771 I/O power supply. The module requires 750mA from the backplane. Add this current to the requirements of all other modules in the I/O chassis to prevent overloading the chassis backplane and/or backplane power supply. Module Location in the I/O Chassis Place your module in any I/O module slot of the I/O chassis except for the extreme left slot.
Chapter 2 Installing the Input Module Figure 2.1 Keying Positions Keying Bands 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 1771 IFE Wiring Your Input Module 12676 Connect your I/O devices to the cat. no. 1771-WG wiring arm shipped with the module. Attach the wiring arm to the pivot bar at the bottom of the I/O chassis. It pivots upward and connects with the module so you can install or remove the module without disconnecting the wires.
Chapter 2 Installing the Input Module Figure 2.2 Connection Diagram for 16 Single ended Inputs and Two Wire Transmitters Channel 1 1 Channel 2 2Channel 2 Wire Transmitter 2 3 3 Channel 4 + 1Module – Common Channel 5 Channel 7 – Channel 8 1Module 7 8 Common Channel 9 13 Channel 12 Common Channel 13 2 Channel 15 Jumper all unused channels to module common to reduce noise. 1Module Common 1Module Common The 1771 IFE module does not supply loop power for the input device.
Chapter 2 Installing the Input Module Figure 2.3 Connection Diagram for 16 Single ended Inputs and Four Wire Transmitters Channel 1 1 Channel 2 2Channel – + 4 Wire Transmitter 2 3 3 Channel 4 + 1Module – Common Channel 5 Channel 7 – Channel 8 1Module 7 8 Common Channel 9 13 Channel 12 Common Channel 13 2 Channel 15 Jumper all unused channels to module common to reduce noise. 1Module Common 1Module Common The 1771 IFE module does not supply loop power for the input device.
Chapter 2 Installing the Input Module Figure 2.4 Connection Diagram for 8 Differential Inputs and Two Wire Transmitters Channel 1+ 1 Channel 1 2 Channel 2+ 2 Wire Transmitter + Channel 2 – Not used 3 4 5 Channel 3+ Channel 3 + 6 7 Channel 4+ – 8 Channel 4 9 Not used 10 Channel 5+ 11 Channel 5 Source Ground 12 Channel 6+ 13 Channel 6 14 Not used 15 Channel 7+ 16 NOTE: 1.
Chapter 2 Installing the Input Module Figure 2.5 Connection Diagram for 8 Differential Inputs and Four Wire Transmitters Channel 1+ 1 Channel 1 2 Channel 2+ – + 4 Wire Transmitter + Channel 2 – Not used 3 4 5 Channel 3+ 6 Channel 3 + 7 Channel 4+ – 8 Channel 4 9 Not used 10 Channel 5+ 11 Channel 5 Source Ground 12 Channel 6+ 13 Channel 6 14 Not used NOTE: 1. Unused channels must have their + and inputs jumpered together and tied to module common to reduce noise.
Chapter 2 Installing the Input Module Grounding When using shielded cable wire, ground the foil shield and drain wire only at one end of the cable. We recommend that you wrap the foil shield and drain wire together and connect them to a chassis mounting bolt (Figure 2.6). At the opposite end of the cable, tape exposed shield and drain wire with electrical tape to insulate it from electrical contact. Figure 2.6 Cable Grounding Remove a length of cable jacket from the Belden 8761 cable.
Chapter 2 Installing the Input Module Changing the Module's Configuration The analog input module (1771-IFE) has configuration plugs for determining the input type (voltage or current) desired for each input. The module comes from the factory with the plugs positioned for voltage inputs. To set the configuration plugs for your desired inputs, proceed as follows: 1. Remove the module’s covers by removing the four screws securing the covers to the module. 2. Locate the selection plugs (Figure 2.7).
Chapter 2 Installing the Input Module Figure 2.
Chapter 2 Installing the Input Module Figure 2.9 Configuration Plug Settings for Single ended Voltage and Current Inputs on Adjacent Channels [1] 1 5 9 13 channel 1 (single-ended voltage) channel 2 (single-ended current) channel 3 (single-ended current) channel 4 (single-ended voltage) [1] positions 1 and 2 are not used 10952 I Figure 2.
Chapter 2 Installing the Input Module Module Installation When installing your module in an I/O chassis: 1. First, turn off power to the I/O chassis. ATTENTION: Remove power from the 1771 I/O chassis backplane and wiring arm before removing or installing an I/O module. Failure to remove power from the backplane could cause injury or equipment damage due to possible unexpected operation.
Chapter 3 Module Programming Chapter Objectives In this chapter we describe: block transfer programming sample programs in the PLC-2, PLC-3 and PLC-5 processors module scan time issues Block Transfer Programming Your module communicates with your processor through bidirectional block transfers. This is the sequential operation of both read and write block transfer instructions.
Chapter 3 Module Programming PLC 2 Programming The PLC-2 program example regulates when each block transfer will be initiated to eliminate problems caused by limited regulation of bidirectional block transfers. Both storage bits are needed, as shown in the example, to accomplish this task in all PLC-2 systems, local or remote, with long or short program scans. Therefore, the program as shown is the minimum required.
Chapter 3 Module Programming PLC 3 Programming Block transfer instructions with the PLC-3 processor use one binary file in a data table section for module location and other related data. This is the block transfer control file. The block transfer data file stores data that you want transferred to your module (when programming a block transfer write) or from your module (when programming a block transfer read). The address of the block transfer data files are stored in the block transfer control file.
Chapter 3 Module Programming PLC 5 Programming The PLC-5 program is very similar to the PLC-3 program with the following exceptions: 1. You must use enable bits instead of done bits as the conditions on each rung. 2. A separate control file must be selected for each of the block transfer instructions. Refer to Appendix B. Figure 3.
Chapter 3 Module Programming Module Scan Time Scan time is defined as the amount of time it takes for the input module to read the input channels and place new data into the data buffer. Scan time for your module is shown in Appendix A. The following description references the sequence numbers in Figure 3.4.
Chapter 4 Configuring Your Module Chapter Objectives In this chapter you will read how to configure your module’s features, condition your inputs and enter your data. Configuring Your Input Module Because of the many analog devices available and the wide variety of possible configurations, you must configure your module to conform to the analog device and specific application that you have chosen.
Chapter 4 Module Configuration Input Range Selection You can configure the module to operate with any of five voltage or three current ranges. You can select individual channel ranges using the designated words of the write block transfer instruction (Table 4.A). Use BTW word 1 for range selection of channels 1 through 8, and BTW word 2 for channels 9 through 16. Two bits are allocated for each channel. For example, for channel 1, set word 1 bits 00-01 as shown in Table 4.A. Table 4.
Chapter 4 Module Configuration Input Type You can select single-ended or differential inputs using the designated bit in the configuration file. Inputs to a particular module must be all single-ended or all differential. Set BTW word 3, bit 08 (bit 10 octal) as shown in Table 4.C. Table 4.
Chapter 4 Module Configuration Digital Filtering The module has hardware-based high frequency filters on all channels to reduce the effect of electrical noise on the input signal. Software digital filtering is meant to reduce the effect of process noise on the input signal. Digital filtering is selected using BTW word 3, bits 00-07. The digital filter equation is a classic first order lag equation (Figure 4.1). Using a step input change to illustrate the filter response (Figure 4.
Chapter 4 Module Configuration Real Time Sampling The real time sampling (RTS) mode of operation provides data gathered at precisely timed intervals for use by the processor. BTW word 3 bits 11–15 (13–17 octal) are used to set the real time sampling interval. RTS is invaluable for time based functions (such as PID and totalization) in the PLC. It allows accurate time based calculations in local or remote I/O racks.
Chapter 4 Module Configuration Scaling Your module can perform linear conversion of unscaled data to engineering units, (for example; gallons/minute, degrees C/degrees F and pounds/square inch). Unscaled data in the module has a range of : 0 through 4095 for the polar ranges (0 to 5V DC/0 to 20mA and 1 to 5V DC/4 to 20mA); and -4095 to +4095 (8190) for the bipolar ranges (+5V/+20mA and +10V). BTW words 6 through 37 are the scaling words for channels 1 through 16.
Chapter 4 Module Configuration Important: Scaling values must always be entered in BCD format, even if the data format chosen is binary. If scaling is selected for any channel, all channels must be scaled. If scaling is not required on certain channels, set those to the default input range: 0 to 4095 for 0 to + voltage or current ranges, and -4095 to +4095 for - to + voltage or current ranges. If scaling is not selected, the module requires specific minimum BTR file lengths for the number of channels used.
Chapter 4 Module Configuration Default Configuration If a write block of five words, with all zeroes, is sent to the Analog Input Module (cat. no. 1771-IFE), default selections will be: 1 to 5V DC or 4 to 20mA (dependent on configuration jumper setting) BCD data format no real time sampling (RTS) no filtering no scaling single-ended inputs Figure 4.
Chapter 4 Module Configuration Bit/Word Descriptions for the Analog Input Module Block Transfer Write Configuration Block Note that decimal bits are shown, with octal bits in parentheses. Word Decimal Bit (Octal Bit) Description Word 1 and 2 Bits 00 15 (00 17) Input range selections allow the user to configure the inputs for any of 7 input voltage or current ranges. Two bits are required for each channel. See Table 4.A. Word 3 Bits 00 07 (00 07) Digital filter reduces effect of noise on input.
Chapter 5 Module Status and Input Data Chapter Objectives In this chapter you will read about: reading data from your module block transfer read block format Reading Data From Your Module Block transfer read programming moves status and data from the input module to the processor’s data table in one I/O scan (Figure 5.1). The processor’s user program initiates the request to transfer data from the input module to the processor. Figure 5.
Chapter 5 Module Status and Input Data Block Transfer Read Format The bit/word description for the block transfer read of the Analog Input Module is described below in Table 5.A. Table 5.A BTR Word Format for the Analog Input Module Decimal Bit (Octal Bit) Description Bit 00 Power up bit is used by the module to tell the processor that it is alive but not yet configured. It is a key element in the application program.
Chapter 6 Calibrating Your Module Chapter Objectives In this chapter we tell you what tools you need and how to calibrate your module. Tools and Equipment In order to calibrate your input module you will need the following tools and equipment: Equipment Calibration Procedure Description Digital voltmeter 5 1/2 digit, 0.01% accuracy minimum: Keithley191 or Fluke 8300A or equivalent Alignment tool P/n 35F616, for pot adjustment: Newark Electronics, 500 N.Pulaski Rd.
Chapter 6 Calibrating Your Module Adjusting the 10V Reference 1. Turn off power to your processor and I/O chassis. 2. Swing the field wiring arm out of the way. 3. Remove the module from the I/O chassis. 4. Plug the module into the extender card, and insert the extender card into the I/O chassis. 5. Attach the negative lead to an analog common (pin 5, 10, 15, 20 or 21) of the wiring arm. 6. Attach the positive lead of your voltmeter to TP1. 7.
Chapter 6 Calibrating Your Module Nulling the Input Offset After completing the 10V reference adjustment, turn off power to your processor and I/O chassis and complete the following steps. Chapter Summary 1. Move jumper E1 (Figure 6.1) from the default position (connecting the center and right posts) to the calibration position (connecting the center and left posts). 2. Attach the negative lead of your voltmeter to an analog common (pin 5, 10, 15, 20 or 21) of the field wiring arm. 3.
Chapter 7 Troubleshooting Your Input Module Chapter Objective In this chapter, we describe how to troubleshoot your module by observing the indicators and by monitoring status bits reported to the processor.
Chapter 7 Troubleshooting Your Input Module Word 1 Diagnostics word 1 is the first data word in the read block transfer file for transfer to the central processor. It contains a power-up bit (bit 00) that is set (1) when the module is first powered up. It is reset (0) after a write block transfer. It also contains an under-range or over-range bit (bit 01) that is set when any input is under or over-range.
Chapter 7 Troubleshooting Your Input Module Table 7.A Troubleshooting Chart for Analog Input Module (1771 IFE) Legend Off Indicators Probable Cause RUN (green) FLT (red) On RUN (green) FLT (red) Recommended Action Normal operation None If out of range bit is set (BTR word 1, bit 02) and all 8 under range bits are set (BTR word 2, bits 00 through 07).
Appendix A Specifications Inputs per module 16 single-ended; 8 differential low level Module Location 1771 I/O rack - 1 slot Input voltage ranges (nominal) +1 to +5V dc 0 to 5V dc -5 to +5V dc -10 to +10V dc 0 to +10V dc Input current ranges (nominal) +4 to +20mA 0 to +20mA -20 to +20mA Resolution 12-bit binary 12 bits plus sign on bipolar ranges Accuracy 0.
Appendix B Programming Examples Sample Programs for the Analog Input Module The following are sample programs for entering data in the configuration words of the write block transfer instruction when using the PLC-2, PLC-3 or PLC-5 family processors.
Appendix B Programming Examples Figure B.
Appendix B Programming Examples 1. Press [SHIFT][MODE] to display your ladder diagram on the industrial terminal. 2. Press DD, 03:0[ENTER] to display the block transfer write file. The industrial terminal screen should look like Figure B.2. Notice the highlighted block of zeroes. This highlighted block is the cursor. It should be in the same place as it appears in Figure B.2. If it is not, you can move it to the desired position with the cursor control keys.
Appendix B Programming Examples PLC 5 Family Processors The following is a sample procedure for entering data in the configuration words of the block transfer write instruction when using a PLC-5 processor and 6200 programming software. 1. Enter the following rung: BTW ENABLE BLOCK XFER WRITE RACK : X GROUP : X X MODULE: XX:XX CONTROL: N7:60 DATA FILE: 37 LENGTH: N CONTINUOUS: EN DN ER N7:60 is the address of the BTW transfer file 2.
C Appendix Data Table Formats 4 Digit Binary Coded Decimal (BCD) The 4-digit BCD format uses an arrangement of 16 binary digits to represent a 4-digit decimal number from 0000 to 9999 (Figure C.1). The BCD format is used when the input values are to be displayed for operator viewing. Each group of four binary digits is used to represent a number from 0 to 9. The place values for each group of digits are 20, 21, 22 and 23 (Table C.A).
Appendix C Data Formats Table C.A BCD Representation Signed magnitude Binary 23 (8) Place Value 22 (4) 21 (2) 0 0 0 0 0 0 0 0 1 1 0 0 1 0 2 0 0 1 1 3 0 1 0 0 4 0 1 0 1 5 0 1 1 0 6 0 1 1 1 7 1 0 0 0 8 1 0 0 1 9 20 (1) Decimal Equivalent Signed–magnitude binary is a means of communicating numbers to your processsor. It should be used with the PLC-2 family when performing computations in the processor.
Appendix C Data Formats Two's Complement Binary Two’s complement binary is used with PLC-3 processors when performing mathematical calculations internal to the processor. To complement a number means to change it to a negative number. For example, the following binary number is equal to decimal 22. 101102 = 2210 First, the two’s complement method places an extra bit (sign bit) in the left-most position, and lets this bit determine whether the number is positive or negative.
Appendix D Block Transfer (Mini PLC 2 and PLC 2/20 Processors) Multiple GET Instructions Mini PLC 2 and PLC 2/20 Processors Programming multiple GET instructions is similar to block format instructions programmed for other PLC-2 family processors. The data table maps are identical, and the way information is addressed and stored in processor memory is the same. The only difference is in how you set up block transfer read instructions in your program.
Appendix D Block Transfer (Mini-PLC-2 and PLC-2/20 Processors) Rungs 2 and 3: These output energize instructions (012/01 and 012/02) define the number of words to be transferred. This is accomplished by setting a binary bit pattern in the module’s output image table control byte. The binary bit pattern used (bits 01 and 02 energized) is equivalent to 6 words or channels, and is expressed as 110 in binary notation.
Appendix D Block Transfer (Mini-PLC-2 and PLC-2/20 Processors) Setting the Block Length (Multiple GET Instructions only) The input module transfers a specific number of words in one block length. The number of words transferred is determined by the block length entered in the output image table control byte corresponding to the module’s address. The bits in the output image table control byte (bits 00 - 05) must be programmed to specify a binary value equal to the number of words to be transferred.
Appendix E Forms This appendix contains forms useful in setting up your data table.
Analog Block Transfer Read Position Decimal File Word Octal 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00 17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00 1 Bits not used Diagnostic bits Power Up Bit 2 Data Underrange 3 Data Overrange 4 Data Polarity "0" = (+) "1" = (-) Position 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 E-2 File Word Channel Number Value
Analog Block Transfer Write Position Decimal File Word Octal 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00 17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00 Channels 1 through 8 Range Selection 8 7 6 5 4 Power Up Bit 3 2 1 Channel Number 10 9 Channel Number 1 Channels 9 through 16 Range Selection 16 15 14 13 12 11 2 Position Decimal File Word Octal 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00 17 16 15 14 13 12 11 10 07 06 05
Index B D BCD, 4 1 BCD format, 1 3, 4 7 digital filtering and scaling, 4 1 block transfer, 1 1, 1 3, 2 2, 7 1 communication using, 1 2 read and write file lengths, 4 7 write, 1 2 data format, 4 3 bit selection settings, 4 3 data formats 2's complement binary, C 3 4-digit binary coded decimal, C 1 signed-magnitude binary, C 2 data table usage, P 2 block transfer read, 3 1, 3 2, 5 1, 7 2 bit/word format, 5 2 word assignments, 5 1 default configuration, block transfer write, 3 1, 4 8 block transfer writ
I–2 Index module location, in I/O chassis, 2 2 N noise interference, 2 2, 2 3 P PLC-5, 3 4 scaling description, 4 6 implementation, 4 6 minimum block transfer requirements, 4 7 ranges, 4 6 scan time, module, 3 5 potentiometers, 6 2 selection plugs, locations, 2 9 power requirements, from backplane, 2 2 specifications, A 1 programming, with multiple GETs, D 1 T R range selection bit settings, 4 2 input, 5 2 real time sampling, 4 5 bit settings, 4 5 related products, P 2 related publications, P 3
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