Rockwell Automation 1771-ILB, D17716.5.91 User Manual

Isolated Analog Input Module Cat. No. 1771-IL Series B

User Manual

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. Since there are many variables and requirements associated with any particular installation, Allen-Bradley does not assume responsibility or liability (to include intellectual property liability) for actual use based upon the examples shown in this publication.

Allen-Bradley publication SGI–1.1, “Safety Guidelines For The Application, Installation and Maintenance of Solid State Control” (available from your local Allen-Bradley office) describes some important differences between solid-state equipment and electromechanical devices which should be taken into consideration when applying products such as those described in this publication.

Reproduction of the contents of this copyrighted publication, in whole or in part, without written permission of Allen–Bradley Company, Inc. is prohibited.

Throughout this manual we make notes to alert you to possible injury to people or damage to equipment under specific circumstances.

ATTENTION: Identifies information about practices or circumstances that can lead to personal injury or death, property damage or economic loss.

Attention helps you:

Identify a hazard. Avoid the hazard. Recognize the consequences.

Important: Identifies information that is especially important for successful application and understanding of the product.

Important: We recommend you frequently backup your application programs on appropriate storage medium to avoid possible data loss.

Summary of Changes

This release of this publication contains new and revised information from the last release.

New Information

This manual covers the series B version of the 1771-IL isolated input module. The 1771-IL series B module has 16-bit resolution, improved sample time, and auto-calibration.

Revised Information

Many areas in this manual have been modified. Change bars (as shown to the right side of this paragraph) are used to indicate new or revised information. Every chapter in this manual has been revised. Please read carefully.

S-1

Using This Manual

Preface

Purpose of Manual

Audience

Vocabulary

Manual Organization

This manual shows you how to use your Isolated Analog Input module with an Allen-Bradley programmable controller. It helps you install, program, calibrate, and troubleshoot your module.

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. If you do not, refer to the appropriate programming and operations manual for your programmable controller before you attempt to program this module.

In this manual, we refer to:

- the 1771-IL series B analog input module as the “input module,” or the “1771-IL/B”

- the Programmable Controller as the “controller”

This manual is divided into seven chapters. The following chart shows each chapter with its corresponding title and a brief overview of the topics covered in that chapter.

Chapter Title Topics Covered

1 Overview of the input module

2 Installing the module

4 Configuring your module

5 Module status and input data Reading data from the module 6 Calibrating your module Information on calibrating your module 7 Troubleshooting Troubleshooting guide for problem diagnosis

Communicating with your module

Description of the module including general and hardware features

Module power requirements, keying, chassis location Wiring of the field wiring arm

Reading data from your module Sample programs

Hardware and software configuration Input range selection Data format

P-1

Preface

Using This Manual

Appendix Title Topics Covered

A Specifications B Configuration Example

Module Descriptions

This chapter gives you information on:

features of the module how the input module communicates with programmable

controllers

The input module is an intelligent block transfer module that interfaces analog input signals with any Allen-Bradley programmable controllers that have block transfer capability. Block transfer programming moves input data words from the module’s memory to a designated area in the processor data table in a single scan. It also moves configuration words from the processor data table to module memory.

The input module is a single-slot module that requires no external power supply. After scanning the analog inputs, the input data is converted to a specified data type in a digital format to be transferred to the processor’s data table on request. The block transfer mode is disabled until this input scan is complete. Consequently, the minimum interval between block transfer reads is the same as the total input update time for each analog input module.

Features

This module senses up to eight analog signals at its inputs and converts them to a proportional four-digit BCD or 16-bit binary value while providing channel to channel and channel to ground isolation of +1000V. You can select from five voltage or three current input ranges. Each input is software selectable on a per channel basis.

This module’s features include:

Eight software configurable differential inputs User program selectable input ranges on a per channel basis (see

Table 1.A) Selectable real-time sampling Selectable scaling to engineering units Selectable digital filtering +1000V input isolation, channel-to-channel, channel-to-ground

Selectable high and low input alarms

1-1

Chapter 1

Overview of the Input Module

able 1.A

Program

Selectable Input Ranges

Voltage Ranges Current Ranges

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, BTW) and from the module (block transfer read, BTR) using BTW and BTR instructions in your ladder diagram program. These instructions let the processor obtain input values and status from the module, and let you establish the module’s mode of operation (Figure 1.1).

1. The processor transfers your configuration data, and alarm values to

the module via a block transfer write instruction.

2. External devices generate analog signals that are transmitted to the

module.

Figure 1.1 Communication

Between Processor and Module

I/O Chassis

Backplane

1-2

Input Module

Cat. No. 1771-IL/B

Programmable Controller

11845-I

Chapter 1

Overview of the Input Module

3. The module converts analog signals into binary or BCD format, and

stores these 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. Your ladder program can use and/or move the data (if valid) before it

is written over by the transfer of new data in a subsequent transfer.

7. Your ladder program should allow write block transfers to the module

only when enabled by operator intervention or at power-up.

Accuracy

Chapter Summary

The accuracy of your input module is described in Appendix A.

In this chapter you read about the functional aspects of the input module and how the module communicates with the programmable controller.

1-3

Chapter

Installing the Input Module

Chapter

Objectives

Before You Install Your Input Module

This chapter gives you information on:

calculating the chassis power requirement choosing the module’s location in the I/O chassis configuring your module voltage/current selection jumpers keying a chassis slot for your module wiring the input module’s field wiring arm installing the input module

Before installing your input module in the I/O chassis you should:

You need to: As described under:

Calculate the power requirements of all modules in each chassis.

Determine where to place the module in the I/O chassis.

Select the input for each channel. Key the backplane connector in the I/O chassis. Module Keying, page 2-4. Make connections to the wiring arm.

Power Requirements, page 2-2.

Module Location in the I/O Chassis, page 2-2. Setting the Voltage/Current Selection Jumpers,

page 2-2.

Wiring Your Input Module, page 2-5, and Grounding, page 2-7

Electrostatic Damage

Electrostatic discharge can damage semiconductor devices inside this module if you touch backplane connector pins. Guard against electrostatic damage by observing the following precautions:

ATTENTION: Electrostatic discharge can degrade performance or cause permanent damage. Handle the module as stated below.

Wear an approved wrist strap grounding device, or touch a grounded

object to rid yourself of electrostatic charge before handling the module.

Handle the module from the front, away from the backplane connector.

Do not touch backplane connector pins.

Keep the module in its static-shield bag when not in use.

2-1

Chapter 2

Installing the Input Module

Power Requirements

Module Location in the I/O Chassis

Your module receives its power through the 1771 I/O power supply. The Isolated Analog input module requires 1.2A at 5V from the power supply.

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.

Place your module in any I/O module slot of the I/O chassis except for the extreme left slot. This slot is reserved for programmable controller processors or adapter modules.

Group your modules to minimize adverse affects from radiated electrical noise and heat. We recommend the following.

Group analog input and low voltage dc modules away from ac modules

or high voltage dc modules to minimize electrical noise interference.

Do not place this module in the same I/O group with a discrete

high-density I/O module when using 2-slot addressing. This module uses a byte in both the input and output image tables for block transfer.

Setting the Voltage/Current Selection Jumpers

After determining the module’s location in the I/O chassis, connect the wiring arm to the pivot bar at the module’s location.

The Isolated Analog Input Module (1771-IL/B) is shipped with each channel set for voltage mode. If a milliamp input is desired, you must set a jumper on the functional analog block (FAB) for that particular channel.

To set the selection jumpers for your desired inputs, proceed as follows:

1. Remove the module’s left hand cover plate (the one without

the labels).

2. Locate the selection plugs (Figure 2.1).

3. Position the jumpers as shown in Figure 2.1 for your

particular module.

4. Reassemble the module after you have finished checking and/or

setting the selection plugs.

2-2

Functional Analog Block

Figure 2.1 Configuration

Chapter 2

Installing the Input Module

Jumper Settings for 1771-IL/B Inputs

Voltage/Current

Jumper

Channel 1

Channel 2

Channel 3

Channel 4

Channel 5

Jumper in

Current position.

Edge View (enlarged)

Jumper in

Voltage position.

Side V

Channel 6

Channel 7

Channel 8

iew

11847-I

2-3

Chapter 2

Installing the Input Module

Installing the Analog Module

locking-bar pins

front of chassis

12453-I

To install 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 disconnect the cable from the module 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.

Failure to remove power from the backplane could cause module damage, degradation of performance, or injury.

2. Lift the locking latch holding the module into the chassis. (On chassis

equipped with a chassis locking bar, pull the locking-bar pins to release the locking bar and swing it up.)

3. Position the keying bands (Figure 2.2) in the backplane connectors to

correspond to the key slots on the module. This prevents you from inserting the wrong module in this slot. This analog module uses:

between 10 and 12 between 32 and 34

ATTENTION: Observe the following precautions when inserting or removing keys:

insert or remove keys with your fingers make sure that key placement is correct

Incorrect keying or the use of a tool can result in damage to the backplane connector and possible system faults.

You can change the position of these bands if subsequent system design and rewiring makes insertion of a different type of module necessary. Use needlenose pliers to insert or remove keying bands.

2-4

Keying Band Location

Between 10 and 12 Between 32 and 34

Figure 2.2 Keying

Positions

I/O chassis

Keying Bands

ATTENTION: Insert or remove

keying bands with your fingers.

Chapter 2

Installing the Input Module

Connecting Wiring to Your Input Module

Upper Connector

11022-I

4. Place the module in the plastic tracks on the top and bottom of the

slot that guides the module into position.

5. Do not force the module into its backplane connector. Apply firm

even pressure on the module until it is firmly seated in the chassis. Note: The chassis locking bar will not close if all modules are not seated properly.

6. Snap the chassis locking bar (or locking latch on earlier chassis) over

the top of the module to secure it. Make sure the locking pins on the locking bar are fully engaged.

7. Connect the wiring to the module as explained under “Connecting

Wiring” below.

Connect your input devices to the cat. no. 1771-WF 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.

Connect inputs to the 1771-IL/B module as shown in Figure 2.3. This module is shipped from the factory configured for voltage inputs but can be configured for any combination of current and voltage inputs. If you want to change the configuration, refer to “Setting the Voltage/Current Selection Jumpers” as explained earlier in this chapter.

Important: The module configuration jumpers must be set for either voltage or current before inserting the module into the I/O chassis.

2-5

Chapter 2

Installing the Input Module

Figure 2.3 Wiring

Connections for the Isolated Analog Input Module (1771-IL/B)

15 14 13

11 10

9 8

7 6

5 4

3 2

Ground

Analog Source

–

Analog Source

–

18 17

16 15

14 13

12 11

6 5

4 3

Channel 1 Channel 2

Channel 3

Channel 4

Channel 5

Channel 6

Channel 7

Channel 8

NOTE: The 1771-IL/B module does not supply loop power for loop

powered analog sources (transmitters, transducers, etc.). Loop power must be supplied by the user.

2-6

Field Wiring Arm Cat. No. 1771-WF

11846-I

Chapter 2

Installing the Input Module

Grounding

Remove a length of cable jacket from the Belden 8761 cable.

Belden

8761 Cable

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 2.4). At the opposite end of the cable, tape exposed shield and drain wire with electrical tape to insulate it from electrical contact.

Figure 2.4 Cable

Grounding

Pull the foil shield and bare drain wire from the insulated wires.

Bare

drain

wire

Insulated wires

Foil shield

Twist the foil shield and drain wire together to form a single strand.

Attach a ground lug.

20104

Chassis Ground Single-point Grounding

When you connect grounding conductors to the I/O chassis grounding stud, place a star washer under the first lug, then place a nut with captive lock washer on top of each ground lug.

Ground Lug

Nut

Grounding Stud

Star Washer

I/O Chassis Side Plate

Use

the cup washer if crimp-on lugs are not used.

Ground Lug

Nut and Captive Washer

19480

19923

#10 Thread-forming screw

External-tooth Washers

Refer to Wiring and Grounding Guidelines, publication 1770-4.1, for additional information.

2-7

Chapter 2

Installing the Input Module

Indicator Lights

The front panel of the input module contains a green RUN and a red FLT (fault) indicator (Figure 2.5). At powerup, an initial module self-check occurs. If there is no fault, the red indicator turns off. The green indicator will blink until the processor completes a successful write block transfer to the module. Upon completion of a block transfer write (BTW), the green RUN indicator will be on and the red FLT indicator will be off. If a fault is found initially or occurs later, the red FLT indicator lights. Possible module fault causes and corrective actions are discussed in Chapter 7, Troubleshooting.

Figure 2.5 Diagnostic

Indicators

ISOLATED

ANALOG INPUT

RUN

FLT

10528-I

Chapter Summary

In this chapter you learned how to install your input module in an existing programmable controller system and how to wire to the field wiring arm.

2-8

Chapter

Communicating With Your Module

Chapter

Objectives

Block Transfer Programming

In this chapter, we describe

block transfer programming quick-start sample programs in the PLC-2, PLC-3 and PLC-5

processors

module scan time issues

Your module communicates with your processor through bidirectional block transfers. This is the sequential operation of both block transfer read (BTR) and block transfer write (BTW) instructions.

A configuration BTW is initiated when the analog module is first powered up, and subsequently only when the programmer wants to enable or disable features of the module. The configuration BTW sets the bits which enable the programmable features of the module, such as scaling, alarming, real time sampling, etc. Block Transfer reads are performed to retrieve information from the module.

Subsequent BTWs occur only when the programmer wants to write a new configuration to the module. At all other times the module is basically in a repetitive block transfer read (BTR) mode.

The following example programs are minimum programs; all rungs and conditioning must be included in your application program. You can disable BTRs, or add interlocks to prevent writes if desired. Do not eliminate any storage bits or interlocks included in the sample programs. If interlocks are removed, the program may not work properly.

The analog input module will work with a default configuration of zeroes entered in the configuration block. This results in the default

settings of: 1 to 5V dc or 4 to 20mA (depending on voltage/current selection jumper), BCD data format, no real time sampling (RTS), no digital filter, no scaling, and no alarms. Refer to Chapter 4 for more information. Also, refer to Appendix B for example configuration blocks and instruction addresses to get started.

Your program should monitor status bits (such as overrange, underrange, alarms, etc.) and block transfer read activity.

The following example programs illustrate the minimum programming required for the 1771-IL series B module to powerup and operate.

3-1

Chapter 3

Communicating With Your Module

PLC-2 Programming

Program

Rung 1

Block transfer read buffer: the file-to-file move instruction holds the block transfer read (BTR) data (file A) until the processor checks the data integrity. If the data was successfully transferred, the processor energizes the BTR done bit, initiating a data transfer to the buffer (file R) for use in the program. If the data is corrupted during the BTR operation, the BTR done bit is not energized and data is not transferred to the buffer file. In this case, the data in the BTR file will be overwritten by data from the next BTR.

Rungs 2 and 3

These rungs provide for a user-initiated block transfer write (BTW) after the module is initialized at power-up. Pressing the pushbutton locks out BTR operation and initiates a BTW that reconfigures the module. Block transfer writes will continue for as long as the pushbutton remains closed.

Rungs 4 and 5

These rungs provide a “read-write-read” sequence to the module at power-up. They also insure that only one block transfer (read or write) is enabled during a particular program scan.

Rungs 6 and 7

These rungs are the conditioning block transfer rungs. Include all the input conditioning shown in the example program.

Action

Block T

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. Note that PLC-2 processors that do not have the block transfer instruction must use the GET-GET block transfer format which is outlined in appendix D.

Figure 3.1 PLC-2

Family Sample Program Structure

ransfer Read

Done Bit

Pushbutton [1]

ransfer W

Done Bit

ransfer W

Done Bit

ransfer Read

Done Bit

Power–up

Bit

Storage

Bit B

Power–up

Bit

Storage

Bit A

rite

Storage

Bit A

BTR Done

Bit

Storage

Bit B

FILE TO FILE MOVE COUNTER POSITION: FILE LENGTH: FILE A: FILE R: RA

TE PER SCAN

Pushbutton [1]

Power-up

Bit

BTR

BLOCK XFER READ DATA ADDR:

MODULE BLOCK LENGTH:

FILE:

BTW

BLOCK XFER WRITE DATA ADDR: MODULE BLOCK LENGTH: FILE:

ADDR:

XXXX – XXXX XXXX – XXXX

RGS

XXXX – XXXX

XXX XXX XXX

XXX

RGS

ENABLE

DONE

Storage

Bit A

Storage

Bit A

Storage

Bit B

Storage

Bit B

ENABLE

DONE

ENABLE

DONE

3-2

[1] You can replace the pushbutton with a timer “done” bit to initiate the block transfer

write on a timed basis. You can also use any storage bit in memory

Chapter 3

Communicating With Your Module

PLC-3 Programming

Program

At power-up, the user program enables a block transfer read. Then it initiates a block transfer write to configure the module.

Action

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.

The industrial terminal prompts you to create a control file when a block transfer instruction is being programmed. The same block transfer

control file is used for both the read and write instructions for your module. A different block transfer control file is required for every

module.

A sample program segment with block transfer instructions is shown in Figure 3.2, and described below.

Figure 3.2 PLC-3

Family Sample Program Structure

Enable

Done

Error

BTR

BLOCK XFER READ Block Transfer Read Done Bit

RACK:

GROUP:

MODULE:

DATA:

LENGTH:

CNTL:

XXX

X = XXXX

XXXX:XXXX XXXX:XXXX

Thereafter, the program continuously performs read and write block transfers.

Block Transfer Write Done Bit

BTW

BLOCK XFER WRITE

RACK:

GROUP:

MODULE:

DATA:

LENGTH:

CNTL:

XXXX:XXXX XXXX:XXXX

X = XXXX

XXX

Enable

Done

Error

3-3

Chapter 3

Communicating With Your Module

PLC-5 Programming

Program

At power-up, the program enables a block transfer read (rung 1). Then it examines the power-up bit in the BTR file and initiates one block transfer write to configure the module (rung 2).

Thereafter, the program continuously reads data from the module (rung 1). A subsequent BTW operation is enabled by a pushbutton switch (rung 2). Changing the processor mode will not initiate a block transfer write.

Action

The PLC-5 program is very similar to the PLC-3 program with the following exceptions:

1. Block transfer enable bits are used instead of done bits as the

conditions on each rung.

2. Separate block transfer control files are used for the block transfer

instructions.

Figure 3.3 PLC-5

Family Sample Program Structure

BTR Enable

Bit

Pushbutton

Power–up Bit

BTW Enable Bit

BTR BLOCK TRANSFER READ

RACK: GROUP: MODULE: CONTROL: DATA FILE:

LENGTH: CONTINUOUS: N

BTW BLOCK TRANSFER WRITE

RACK: GROUP: MODULE: CONTROL: DATA FILE: LENGTH: CONTINUOUS: N

XXX:XX XXX:XX

X X

3-4

Chapter 3

Communicating With Your Module

Module

Scan T

ime

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.

Figure 3.4 Block Transfer T

End of Block

Transfer Write

Block

Transfer

Write

Time

1 2 3 456

ime

Configure

Time

Module available

to perform block transfer

1st

Scan

2nd Scan

3rd Scan

Internal Scan time = 50ms T = 100ms, 200ms, 300ms, 3.1s.

The following description references the sequence numbers in Figure 3.4.

10529-I

Chapter Summary

Following a block transfer write (1) the module inhibits communication until after it has loaded the new configuration data (2), scanned the inputs and/or outputs (3), and filled the data buffer (4). Configuration block transfers, therefore, should only be performed when the module is being configured or calibrated.

Any time after the buffer is filled (4), a block transfer read (BTR) request can be acknowledged.

When operated in the default mode, new data will be available for a BTR every 50 milliseconds. When operated in real time sample mode (RTS = T), BTRs will be ignored by the module for “T” milliseconds, at which time a single BTR will be allowed.

In this chapter, you learned how to program your programmable controller. You were given sample programs for your PLC-2, PLC-3 and PLC-5 family processors.

You also read about module scan time.

3-5

Configuring Your Module

Chapter

Objectives

Configuring Your Input Module

In this chapter you will read how to:

configure your module’s hardware condition your inputs enter your configuration data.

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. Data is conditioned through a group of data table words that are transferred to the module using a block transfer write instruction. Before continuing, make

sure you read “Setting Voltage/Current Selection Jumpers” in chapter 2.

The software configurable features available with the Isolated Analog Input Module (1771-IL series B) are:

input range selection data format digital filtering real time sampling scaling to engineering units high and low alarms

Configure your module for its intended operation by means of your programming terminal and block transfer write (BTW) instructions.

Note: Programmable controllers that use 6200 software programming tools can take advantage of the IOCONFIG utility to configure this module. IOCONFIG uses menu-based screens for configuration without having to set individual bits in particular locations. Refer to your 6200 software literature for details.

Note: Programmable controllers that use process configuration and operation software (cat. no. 6190-PCO) can take advantage of those development and runtime tools used for the application of programmable controllers in process control. The PCO worksheets and the menu-driven configuration screens and faceplates let you configure, test/debug and operate the I/O module. Refer to your 6190-PCO software literature for details.

4-1

Chapter 4

Module Configuration

During normal operation, the processor transfers from 1 to 37 words to the module when you program a BTW instruction to the module’s address. The BTW file contains configuration words, high and low channel alarm settings, and calibration values for each channel.

When a block transfer write length of 0 is programmed, the 1771-IL series B will respond with the Series A default length of 19.

Input Range Selection

Individual inputs are configurable to operate with any one 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). Two bits are allocated for each channel. For example, for channel 1, set bits 00 and 01 as follows:

able 4.A

Bit

Settings for V

Bit 01 Bit 00 Voltage or current input

0 0 1 to 5 V DC, 4 to 20 mA 0 1 0 to 5 V DC, 0 to 20 mA 1 0 -5 to +5 V DC, -20 to +20 mA 1 1 -10 to +10 V DC, 0 to 10 V DC

Current

input mode selected by configuration plug.

Configurable

oltage or Current Inputs

using bipolar scaling.

The 1771-IL/B has 16-bit resolution across the +10V range. For compatibility purposes, the default scaling for all ranges is 12-bits (0-4095 or +4095). This allows the series B module to be directly interchangeable with the series A module. To use the full 16-bit capability, scaling values must be changed. Refer to “Scaling” later in this chapter.

4-2

Table 4.B shows the incremented voltage or current assigned to each bit for the seven different input ranges. For example, if the channel 1 input range is 0 to +5V and the actual incoming signal is at mid-range (+2.5V) the value in the module’s data word, if using default scaling, would be 0000 1000 0000 0000 (binary) or 2048 (decimal). The input (default scaling) is 2048/4096, or 1/2 of full scale.

Chapter 4

Module Configuration

able 4.B

Input Voltage and Current Ranges for the Analog Input Module

Nominal Voltage

or Current Range

+1 to +5V 0000 to +4095 0.98mV 3063 to 15316 0.33mV

0 to 5V 0000 to +4095 1.22 mV 32768 to 15316 0.33mV

-5 to +5V -4095 to +4095 1.22mV -15316 to 15316 0.33mV

-10 to +10V -4095 to +4095 2.44mV -30632 to 30632 0.33mV 0 to +20mA 0000 to +4095 0.0049mA 0 to 15316 0.0013mA

+4 to +20mA 0000 to +4095 0.0039mA 3063 to 15316 0.0013mA

-20 to +20mA -4095 to +4095 0.0049mA -15316 to 15316 0.0013mA

Note: V

oltage and current input ranges are selectable on a per channel basis.

Default Scaling

BCD Output Range

Voltage or

Current Per Bit

Data from

A/D Converter

Voltage or

Current Per Bit

To get the same resolution available from the A/D converter, scale each channel as shown in Table 4.C.

able 4.C

Scaling

Endpoints

Voltage/Current

Range

Minimum

Scaling Endpoint

Maximum

Scaling Endpoint

Block T

ransfer W

rite Format

+1 to 5V 3063 15316 4 to 20mA 3063 15316 0 to 5V 0 15316 0 to 20mA 0 15316

-5 to 5V -15316 15316

-20 to 20mA -15316 15316

-10 to 10V -30632 30632 0 to 10V -30632 30632

You select the format to enter values in the block transfer write table. Bit 08 (10 octal) of BTW word 2 sets the parameters for scaling, high and low alarms, and the digital filter constant.

Decimal Bit 08

Octal Bit 10

0 BCD (default) BCD 1 Two’s Complement Binary Two’s Complement Binary

BTW Data Format You must enter all values in:

4-3

Chapter 4

Module Configuration

Data Format

Digital Filtering

You must also indicate what format will be used to read data from your module. Typically, BCD is selected with PLC-2 processors, and 2’s complement binary is selected with PLC-3 and PLC-5 processors. See Appendix C for details on data format.

able 4.D

Selecting

the Data Format

Decimal Bit 10

(Octal Bit 12)

0 0 BCD 0 1 not used 1 0 two’s complement binary 1 1 signed magnitude binary

Decimal Bit 09

(Octal Bit 11)

Data Format

The analog input 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.

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 4.2), you can see that when the digital filter constant time elapses, 63.2% of the total response is reached. Each additional time constant achieves 63.2% of the remaining response.

4-4

Figure 4.1 Digital

Filter Equation

Yn = Y

Where:

- Y

n-1

t + TA

n = present output, filtered peak voltage (PV)

n –1 = previous output, filtered PV

t = module channel update time (seconds)

TA = digital filter time constant (seconds)

n = present input, unfiltered PV

n-1

)

Figure 4.2 Digital

Amplitude

Chapter 4

Module Configuration

Filter Lag Equation Illustration

100%

63%

Real Time Sampling

0 0.01 0.5 0.99 Time in Seconds

Unfiltered Input TA = 0.01 sec TA = 0.5 sec TA = 0.99 sec

16723

Digital filter time constant values of .00 BCD to .99 BCD (0.00 to 2.55 binary) (.00 = no filter) are set in bits 00 through 07 of word 3 of the block transfer write instruction. If an invalid digital filter value is entered (i.e., .1F BCD), the invalid filter value bit in the block transfer read status area will be set. If an invalid digital filter value is entered, the module will not perform digital filtering. If you choose to use the digital filtering feature, the filter time constant value chosen will apply to all input signals.

The real time sampling (RTS) mode of operation provides data gathered at precisely timed intervals for use by the processor.

Use RTS for time based functions (such as PID and totalization) in the PLC. RTS allows accurate time based calculations in local or remote I/O racks. In the RTS mode the module scans and updates its inputs at a user defined time interval (T) instead of the default interval. The module ignores block transfer read (BTR) requests for data until the sample time period elapses. The BTR of a particular data set occurs only once at the end of the sample period and subsequent requests for transferred data are ignored by the module until a new data set is available. If a BTR does not occur before the the end of the next RTS period, a time-out bit is set in the BTR status area. When set, this bit indicates that at least one data set was not transferred to the processor. (The actual number of data sets missed is unknown.) The time-out bit is reset at the completion of the next BTR.

4-5

Chapter 4

Module Configuration

Set appropriate bits in the BTW data file to enable the RTS mode. You can select RTS periods ranging from 50 ms to 3.1 seconds in increments of 100ms for the 1771-IL/B. Refer to Table 4.E below for actual bit settings. Note that the default mode of operation is implemented by placing all zeroes in bits 11 through 15 (13 through 17 octal).

able 4.E

Examples

of Bit Settings for the Real T

ime Sample Mode

Decimal Bits 15 14 13 12 11

Octal Bits 17 16 15 14 13

0 0 0 0 0 No RTS, Default settings: 50ms 0 0 0 0 1 100ms 0 0 0 1 0 200ms 0 0 0 1 1 300ms 0 0 1 0 0 400ms 0 0 1 0 1 500ms 0 0 1 1 0 600ms 0 0 1 1 1 700ms 0 1 0 0 0 800ms 0 1 0 0 1 900ms 0 1 0 1 0 1.0s 0 1 1 1 1 1.5s 1 0 1 0 0 2.0s 1 1 0 0 1 2.5s 1 1 1 1 0 3.0s

Sample Time Period

4-6

1 1 1 1 1 3.1s

Chapter 4

Module Configuration

Scaling

Each channel has two scaling points, low and high. The signal value at these points is fixed. For example, the high scaling point of a +10V output channel always corresponds to an input signal equal to +10.000V.

To implement the scaling feature, you insert the minimum and maximum scaled values in the appropriate configuration words.

The format of the scaling values is determined by the BTW format bit (bit 08, word 2). The range in BCD format is +9999. The range in binary format is +32767.

For example, assume that at 0mA, the device connected to this input channel is producing 0 psi, and at 20mA it produces 150 psi, and the 1771-IL/B range selected is 4 to 20mA. Extrapolation indicates that at 4mA, the device is producing 30 psi. By setting the low scale value of the input to 30 and the high scale value to 150, this input channel will report data in psi. For better resolution, you can multiply both of the scaling values by the same multiplier as long as both scale values are in the range of +9999 BCD or +32767 binary. By setting the low scale to 3000 and the high scale value to 15000, you would report data in units of 0.01 psi per count.

Maximum resolution can be obtained by setting the low scale value to

-9999 in BCD and the high scale value to +9999 in BCD (-32767 low and +32767 high in binary).

For example, if in the 1 to 5V mode, the scaling points are 1 and 5 volts. If you set the scaling to +32767, the maximum the module will display will be 32767. If 5.1V is applied, the display will be 32767 and the overrange bit for that channel will be set.

Note: To achieve the 0 to +10V range you must use bipolar scaling. Select

10V range and scale for + the actual intended range. If you need 0 to

the + 100 gpm, set scaling values at -100 and +100. You will effectively be creating a 0 to 10V range that is scaled from 0 to 100.

Implementing the Scaling Feature

You implement the scaling feature by:

1. Inserting minimum and maximum scaled values in the appropriate

configuration words

2. If using BCD, and any of the minimum or maximum values are

negative, set the appropriate sign bits in the minimum or maximum sign bit words.

4-7

Chapter 4

Module Configuration

Scaling Ranges

The maximum range of the scaling values is +9999 BCD or +32767 binary. These values must be entered in the format selected in word 2, bit 08 (10).

If invalid values are entered into the scaling words, the corresponding input in the BTR data will be zero and the invalid scaling bit will be set.

able 4.F

Default

Scaling V

Input Range Default Scaling Value

-10 to +10V

-5 to +5V 0 to 5V 1 to 5V

alues

-4095 to +40

0 to +40

If scaling and alarms are not selected, the module still requires specific BTR and BTW file lengths for the number of channels used. Table 4.G shows the required BTR and BTW file lengths.

able 4.G

Block Transfer Read and Write File Lengths (with no scaling or alarms)

Channels Used BTR File Length BTW File Length

1 5 5

2 6 7 3 7 9 4 8 11 5 9 13 6 10 15 7 11 17 8 12 19

Important: Use decimally addressed bit locations for PLC-5 processors.

4-8

Chapter 4

Module Configuration

Alarms

Each input channel has alarm functions that provide status indication through associated status bits in the block transfer read data returned by the module.

Underrange alarm - This bit is set if the input falls below the minimum range for that specific input type. This alarm is predefined and cannot be changed by the user. In current loop inputs, this bit also indicates an open loop.

Overrange alarm - This bit is set if the input rises above the maximum range for that specific input type. This alarm is predefined and cannot be changed by the user. For all voltage inputs, this bit indicates an open channel.

Range

1 to 5V/4 to 20mA 1V dc or 4mA 5V dc or 20mA 0 to 5V/0 to 20mA Zero 5V dc or 20mA

-5 to 5V/-20 to 20mA -5V dc or -20mA 5V dc or 20mA

-10 to +10V -10V dc +10V dc

User-defined alarms let the user specify a range of “good” input values. If the input value goes outside of this range, the module will set the low or high alarm bit for that channel. The alarm values are written to the module in the same units as the scaling values. Valid alarm values are +9999 BCD or +32767 binary. If you select “no alarms” you must set both the low alarm value and the high alarm value to zero. If either the low or high alarm for a channel is not zero, alarms for that channel are enabled.

Figure 4.3 Alarm

Example

Overrange Limit

User-Defined High Alarm Limit

Input Channel

Underrange Bit is set

when the input signal is

less than:

Overrange Bit is set

when the input signal is

greater than:

alarm inactive

alarm active

User-Defined Low Alarm Limit

Underrange Limit

Time

4-9

Chapter 4

Module Configuration

Default Configuration

Decimal Bits 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

Octal Bits 17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00

Word

If a write block with all zeroes is written to the module, the default selections will be:

1 to 5V dc or 4 to 20mA (depends on voltage/current selection jumper) BCD data format no real time sampling (RTS) no digital filter no scaling no alarms

Note: Input data is set to 0 until an initial block transfer write is received by the module.

Figure 4.4 Word

Assignments for the Isolated Analog Input Module

(1771-IL series B)Block T

Range Selection Bits for Channels 1 through 8

8 7 6 5 4 3 2 1

ransfer W

rite

2 Real Time Sampling

8 7 6 5 4 3 2 1 8 7 6 5 4 3 2 1

Sign bits, maximum scaling values Sign bits, minimum scaling values 4 Channel 1 - minimum scaling 5 Channel 1 - maximum scaling 6 Channel 2 - minimum scaling 7 Channel 2 - maximum scaling 8 Channel 3 - minimum scaling 9 Channel 3 - maximum scaling

10 Channel 4 - minimum scaling 11 Channel 4 - maximum scaling 12 Channel 5 - minimum scaling 13 Channel 5 - maximum scaling 14 Channel 6 - minimum scaling 15 Channel 6 - maximum scaling

Data

Format

BTW

Format

Digital Filter

16 Channel 7 - minimum scaling

4-10

Chapter 4

Module Configuration

17 Channel 7 - maximum scaling 18 Channel 8 - minimum scaling 19 Channel 8 - maximum scaling

00010203040506070809101112131415Decimal Bits

00010203040506071011121314151617Octal Bits

8 7 6 5 4 3 2 1 8 7 6 5 4 3 2 1

Sign bits, high alarm values 21 Channel 1 - Low Alarm Value 22 Channel 1 - High Alarm Value 23 Channel 2 - Low Alarm Value 24 Channel 2 - High Alarm Value 25 Channel 3 - Low Alarm Value 26 Channel 3 - High Alarm Value 27 Channel 4 - Low Alarm Value 28 Channel 4 - High Alarm Value 39 Channel 5 - Low Alarm Value 30 Channel 5 - High Alarm Value 31 Channel 6 - Low Alarm Value 32 Channel 6 - High Alarm Value 33 Channel 7 - Low Alarm Value 34 Channel 7 - High Alarm Value

Sign bits, low alarm values

35 Channel 8 - Low Alarm Value 36 Channel 8 - High Alarm Value

8 7 6 5 4 3 2 1 Not Used S G O

Inhibit bits for calibration Calibration bits

4-11

Chapter 4

Module Configuration

Word

Bit/Word Descriptions for the Isolated Analog Input Module Configuration Block

Note that decimal bits are shown. Octal bits are shown in parentheses.

Decimal

Bit

(Octal Bit)

Description

Word 1

Word 2

Word

Word 4

Word 5

Bits 00-15

(00-17)

Bits 00-07 Digital filter reduces effect of noise on the input. See “Digital Filtering.”

Bit 08 (10)

Bits 09-10

(11-12)

Bits 11-15

(13-17)

Bits 00-07

Bits 08-15

(10-17)

Bits 00-15

(00-17)

Bits 00-15

(00-17)

Input range selections, grouped 2 bits for each channel, allow selection of any of 7 input voltage or current ranges. See Table 4.A.

BTW format bit. This bit determines the format for scaling, digital filter constant, and high and low alarms. Bit 08 (10) = 0 - Values must be entered in BCD Bit 08 (10) = 1 - Values must be entered in Two’s Complement Binary

Data format is used to match format of processor. See Table 4.D.

Real time sampling defaults to 50ms if zeroes are entered. See Table 4.E

for other real time sample intervals. Minimum sign bits, when set, designate minimum scaling values that are

negative in BCD. Default = 0 - positive. Maximum sign bits, when set, designate maximum scaling values that are

negative in BCD. Default = 0 - positive. Minimum scaling values for channel 1. Enter in format selected in word 2,

bit 08 (10). Valid entries are between +9999 and -9999 in BCD; -32767 and +32767 in binary. Default = 0 - no scaling.

Maximum scaling values for channel 1. Enter in format selected in word 2, bit 08 (10). Valid entries are between +9999 and -9999; -32767 and +32767 in binary. Default = 0 - no scaling.

Words 6-19

Word 20

Word 21

Word 22

Words 23

thru 36

4-12

Bits 00-15

(00-17)

Bits 00-07

Bits 08-15

(10-17)

Bits 00-15

(00-17)

Bits 00-15

(00-17)

Bits 00-15

(00-17)

Minimum and maximum scaling values for channels 2 through 8. Enter in format selected in word 2, bit 08 (10). Valid entries are between +9999 and

-9999; -32767 and +32767 in binary. Default = 0 - no scaling.

Low alarm sign bits. These bits are only used when BCD format is chosen in word 2, bit 08 (10). When a bit is set (1), the low alarm value for

that channel is negative. Default is bit reset (0), positive.

High alarm sign bits. These bits are only used when BCD format is chosen in word 2, bit 08 (10). When a bit is set (1), the high alarm value for

that channel is negative. Default is bit reset (0), positive. Low alarm value for channel 1. This represents the value at which the low

alarm bit for channel 1 (word 13 of the BTR) will be set. High alarm value for channel 1. This represents the value at which the high

alarm bit for channel 1 (word 14 of the BTR) will be set.

Low and high alarm values for channels 2 thru 8.

Chapter 4

Module Configuration

Chapter Summary

Word

Decimal Bit

(Octal Bit)

Offset Calibration bit. When this bit is set (1), offset calibration is to be

Bit 00

Bit 01

Bit 02

Bits 03-07 Not used. Bits 08-15

(10-17)

performed. When set, no other calibration function bits can be set. Default is 0, no offset calibration.

Gain Calibration bit. When this bit is set (1), gain calibration is to be performed. When set, no other calibration function bits can be set. Default is 0, no gain calibration.

Save calibration values. When this bit is set (1), new calibration values will be saved in EEPROM. Default = 0, values not saved.

Inhibit Channel Calibration. When this bit is set (1), that particular channel will not be calibrated. Default = 0, all channels to be calibrated.

Description

In this chapter you learned how to configure your module’s hardware, condition your inputs and enter your data.

4-13

Chapter

Module Status and Input Data

Chapter

Objectives

Reading Data From Your Module

Decimal Bits 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00

Octal Bits 17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00

Word 1 Not used A HF IA IF RTS IS OR PU Status word

2 Not used 8 7 6 5 4 3 2 1 Underrange bits - Channels 1-8 3 Not used 8 7 6 5 4 3 2 1 Overrange bits - Channels 1-8 4 Not used 8 7 6 5 4 3 2 1 Polarity bits - Channels 1-8

In this chapter you will read about:

reading data from your module block transfer read data format

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 5.1 Word

Assignments for the Isolated Analog Input Module

(1771-IL series B) Block Transfer Read

5 Channel 1 Input Channel 1 Input 6 Channel 2 Input Channel 2 Input 7 Channel 3 Input Channel 3 Input 8 Channel 4 Input Channel 4 Input

9 Channel 5 Input Channel 5 Input 10 Channel 6 Input Channel 6 Input 11 Channel 7 Input Channel 7 Input 12 Channel 8 Input Channel 8 Input 13 Not used 8 7 6 5 4 3 2 1 Low Alarm Bits 14 Not used 8 7 6 5 4 3 2 1 High Alarm Bits 15 8 7 6 5 4 3 2 1 CF EF Not used S G O Calibration Status Bits

5-1

Chapter 5

Module Status and Input Data

The Isolated Analog Input Module (1771-IL series B) reports the status of all eight channels to the processor as outlined below.

able 5.A Bit/Word Read Block Transfer Data

Word

Descriptions for the Isolated Analog Input Modules (1771-IL)

Decimal

Bit

(Octal Bit)

Bit 00

Power up bit (PU) is set after initial power up. It will not reset until the module receives a valid write block transfer.

Note: Input data is set to zero until the first BTW is received.

Description

Word 1

Word

Bit 01

Bit 02

Bit 03

Bit 04

Bit 05

Bit 06

Bit 07

Bits 08-15

(10-17)

Bits 00-07

Bits 08-15

(10-17)

Out of range bit (OR) is set if one or more channels are either over or under range.

Invalid scaling bit (IS) is set if the firmware cannot use the scaling data in the BTW. Acceptable values are between -9999 and +9999 in BCD, and -32767 to +32767 in binary.

Real time sample (RTS) time out bit is set if the module is using RTS and a block transfer read has not occurred within the programmed RTS period.

Invalid Filter bit (IF) is set if the filter parameters are not correct. The value must be between 00 and 99 (0.00 and 0.99 seconds) in BCD; or 0 and 255 (0 to 2.55) in binary.

Invalid Alarm bit (IA) is set if any alarm value is unusable, such as

expecting BCD and value is in 2’s complement binary. Hardware Failure bit (HF) is set if the analog module has an internal

hardware failure (such as fuse blown or open, etc.). Alarm violation status bit (A) is set if one or more channels are in an

alarm condition.

Not used

Individual underrange bits for each channel. Bit 00 for channel 1, bit 01 for channel 2, etc.

Not used

Bits 00-07

Word

Word 4

Word

Word 5 thru 12 Input data values. Word 5 for channel 1, word 6 for channel 2, etc.

5-2

Bits 08-15

(10-17)

Bits 00-07

Bits 08-15

(10-17)

Individual overrange bits for each channel. Bit 00 for channel 1, bit 01 for channel 2, etc.

Not used

Polarity (sign) bits are set when the input is less than zero in both BCD and signed magnitude data formats. Bit 00 for channel 1, bit 01 for channel 2, etc.

Not used

Chapter 5

14 15

Module Status and Input Data

Word

Word 13

Word

Word 14

Word

Decimal Bit

(Octal Bit)

Bits 00-07

(00-07)

Bits 08-15

(10-17)

Bits 00-07

(00-07)

Bits 08-15

(10-17)

Bit 00

Bit 01

Bit 02

Bits 03-05 Not used

Bit 06

Low Alarm bits for channels 1 through 8 respectively. Each bit represents an alarm indicator for that channel. When the bit is set, the value of that channel is below the low alarm value.

Not used

High Alarm bits for channels 1 through 8 respectively. Each bit represents an alarm indicator for that channel. When the bit is set, the value of that channel is above the high alarm value.

Not used

Offset Calibration Complete (O). When this bit is set, the offset calibration request was successfully completed.

Gain Calibration Complete (G). When this bit is set, the gain calibration request was successfully completed.

Save Complete (S). When this bit is set, the “save calibration values to EEPROM” was successfully completed.

EEPROM Fault (EF). When this bit is set, the calibration values could not be saved to EEPROM.

Description

Chapter Summary

Calibration Fault (CF). When this bit is set, the module could not

Bit 07

Bits 08-15

(10-17)

perform offset or gain calibration. This bit is set when a save is requested.

Calibration Inhibited. Each bit represents a channel that was not calibrated, either due to an error or a user request. If the channel was requested not to be calibrated, these bits confirm that request.

In this chapter you learned the meaning of the status information that the input module sends to the processor.

5-3

Module Calibration

Chapter

Objective

Tools and Equipment

Tool or Equipment Description Model/Type Available from:

Precision Voltage Source

Industrial Terminal and Interconnect Cable

Calibrating your Input Module

In this chapter we tell you how to calibrate your module.

To calibrate your input module you will need the following tools and equipment:

0-10V, 1µV resolution; Accuracy of better than 2mV

Programming terminal for A-B family processors

The analog input module is shipped already calibrated. If it becomes necessary to recalibrate the module, you must calibrate the module in an I/O chassis. The module must communicate with the processor and industrial terminal.

Before calibrating the module, you must enter ladder logic into the processor memory, so that you can send data to the module (BTW), and the processor can read data from the module (BTR).

Analogic 3100, Data Precision 8200 or equivalent

Cat. No. 1770-T3 or Cat. No. 1784-T45, -T47, -T50, etc.

Allen-Bradley Company Highland Heights, OH

About Auto-calibration

Calibration is accomplished using a method called “auto-calibration.”

Auto-calibration calibrates the input by generating offset and gain correction values and storing them in EEPROM in the module. These values are read out of EEPROM and placed in RAM memory at initialization of the module.

The auto-calibration routine operates as follows:

- Whenever a block transfer write (BTW) of length 37 is performed to the module (any time after the module has been powered up), it interrogates word 37 for a request for auto-calibration.

- The request can be for the following: offset calibration, gain calibration, save operation (save to EEPROM). Note that only one bit may be set at one time. To completely calibrate the module, three BTWs must be sent: one for each offset, gain and save operations.

6-1

Chapter 6

Module Calibration

Performing Auto-calibration

Calibration of the module consists of applying 0.00000V across each input channel for offset calibration, and +10.00000V across each input channel for gain correction.

ATTENTION: Verify that each channel’s configuration jumper is set to the voltage mode (refer to “Setting the Voltage/Current Selection Jumpers” in chapter 2.) Failure to do so can damage the module.

Offset Calibration

Normally all inputs are calibrated together. To calibrate the offset of an input, proceed as follows:

1. Verify that each channel has its jumper set for voltage mode. (Refer to

“Setting the Voltage/Current Selection Jumper” in chapter 2. Check the position of the jumper on each channel.

2. Apply power to the module.

3. Connect shorting links, or apply 0.00000V across each input channel on

the 1771-WF field wiring arm as shown in Figure 6.1.

Figure 6.1 Shorting

erminal Identification

Inputs for Offset Calibration

Channel 1

17 16

Channel 2

15 14

Channel 3

13 12

Channel 4

11 10

Not used

Channel 5

7 6

Channel 6

5 4

Channel 7

3 2

Channel 8

18 17 16 15 14 13

9 8

7 6 5 4 3 2 1

Shorting link.

Repeat for each channel

Short each input, or apply 0.00000V across each input channel.

Apply

0.00000V

6-2

Wiring Arm

Cat. No. 1771-WF

10530-I

Chapter 6

Module Calibration

4. After the connections stabilize, request the offset calibration by setting bit

00 in block transfer write word 37 and sending a block transfer write (BTW) to the module. Refer to Table 6.A.

When the BTW is sent, all channels are calibrated to 0.00000V.

able 6.A

Write

Block T

ransfer W

ord 28

Decimal Bit

Octal Bit

Word 37

Decimal Bit

Octal Bit

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

Inhibit Calibration Requested Auto-Calibration

8 7 6 5 4 3 2 1 Set these bits to 0

Requested

Save

Values

Requested

Gain Cal.

Requested

Offset Cal.

NOTE: Normally, all channels are calibrated simultaneously (decimal bits 08-15; octal bits 10-17 of word 37 are 0). To disable calibration on any channel, set the corresponding bit 08 through 15 decimal, or 10 through 17 octal, of word 37.

5. Queue block transfer reads (BTRs) to monitor for offset calibration

complete and any channels which may have not calibrated successfully. Refer to Table 6.B.

able 6.B

Read

Block T

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

ransfer W

ord 13

Word 13

Uncalibrated Channels Auto-Calibration Status

Cal.

8 7 6 5 4 3 2 1

Fault

EEPROM

Fault

Not used

6. Reset bit 00 (0) (requested offset calibration).

7. Proceed to Gain Calibration below.

Save to EEPROM Complete

Gain Cal. Complete

Offset

Cal.

Complete

6-3

Chapter 6

Module Calibration

Gain Calibration

Calibrating gain requires that you apply +10.00000V across each input channel.

To calibrate the gain of an input, proceed as follows: NOTE: Normally, all channels are calibrated simultaneously (decimal bits

08015, octal bits 10-17 of word 37 are 0). To disable calibration on any channel, set (1) the corresponding bit 08-15 decimal (10-17 octal) of word 37.

1. Apply +10.00000V across each input channel as shown in Figure 6.2.

Figure 6.2 Applying

10.00000V for Gain Calibration

erminal Identification

Channel 1

17 16

Channel 2

15 14

Channel 3

13 12

Channel 4

11 10

Not used

Channel 5

7 6

Channel 6

5 4

Channel 7

3 2

Channel 8

Wiring Arm

Cat. No. 1771-WF

18 17

16 15 14 13

9 8

7 6

5 4 3 2 1

Apply

10.00000V

10531-I

6-4

2. After the connections stabilize, request the gain calibration by setting bit

01 in BTW word 37 and sending a block transfer write (BTW) to the module. Refer to Table 6.A.

When the BTW is sent, all channels are calibrated to +10.00000V.

3. Queue BTRs to monitor for gain calibration complete and any channels

which may not have calibrated successfully.

Chapter 6

Module Calibration

Save Calibration Values

If any ”uncalibrated channel” bits 08-15 (10-17 octal) of word 15 are set, a save cannot occur. Auto-calibration should be performed again, starting with offset calibration. If the module has a faulty channel, the remaining functioning channels can be calibrated by inhibiting calibration on the faulty channel.

The module can be run with the new calibration values, but will lose them on power down. To save these values, proceed as follows:

1. Request a “save to EEPROM” by setting bit 02 in BTW word 37 and

sending the BTW to the module. Refer to Table 6.A.

2. Queue BTRs to monitor for “save complete”, “EEPROM fault” and

“calibration fault.” An EEPROM fault indicates a nonoperative EEPROM; a calibration fault indicates at least one channel was not properly offset or gain calibrated and a save did not occur.

Chapter Summary

In this chapter, you learned how to calibrate your input module.

6-5

Troubleshooting

Chapter

Objective

Diagnostics Reported by the Module

We describe how to troubleshoot your module by observing indicators and by monitoring status bits reported to the processor.

At powerup, the module momentarily turns on both indicators as a lamp test, then checks for

correct RAM operation EPROM operation EEPROM operation a valid write block transfer with configuration data

Thereafter, the module lights the green RUN indicator when operating without fault, or lights the red FAULT indicator when it detects fault conditions. If the red FAULT indicator is on, block transfers will be inhibited.

The module also reports status and specific faults (if they occur) in every transfer of data to the programmable controller processor. Monitor the green and red indicators and status bits in word 1 of the BTR file when troubleshooting your module.

Figure 7.1 Module

Indicators

ISOLATED

ANALOG INPUT

RUN

FLT

Green RUN Indicator

Red FLT (fault) Indicator

10528-I

7-1

Chapter 7

Troubleshooting

Troubleshooting with the Indicators

Indication Probable Cause Recommended Action

RUN FLT

Both RUN and FLT are OFF

Red FLT indicator ON and Green RUN indicator is ON

Red FLT indicator ON

Table 7.A shows indications, probable causes and recommended actions to correct common faults.

able 7.A

Troubleshooting

No power to module

Possible short on the module LED driver failure

Microprocessor, oscillator or EPROM failure

If immediately after power-up, indicates RAM or EPROM failure.

If during operation, indicates possible microprocessor or backplane interface failure.

Hardware failure (blown fuse, etc.)

Chart for the Isolated Analog Input Module (1771-IL series B)

Check power to I/O chassis. Recycle as necessary.

Replace module

Replace module.

RUN FLT

Green RUN indicator is flashing

When red LED is on, the watchdog timer has timed out and backplane communications are terminated. Y

Status Reported by the Module

Powerup diagnostics successfully completed. Normal operation. If indicator continues to flash, and write block

transfers (BTW) cannot be accomplished, you have a possible interface failure.

Replace module.

our user program should monitor communication.

Status Reported in Word 1

Design your program to monitor status bits in the lower byte of word 1, and to take appropriate action depending on your application requirements. You may also want to monitor these bits while troubleshooting with your industrial terminal. The module sets a bit (1) to indicate it has detected one or more of the following conditions as shown in Table 7.B.

7-2

Word

able 7.B

Status

Reported in W

Decimal

Bit

(Octal Bit)

Power up bit (PU) is set after initial power up. It will not reset until the

Bit 00

module receives a valid write block transfer.

Note: Input data is set to zero until the first BTW is received.

Chapter 7

Troubleshooting

ord 1

Description

Word 1

Bit 01

Bit 02

Bit 03

Bit 04

Bit 05

Bit 06

Bit 07 Alarm bit (A) is set if there is an alarm indication on any channel.

Out of range bit (OR) is set if one or more channels are either over or under range.

Invalid scaling bit (IS) is set if the firmware cannot use the scaling data in the BTW. Acceptable values are between -9999 and +9999 in BCD, and -32767 to +32767 in binary.

Real time sample (RTS) time out bit is set if the module is using RTS and a block transfer read has not occurred within the programmed RTS period.

Invalid Filter bit (IF) is set if the filter parameters are not correct. The value must be between 00 and 99 (0.00 and 0.99 seconds) in BCD; or 0 and 255 (0 to 2.55) in binary.

Invalid Alarm bit (IA) is set if any alarm value is unusable, such as

expecting BCD and value is in 2’s complement binary. Hardware Failure bit (HF) is set if the analog module has an internal

hardware failure (such as blown fuse, etc.).

Status Reported in Words 2 and 3

Design your program to monitor over/under range bits, and to take appropriate action depending on your application requirements. You may also want to monitor these bits while troubleshooting with your industrial terminal.

Bits 00-07 each represent an input for channels 1-8, respectively. For example, bit 04 represents input channel 5. The module sets a bit (1) to indicate it has detected an out of range condition. Refer to Table 7.C.

able 7.C

Status

Reported in W

Decimal

Word

Word 2 Bits 00-07

Word 3 Bits 00-07

Bit

(Octal Bit)

ords 2 and 3

Description

Individual underrange bits for each channel. Bit 00 for channel 1, bit 01 for channel 2, etc.. If input connections and voltages are correct, this status may indicate failed channel communications with the microprocessor. If all channels are underrange, this indicates a possible dc/dc converter failure or a blown fuse.

Inputs overrange. Bit 00 is channel 1, bit 07 is channel 8. If input connections and voltages are correct, this status may indicate a hardware failure.

7-3

Chapter 7

Troubleshooting

Status Reported in Words 13 and 14

Design your program to monitor over/under alarm bits, and to take appropriate action depending on your application requirements. You may also want to monitor these bits while troubleshooting with your industrial terminal.

Bits 00-07 each represent an input for channels 1-8, respectively. For example, bit 04 represents input channel 5. The module sets a bit (1) to indicate it has detected an alarm condition. Refer to Table 7.D.

able 7.D

Status

Word

Reported in W

Decimal

(Octal Bit)

Bit

ords 13 and 14

Description

Word 13

Word 14

Bits 00-07

(00-07)

Bits 00-07

(00-07)

Low Alarm bits for channels 1 through 8 respectively. Each bit represents an alarm indicator for that channel. When the bit is set, the value of that channel is below the low alarm value.

High Alarm bits for channels 1 through 8 respectively. Each bit represents an alarm indicator for that channel. When the bit is set, the value of that channel is above the high alarm value.

7-4

Chapter 7

Troubleshooting

Status Reported in Word 15

Design your program to monitor status bits in word 15 during auto-calibration, and to take appropriate action depending on your requirements. You may also want to monitor these bits while troubleshooting with your industrial terminal. The module sets a bit (1) to indicate it has detected one or more of the following conditions as shown in Table 7.E.

able 7.E

Status

Word

Reported in W

Decimal

(Octal Bit)

Bit

ord 15

Description

Chapter Summary

Word

Bit 00

Bit 01

Bit 02

Bits 03-05 Not used

Bit 06

Bit 07

Bits 08-15

(10-17)

Offset Calibration Complete (O). When this bit is set, the offset calibration request was successfully completed.

Gain Calibration Complete (G). When this bit is set, the gain calibration request was successfully completed.

Save Complete (S). When this bit is set, the “save calibration values to EEPROM” was successfully completed.

EEPROM Fault (EF). When this bit is set, the calibration values could not be saved to EEPROM.

Calibration Fault (CF). When this bit is set, the module could not perform offset or gain calibration. This bit is set when a save is requested.

Calibration Inhibited. Each bit represents a channel that was not calibrated (bit 08 (10) - channel 1, bit 09 (11) - channel 2 and so on). This bit is set either due to an error or a user request. If the channel was requested not to be calibrated, these bits confirm that request.

In this chapter, you learned how to interpret the status indicators, status words and troubleshoot your input module.

7-5

Appendix

Specifications

Inputs per module 8 fully isolated differential 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

Input current ranges (nominal) +4 to +20mA

0 to +20mA

-20 to +20mA Resolution 16-bit binary over full range Accuracy Voltage: Typical - 0.01% of full scale range @ 25oC

Maximum - 0.05% of full scale range @ 25oC

Current: Typical - 0.06% of full scale range @ 25

Linearity +1 LSB Repeatability +1 LSB Isolation Voltage +1000V peak, channel to channel, channel to ground for 1s Input overvoltage protection voltage mode: 140V ac (rms) continuous;

current mode: 8V dc continuous

Unscaled BCD and binary output data to the processor

Input impedance >10 megohms for voltage ranges; 250 ohms for current ranges Common mode rejection >120 db @ 60Hz and 1K ohm source imbalance Common mode impedence >50 megohms shunted by <5 nF Normal mode rejection >120 db @ 60Hz Current Requirements 1.0A @ +5V from I/O chassis backplane Open Circuit Detection Voltage mode: Open input produces upscale reading.

Time to Detect Open Circuit 10 seconds maximum Calibration Auto-calibration (offset and gain)

Power Dissipation 6.5 Watts maximum Thermal Dissipation 22.2 BTU/hr maximum Engineering units sent to

processor

0000 to +409510 for unipolar ranges (0 to 5V, +1 to +5V, 0 to +20mA, and +4 to +20mA)

-4095

5V, +10V, +20mA input ranges

Current mode: Open input produces zero reading.

Zero offset and gain adjustment for each channel via programming terminal Verify every six months for maintaining absolute accuracy

+9999 BCD with selectable scaling +32767 binary

Maximum - 0.1% of full scale range @ 25 (Includes 0.05% when using internal current resistor)

to 409510 for bipolar ranges

Continued on next page

A-1

Appendix

Specifications

Specifications continued

Calibration Interval calibration should be checked at 6 month intervals to maintain

specified accuracy Internal scan rate 50 milliseconds for 8 channels Environmental conditions

operational temperature: storage temperature: relative humidity

0 to 600C (32 to 1400F)

-40 to 850C (-40 to 1850F

Operating: 5 to 95% (without condensation)

Non-operating: 5 to 80% (without condensation) Conductors Wiring

Sample Configuration of the Analog Input Module

The following is a sample configuration for the 1771-IL series B isolated analog input module. Entering the data shown in Figure B.1 in the configuration words of the write block transfer data file will result in the following module setup.

Overall Module Functions Chosen

Digital Filter Time Constant 0.5 seconds Data Format 2’s Complement Binary Real Time Sampling Rate 1.5 seconds

Individual Channel Functions Chosen

Input

Range

Channel 1 1-5V 1000/5000 Channel 2 1-5V -5000/-1000 Channel 3 0-5V 0000/5000 Channel 4 0-5V -5000/0000 Channel 5 +5V -2500/2500

Scale Value

Low/High (counts)

Channel 6 +5V -5000/5000 Channel 7 +10V -100/100 Channel 8 +10V -9999/9999

The above configuration for the 1771-IL/B isolated analog input module would be set up using the following PLC-5 data table file (Figure B.1).

B-1

Appendix B

Configuration Example

Figure B.1 Sample

PLC-5 Data File (Hexadecimal Data) for an Isolated Analog Input

Module (cat. no. 1771-IL series B)

0000 0019 0000

0000 0000

0000

FA50

0000

0000 0000

0000

09BD

0000

0000 0000

0000

7C50

2500

0000 0000

Address

N10:00 N10:10 N10:20

N10:30 N10:40 N10:50 N10:60 N10:70 N10:80 N10:90 N10:100 N10:110 N10:120 N10:130 N10:140

The block transfer read starts at N10:00.

The block transfer write starts at N10:70.

000A

0000 0000

0000 0000 0000 0000 0000 00000000000000000000 0000 0000

0000 1000 5000 0000 0000 0000 0000 0000 00000000000000000000

0000 0000 0000 0000 0000 00000000000000000000 0000 0000

0000 0000

09C2

0000 0000

0000 5000 5000

0000 0000

0000 0000 0000

0000 0000

0000

02FA

2500

0000 0000

F246609B97F632804E0909BE

0000 0000

0000 5000 0100

0000 0000

0000 1000 0100

0000 0000

0000 0000 9999

0000 0000

0000 5000 9999

0000 0000

0000 5000 0000

0000 0000

B-2

Data Table Formats

Appendix

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 2

, 21, 22 and 23 (Table C.A). The decimal equivalent for a group of four binary digits is determined by multiplying the binary digit by its corresponding place value and adding these numbers.

Figure C.1 4-Digit

Binary Coded Decimal

0 X 23 = 0

0 X 2

= 0

0 X 21 = 0

1 X 20 = 1

0001001000111001

0 X 2

0 X 2 1 X 21 = 2

0 X 20 = 0

= 0 = 0

0 X 2

= 0

0 X 2 1 X 21 = 2

1 X 20 = 1

1 X 2

= 8

0 X 22 = 0 0 X 21 = 0

1 X 2

= 1

12955-I

C-1

Appendix C

Data Formats

able C.A

BCD

Representation

Signed-magnitude Binary

Place V

(8) 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

(4) 2

alue

(2) 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. It cannot be used to manipulate binary 12-bit values or negative values.

Example: The following binary number is equal to decimal 22.

Two’s Complement Binary

10110

= 22

The signed-magnitude method places an extra bit (sign bit) in the left-most position and lets this bit determine whether the number is positive or negative. The number is positive if the sign bit is 0 and negative if the sign bit is 1. Using the signed magnitude method:

0 10110 = +22 1 10110 = -22

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.

10110

= 22

C-2

Appendix C

Data Formats

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. The number is positive if the sign bit is 0 and negative if the sign bit is 1. Using the complement method:

0 10110 = 22

To get the negative using the two’s complement method, you must invert each bit from right to left after the first “1” is detected.

In the above example:

0 10110 = +22

Its two’s complement would be:

1 01010 = -22

Note that in the above representation for +22, starting from the right, the first digit is a 0 so it is not inverted; the second digit is a 1 so it is not inverted. All digits after this one are inverted.

If a negative number is given in two’s complement, its complement (a positive number) is found in the same way:

1 10010 = -14 0 01110 = +14

All bits from right to left are inverted after the first “1” is detected.

The two’s complement of 0 is not found, since no first “1” is ever encountered in the number. The two’s complement of 0 then is still 0.

C-3

Appendix

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.

For multiple GET instructions, individual rungs of ladder logic are used instead of a single rung with a block transfer instruction. A sample rung using multiple GET instructions is shown in Figure D.1 and described in the following paragraphs.

Rung 1: This rung is used to set four conditions.

Examine On Instruction (113/02) - This is an optional instruction. When

used, block transfers will only be initiated when a certain action takes place. If you do not use this instruction, block transfers will be initiated every I/O scan.

First GET Instruction (030/120) - identifies the module’s physical address

(120) by rack, group and slot; and where in the accumulated area of the data table this data is to be stored (030).

Second GET Instruction (130/060) - indicates the address of the first word

of the file (060) that designates where the data will be transferred. The file address is stored in word 130, 100

above the data address.

Output Energize Instruction (012/07) - enables the block transfer read

operation. If all conditions of the rung are true, the block transfer read enable bit (07) is set in the output image data table control byte. The output image table control byte contains the read enable bit and the number of words to be transferred. The output energize instruction is defined as follows:

- “0” indicates that it is an output instruction

- “1” indicates the I/O rack address

- “2” indicates the module group location within the rack

- “07” indicates this is a block transfer read operation (if this were a block transfer write operation, “07” would be replaced by “06”.)

D-1

Appendix D

Block Transfer (Mini–PLC–2 and PLC–2/20 Processors)

Output Image Table

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.

Rung Summary: Once the block transfer read operation is complete, the processor automatically sets bit 07 in the input image table status byte and stores the block length of the data transferred.

Figure D.1 Multiple

GET Instructions (Mini-PLC-2 and PLC-2/20 Processors Only)

010

Data Table

1 R

Control Byte

012

017

Output Image Table Control

Byte Contains Read Enable Bit and Block

Length in Binary Code

Timer/Counter

Accumulated Values Area

Input

Image

Table

Timer/Counter

Preset

Values Area

Multiple GET Instructions

Rung 1

Rung 2

Rung 3

113

030

120

060

130

060

Status

Byte

027 030

060

065

110

112

117

130

Data Address Contains Module

Address in BCD

First Address, Destination of

Transferred Data

Input Image Table Status Byte Contains Done Bit

Storage Location Contains File Address in BCD

R = Read 07 = Bit

012

12172

D-2

Appendix D

Block Transfer (Mini–PLC–2 and PLC–2/20 Processors)

Setting the Block Length (Multiple GET Instructions only)

For Block Transfer Active Operations Only

Output Image Table

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.

For example, Figure D.2 shows if your input module is set up to transfer 6 words, you would set bits 01 and 02 of the lower image table control byte. The binary equivalent of 6 words is 000110. You would also set bit 07 when programming the module for block transfer read operations. Bit 06 is used when block transfer write operations are required.

Figure D.2 Setting

Block Length (Multiple GET Instructions only)

1 R

Read 6 Words

from Module

Control

Byte

010

012

017

Output Image Table Control

Byte Contains Read Enable Bit and Block

Length in Binary Code

Block Transfer

Read Enable Bit

10000110

Data Table

Number of Words

toTransfer

Default 0 0 0 0 0 0

1 0 0 0 0 0 1 2 0 0 0 0 1 0 3 0 0 0 0 1 1 4 0 0 0 1 0 0 5 0 0 0 1 0 1 6 0 0 0 1 1 0

18 0 1 0 0 1 0 19 0 1 0 0 1 1

Lower Output Image Table Byte

04 03 02 01 00

: :

027 030

Binary Bit Pattern

Data Address Contains Module

Address in BCD

D-3

Index

alarms, 4-9

overrange, 4-9 underrange, 4-9

BCD format, 1-3 bit settings, voltage or current input,

4-2 block transfer, 1-1, 2-2, 3-1

write, 4-5

block transfer read, 3-1, 3-2, 5-1

word assignments, 5-1 block transfer write, 3-2 BTR format, bit/word descriptions,

5-2

Calibration, tools, 6-1 communication, 1-2 configuration, default, 4-10 configuration block, 4-10

bit/word descriptions, 4-12 configuration BTW, 3-1 configuring your module, 4-1 connecting wiring, 2-5

data formats

2’s complement binary, C-2

4–digit binary coded decimal, C-1

signed–magnitude binary, C-2 default configuration, 4-10 description of module, 1-1 Diagnostics

indicators, 7-1

reported by module, 7-1

electrostatic discharge, 2-1

features, 1-1 field wiring arm, 2-5 filtering, 4-4

grounding, 2-7

indicator lights, 2-8 input range, selection, 4-2 installation, of module, 2-4

keying bands, 2-4

module features, 1-1 module installation, 2-4 module location in the I/O chassis,

2-2

noise interference, 2-2

power requirements, 2-2 pre–installation considerations, 2-1 programming, with multiple GETs,

D-1 programming example

PLC–2, 3-2 PLC–3, 3-3 PLC–5, 3-4

ranges, input voltage and current, 4-3 real time sampling, 4-5 RTS bit settings, 4-6

Index

scaling

implementation, 4-7

ranges, 4-8 scan time, 3-5 specifications, A-1

Troubleshooting, table, 7-2

update time, 1-1

wiring connections, 2-6

PLC is a registered trademark of Allen-Bradley Company, Inc. PLC-5 is a trademark of Allen-Bradley Company, Inc. SLC is a trademark of Allen-Bradley Company, Inc.

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9551

15–76

Rockwell Automation 1771-ILB, D17716.5.91 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Important User Information

Summary of Changes

Module Descriptions

Features

How Analog Modules Communicate with Programmable Controllers

Accuracy

Chapter Summary

Before You Install Your Input Module

Electrostatic Damage

Power Requirements

Module Location in the I/O Chassis

Setting the Voltage/Current Selection Jumpers

Installing the Analog Module

Connecting Wiring to Your Input Module

Grounding

Indicator Lights

Chapter Summary

Block Transfer Programming

PLC-2 Programming

PLC-3 Programming

PLC-5 Programming

Chapter Summary

Configuring Your Input Module

Input Range Selection

Data Format

Digital Filtering

Real Time Sampling

Scaling

Default Configuration

Chapter Summary

Reading Data From Your Module

Chapter Summary

Tools and Equipment

Calibrating your Input Module

About Auto-calibration

Performing Auto-calibration

Chapter Summary

Diagnostics Reported by the Module

Troubleshooting with the Indicators

Status Reported by the Module

Chapter Summary

Specifications

Sample Configuration of the Analog Input Module

4-Digit Binary Coded Decimal (BCD)

Signed-magnitude Binary

Two’s Complement Binary

Setting the Block Length (Multiple GET Instructions only)

Index