Spectrum Controls 1756sc-OF8H User Manual

Owner’s Guide 0300196-02 Rev. E

™

C

ONTROL

A

NALOG

Catalog Numbers: 1756sc-IF8H, 1756sc-OF8H

L

OGIX

M

HART

ODULES

Important Notes

1) PLEASE DOWNLOAD LATEST SAMPLE PROJECT FROM

OUR WEBSITE AT (www.spectrumcontrols.com).

2) Please read all the information in this owner’s guide before installing
the product.

3) The information in this owner's guide applies to hardware Series A and
firmware version 1.0 or later.

4) This guide assumes that the reader has a full working knowledge of the
relevant processor.

Notice

The products and services described in this owner's guide are useful in a
wide variety of applications. Therefore, the user and others responsible
for applying the products and services described herein are responsible
for determining their acceptability for each application. While efforts
have been made to provide accurate information within this owner's
guide, Spectrum Controls assumes no responsibility for the accuracy,
completeness, or usefulness of the information herein.

Under no circumstances will Spectrum Controls be responsible or liable
for any damages or losses, including indirect or consequential damages
or losses, arising out of either the use of any information within this
owner's guide or the use of any product or service referenced herein.

No patent liability is assumed by Spectrum Controls with respect to the
use of any of the information, products, circuits, programming, or
services referenced herein.

The information in this owner's guide is subject to change without notice.

Limited Warranty

Spectrum Controls warrants that its products are free from defects in
material and workmanship under normal use and service, as described in
Spectrum Controls literature covering this product, for a period of 1 year.
The obligations of Spectrum Controls under this warranty are limited to
replacing or repairing, at its option, at its factory or facility, any product
which shall, in the applicable period after shipment, be returned to the
Spectrum Controls facility, transportation charges prepaid, and which
after examination is determined, to the satisfaction of Spectrum Controls,
to be thus defective.

This warranty shall not apply to any such equipment which shall have
been repaired or altered except by Spectrum Controls or which shall
have been subject to misuse, neglect, or accident. In no case shall the
liability of Spectrum Controls exceed the purchase price. The
aforementioned provisions do not extend the original warranty period of
any product which has either been repaired or replaced by Spectrum
Controls.

Table of Contents

Preface xi

Module Overview
1

Installing and
Wiring Your Module
7

Who Should Use This Guide .................................................................................. xi

What This Guide Covers ......................................................................................... xi

Related Allen-Bradley Documents .......................................................................... xi

Table A. Related Allen-Bradley documents ............................................................ xi

Terms & Abbreviations You Should Know ............................................................. xii

General Description .................................................................................................. 1

Table 1.2 1756sc-OF8H Output Ranges .................................................................. 2

Table 1.3 Hardware Features .................................................................................... 2

System Overview ...................................................................................................... 3

Table 1.4 Recommendations to minimize interference from radiated electrical noise4

Power Requirements ................................................................................................. 7

Table 2.1 Maximum current drawn by the module ................................................... 7

Using your module in the ControlLogix System ...................................................... 8

Module Installation and Removal ............................................................................ 8

Preventing Electrostatic Discharge .......................................................................... 9

Removal and Insertion Under Power ....................................................................... 9

Compliance to European Union Directives ............................................................ 10

Figure 2.1 (Module insertion into a rack) ............................................................... 11

Figure 2.2 (Terminal block diagram with keying) .................................................... 12

Wiring Your Module .............................................................................................. 12

Preparing and Wiring the Cables ........................................................................... 13

Terminal Block Layout

................................................................................................................................14

Wiring Inputs to the IF8H Module ........................................................................ 14

Wiring Outputs to the OF8H Module .................................................................... 15

Operation Within the
ControlLogix
System 19

Ownership and Connections .................................................................................. 19

Using RSNetWorx and RSLogix 5000 ..................................................................... 19

Direct Connections ................................................................................................. 20

Module Operation .................................................................................................. 20

Modules in a Local Chassis ................................................................................... 21

Requested Packet Interval (RPI) ............................................................................ 21

Modules in a Remote Chassis ................................................................................ 22

Listen-Only Mode .................................................................................................. 22

Multiple Owners of Input Modules ....................................................................... 23

Configuration Changes in an Input Module with Multiple Owners ...................... 24

vi ControlLogix™ Universal Analog Input Modules

Configuring RSLogix
5000 For The IF8H
and OF8H 25

Module Installation ................................................................................................ 25

Adding Your Module to a Project .......................................................................... 25

Configuration Tags Overview ................................................................................ 31

Input Tags Overview .............................................................................................. 34

Output Tags Overview

(OF8H Only) ........................................................................................................... 35

Configuration, Data,
and Status Tags
for the 1756sc-IF8H
37

Send Configuration Data to the Module ................................................................ 37

Configuration Tags for the 1756sc-IF8H ................................................................ 38

Table 5.1a ................................................................................................................ 38

Table 5.1b ................................................................................................................ 39

Table 5.1c ................................................................................................................ 40

Table 5.1d ................................................................................................................ 41

Module Filter Selection .......................................................................................... 41

Input Tags .............................................................................................................. 44

Table 5.3a ................................................................................................................ 44

Table 5.3b ................................................................................................................ 45

Table 5.3c ................................................................................................................ 46

Table 5.3d ................................................................................................................ 47

Accessing The Module Tags ................................................................................. 47

Changing Configuration Information at the Tags .................................................. 49

Configuration, Data,
and Status Tags
for the 1756sc-OF8H
51

Send Configuration Data to the Module ................................................................ 51

Configuration Tags for the 1756sc-OF8H .............................................................. 52

Table 6.1a ................................................................................................................ 52

Table 6.1b ................................................................................................................ 53

Table 6.1c ................................................................................................................ 54

Table 6.1d ................................................................................................................ 55

Table 6.1e ................................................................................................................ 56

Table 6.1f................................................................................................................. 57

Input Tags .............................................................................................................. 57

Table 6.2a ................................................................................................................ 58

Table 6.2b ................................................................................................................ 59

Table 6.2c ................................................................................................................ 60

Table 6.2d ................................................................................................................ 61

Output Tags ............................................................................................................ 61

Table 6.3.................................................................................................................. 61

Accessing The Module Tags ................................................................................. 62

Changing Configuration Information at the Tags .................................................. 64

Enabling and Using
HART on the
1756sc-IF8H and
OF8H 67

Table of Contents vii

Configuring the Modules for HART ...................................................................... 67

Figure 7.1 (Channel 0 Configuration Example) ....................................................... 68

Figure 7.2 (Channel 0 Configuration Example) ....................................................... 69

How the Modules Send and Receive HART Data ................................................. 69

Figure 7.3 (Primary, Secondary and Slave connection).......................................... 70

Figure 7.4 (Connected and Unconnected messaging) ........................................... 71

Figure 7.5 (Auto Acquisition Flow)........................................................................ 72

Table 7.1(Packet 0) .................................................................................................. 73

Table 7.2(Packet 1) .................................................................................................. 74

Table 7.3 (Packet 2) ................................................................................................. 75

Table 7.4 (Packet 3) ................................................................................................. 76

Table 7.5 (Packet 4) ................................................................................................. 76

Figure 7.6 (Demultiplexing Ladder) ........................................................................ 77

Figure 7.7 (Message Instruction) ........................................................................... 78

Table 7.6 (Generic CIP Configuration) .................................................................... 79

Figure 7.8 (Message Configuration Dialog) ........................................................... 79

Table 7.7 (Get HART Device Information Command) ............................................ 80

Table 7.8 (Response If Device Information Is Not Available) ................................ 80

Table 7.9 (Response When Device Information Is Available) ............................... 81

Figure 7.9 (Sending a Module Specific Command Using Ladder) ......................... 82

Table 7.10 (HART Suspend and Resume Command) ............................................. 83

Table 7.11 (HART Suspend and Resume Reply Packet) ........................................ 83

Table 7.12 (HART Pass-Through Command Request) .......................................... 85

Table 7.13 (HART Pass-Through Command Request Reply) ................................ 86

Table 7.14 (HART Pass-Through Command Complete Query) .............................. 87

Table 7.15 (HART Pass-Through Command Complete Query Reply) ................... 87

Table 7.16 (HART Pass-Through Command Complete Query - Reply Packet

Structure) ................................................................................................................ 88

Figure 7.10a (HART Pass-Through Request and Query Process) ........................ 90

Figure 7.10b (HART Pass-Through Request and Query Process) ........................ 91

Figure 7.10c (HART Pass-Through Request and Query Process) ........................ 92

Figure 7.10d (HART Pass-Through Request and Query Process) ........................ 93

Figure 7.10e (HART Pass-Through Request and Query Process) ........................ 94

HART Protocol Overview....................................................................................... 94

Figure 7.11 (HART Message Structure) ................................................................. 94

Table 7.17 (Start Character Definition) ................................................................... 95

Figure 7.18 (Long Frame Address) ......................................................................... 96

Sending a HART Command to a Field Device via Pass-through........................... 97

Figure 7.19 .............................................................................................................. 98

Figure 7.20 .............................................................................................................. 98

Programming
Examples 99

Initial Programming ................................................................................................. 99

Figure 8.1 (Sample Ladder Logic) ......................................................................... 100

Demultiplexing HART Data .................................................................................. 104

Figure 8.2 (IF8H Demultiplexing Ladder) .............................................................. 104

Figure 8.3 (OF8H Demultiplexing Ladder) ............................................................ 105

Sending HART Commands Using the MSG Instruction ..................................... 106

viii ControlLogix™ Universal Analog Input Modules

Figure 8.3a (IF8H HART Message Ladder) .......................................................... 106

Figure 8.3b (IF8H HART Message Ladder) ......................................................... 107

Figure 8.3c (IF8H HART Message Ladder) .......................................................... 108

Figure 8.3d (IF8H HART Message Ladder) ......................................................... 109

Figure 8.3e (IF8H HART Message Ladder) .......................................................... 110

Figure 8.4a (OF8H HART Message Ladder) ........................................................ 111

Figure 8.4b (OF8H HART Message Ladder)........................................................ 112

Figure 8.4c (OF8H HART Message Ladder) ........................................................ 113

Figure 8.4d (OF8H HART Message Ladder)........................................................ 114

Figure 8.4e (OF8H HART Message Ladder) ........................................................ 115

Swap Byte Ladder ................................................................................................ 115

Figure 8.5 (Converting a FLOAT Value To Its 4 byte HART Equivalent)............ 115

Converting Unpacked ASCII to Packed ASCII .................................................... 116

Figure 5.6a (Packed ASCII)................................................................................... 117

Figure 5.6b (Packed ASCII) .................................................................................. 118

Troubleshooting
119

Using Module Indicators to Troubleshoot .......................................................... 119

Using RSLogix 5000 to Troubleshoot Your Module ............................................ 120

Module Configuration Errors ............................................................................... 121

Maintaining Your
Module
And Ensuring Safety
129

1756sc-IF8H Module
Specifications 133

1756sc-OF8H
Module
Specifications

135

Programming Your
Module 137

Additional HART
Protocol Information
143

Preventive Maintenance ...................................................................................... 129

Safety Considerations .......................................................................................... 129

Electrical Specifications

1756sc-IF8H .......................................................................................................... 133

Specifications

1756sc-OF8H ........................................................................................................ 135

Module Installation .............................................................................................. 137

Adding Your Module to a Project ........................................................................ 137

Overview ............................................................................................................... 143

Message Structure ............................................................................................... 144

Universal Commands ............................................................................................ 146

Common Practive Commands ............................................................................... 148

Status .................................................................................................................... 152

Response Codes ................................................................................................... 152

Declaration of Conformity .................................................................................... 155

Table of Contents ix

x ControlLogix™ Universal Analog Input Modules

Who Should Use
This Guide

Preface

Read this preface to familiarize yourself with the rest of the owner’s
guide. This preface covers:

• who should use this guide

• what this guide covers

• related Allen-Bradley documents

• terms & abbreviations you should know

Use this guide if you design, install, program, or maintain a control system
that uses Allen-Bradley ControlLogix Controllers.

You should have a basic understanding of ControlLogix products. You
should also understand electronic process control and the ladder program
instructions required to generate the electronic signals that control your
application. If you do not, contact your local Allen-Bradley representative
for the proper training before using these products.

What This Guide
Covers

Related Allen­Bradley Documents

This guide covers the 1756sc-IF8H and 1756sc-OF8H analog input and
output modules with HART protocol. It contains the information you need
to install, wire, use, and maintain these modules. It also provides diagnostic
and troubleshooting help should the need arise.

Table A lists several Allen-Bradley documents that may help you as you
use these products.

Table A. Related Allen-Bradley documents

Allen-Bradley Doc. No. Title Publication Number

1756-PA72, ControlLogix Power Supply Installation

-PB72 Instructions 1756-5.1

1756-A4, ControlLogix Chassis Installation Instructions 1756-5.2

-A7, -A10,

-A13, -A17

xii ControlLogix™ Analog HART Modules

1756 Series ControlLogix Module Installation Instructions
(Each module has separate document for installation) 1756-5.5,

1756-L1, Logix5550 Controller User Manual 1756-6.5.12

-L1M1, -L1M2

1756-DHRIO ControlLogix Data Highway Plus
Communication Interface Module User Manual 1756-6.5.2

1756-ENET ControlLogix Ethernet Communication Interface
Module User Manual 1756-6.5.1

To obtain a copy of any of the Allen-Bradley documents listed, contact
your local Allen-Bradley distributor.

Terms &
Abbreviations You
Should Know

You should understand the following terms and abbreviations before using
this guide.

-5.42

A/D - Refers to analog-to-digital conversion. The conversion produces a
digital value whose magnitude is proportional to the instantaneous
magnitude of an analog input signal.

Attenuation – The reduction in magnitude of a signal as it passes through
a system. The opposite of gain.

Channel – Refers to one of eight, small-signal analog input interfaces to
the module’s terminal block. Each channel is configured for connection to
a input device, and has its own configuration and status words.

Chassis – The component in which the I/O resides. The backplane
connection is facilitated through a series of connectors that mate to the I/
O.

Common mode rejection ratio (CMRR) - The ratio of a device’s
differential voltage gain to common mode voltage gain. Expressed in dB,
CMRR is a comparative measure of a device’s ability to reject
interference caused by a voltage common to its terminal relative to
ground.

Common mode voltage – The voltage difference between the negative
terminal and analog common during normal differential operation.

Cut-off frequency - The frequency at which the input signal is attenuated
3 dB by the digital filter. Frequency components of the input signal that

Preface xiii

are below the cut-off frequency are passed with under 3 dB of attenuation
for low-pass filters.

Channel Update Time -

dB (decibel) – A logarithmic measure of the ratio of two signal levels.

Digital filter - A low-pass mathmatic single order filter applied to the A/

D signal. The digital filter provides high-frequency noise rejection.

Effective resolution – The number of bits in the channel data word that
do not vary due to noise.

HART - Highway Addressable Remote Transducer

Local System - A control system with I/O chassis within several feet of

the processor.

LSB (least significant bit) – The bit that represents the smallest value
within a string of bits.

Multiplexer – A switching system that allows several input signals to
share a common A/D converter.

Normal mode rejection (differential mode rejection) – A logarithmic
measure, in dB, of a device’s ability to reject noise signals between or
among circuit signal conductors, but not between the equipment grounding
conductor or signal reference structure and the signal conductors.

Module update time – The amount of time that one data acquisition
cycle takes place and it reported to the PLC processor.

Remote system - A control system where the chassis can be located
several thousand feet from the processor chassis. Chassis communication
is via the 1756-CNB or 1756-ENET Adapter.

Resolution – The smallest detectable change in a measurement, typically
expressed in engineering units (e.g. 0.15 °C) or as a number of bits. For
example, a 12-bit system has 4096 possible output states. It can therefore
measure 1 part in 4096. See also effective resolution.

Sampling time - The time required by the A/D converter to sample an
input channel.

xiv ControlLogix™ Analog HART Modules

Step response time – The time required for the A/D signal to reach 95%
of its expected, final value, given a full-scale step change in the output
data word.

Tags - Identifiers for configuration, data, and status information found
within the module. Tags allow the user to modify specific module
attributes and view data and status.

Unconnected Message - A ControlNet-based message that is sent
without intervention with the PLC controller.

Update time – The time for the module to sample and convert a channel
input signal and make the resulting value available to the ControlLogix
processor.

Chapter 1

Module Overview

This chapter describes the functionality of the modules and explains how
the ControlLogix controller reads/writes analog data from the modules and
how HART data is derived from the modules. Read this chapter to
familiarize yourself further with your analog module. This chapter covers:

• general description and hardware features

• an overview of system and module operation

General Description

This module is designed exclusively for use in the Allen-Bradley
ControlLogix 1756 I/O rack systems. The HART input module, 1756sc­IF8H, stores digitally converted volt (V) and milliamp (mA) analog data
and HART field instrument data in its image table for retrieval by all
ControlLogix processors. The HART output module, 1756sc-OF8H,
produces voltage or current output for control and maintains a dialog with
HART-compatible field instruments

Following is a list of features available on the IF8H and OF8H modules
that allow their use in a wide variety of applications.

· Removal and insertion under power (RIUP) - a system feature that
allows you to remove and insert modules while chassis power is applied

· Producer/consumer communications - an intelligent data exchange
between modules and other system devices in which each module
produces data without having been polled

· Rolling time stamp of data - 15 bit module-specific rolling timestamp with
millisecond resolution which indicates when data was sampled/applied.
This timestamp may be used to calculate the interval between channel
updates.

· System timestamp of data - 64 bit system clock places a timestamp on
the transfer of data between the module and its owner controller within
the local chassis

· IEEE 32 bit floating point format

· On-Board Features, such as custom User Scaling, Process Alarms, Rate
Alarms, Digital Filtering, and Under/Overrange Detection

· User Calibration - analog I/O modules may be calibrated by the user to
accommodate application related errors.

· Class I/Division 2, UL, CSA, CE, and FM Agency Certification

2 ControlLogix™ Analog HART Modules

Input Ranges

The following tables provide compatibility information on the supported
millivolt and voltage input and output types supported by the modules.

Table 1.1 1756sc-IF8H Input Ranges

Table 1.2 1756sc-OF8H Output Ranges

0 to 5 V (0 to +5.125 V)

0 to 10 V (0 to +10.25 V)

-10 to +10 V (-10.25 to +10.25 V)

4 to 20 mA (3.42 to +20.58 mA)

0 to 20 mA (0 to +20.58 mA)

-10 to +10 V (-10.4 to +10.4 V)

0 to 20 mA (0 to +21.5 mA)

Eight channels are individually configurable for voltage or current input/
output types. Each channel provides wire-off input, over-range, and
under-range detection and indication, when enabled.

Hardware Features

The modules fit into any single slot within a ControlLogix modular system.
The modules use a unique generic profile which may be configured using
your RSLogix 5000 programming software.

The modules utilize a removable terminal block, that provides connections
for the eight channels. The module is configured through RSLogix 5000
software, defining current or voltage inputs/outputs.

Table 1.3 Hardware Features

Hardware Function

OK LED Displays communication and fault status

Cal LED Displays a calibration related condition

Side Label (Nameplate) Provides module information

Removable Terminal Block Electrical connection to devices

Door Label Permits easy terminal identification

Self Locking Tabs Secure module in chassis slot

Terminal Block Switch Locks the RTB to the module.

Chapter 1: Module Overview 3

Diagnostic LEDs

The modules contain diagnostic LEDs that help you identify the source of
problems that may occur during power-up or during normal operation.
Power-up and diagnostics are explained in Chapter 9, Testing Your
Module.

System Overview

The modules communicate with the ControlLogix processor and receive
+5 Vdc and +24 Vdc power from the system power supply through the
backplane interface. You may install as many modules in the system as
the power supply can support.

The 1756sc-IF8H has 8 channels that can receive voltage and current
signals from volt or milliamp devices. When configured for volt or
milliamp analog inputs, the module converts the analog values directly into
floating point values. For those input types, the module assumes that the
input signal is linear prior to input into the module.

The 1756sc-OF8H has 8 channels that can output volt or millivolt signals
to drive field sensors.

Both modules support HART communication. Communication is
independent of the analog acquisition and control phase.

System Operation

At power-up, the modules check internal circuits, memory, and basic
functions. During this time the Cal LED remains on. If the module does
not find any faults, it turns off the Cal LED.

After completing power-up checks, the modules wait for a connection to
an owner controller then valid channel configuration data from your ladder
logic program. After channel configuration data is transferred, and one or
more channels are enabled, the module channels are available to your
ladder program.

Each time the 1756sc-IF8H reads an input channel, the module tests that
data for a fault, i.e. over-range, or under-range condition. If it detects an
open-circuit (wire off), over-range or under-range condition, the module
sets a unique bit in the status tags.

4 ControlLogix™ Analog HART Modules

Module Operation

The 1756sc-IF8H module’s input circuitry consists of eight differential­ended analog inputs, multiplexed to two A/D converters. The A/D
converters read the analog input signals and convert them to floating point
values.

The 1756sc-OF8H has 8 channels that are routed to two quad D/A
converters which output the control signal.

HART communication is independent of the analog operation. Each of the
eight channels are multiplexed to one modem.

Compatibility with Current Devices and Cables

The modules are compatible with a variety of voltage and current devices
with an input or output 0-5V, 0-10V, ±10V, 0-20mA, and 4-20mA.

To minimize interference from radiated electrical noise, we recommend
twisted-pair and highly shielded cables such as the following:

Table 1.4 Recommendations to minimize

interference from radiated electrical noise

For This Type of Device We Recommend This Cable (or equivalent)

V, mA devices Belden 8761, shielded, twisted-pair

Chapter 1: Module Overview 5

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6 ControlLogix™ Analog HART Modules

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Chapter 2

Installing Installing

Installing

Installing Installing

Read this chapter to install and wire your module. This chapter covers:

• avoiding electrostatic damage

• determining power requirements

• installing the module

• wiring signal cables to the module’s terminal block

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:

and and

and

and and

WW

iring iring

W

iring

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iring iring

YY

our Moduleour Module

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our Module

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our Moduleour Module

Power Requirements

The module receives its power through the ControlLogix chassis
backplane from the fixed or modular +5 VDC and +24 VDC chassis
power supply. The maximum current drawn by the module is shown in
the table below.

Table 2.1 Maximum current drawn by the module

Module 5VDC Amps 24VDC Amps

1756sc-IF8H 0.300 0.070

1756sc-OF8H 0.200 0.230

8 ControlLogix™ Analog HART Modules

Using your module in
the ControlLogix
System

Place your module in any slot of a ControlLogix chassis or modular
expansion chassis.

An analog I/O module translates an analog signal into or from a
corresponding digital representation which controllers can easily operate
on for control purposes.

A ControlLogix I/O module mounts in a ControlLogix chassis and uses a
Removable Terminal Block (RTB) to connect all field-side wiring.

Before you install and use your module you should have already:

· installed and grounded a 1756 chassis and power supply.

· ordered and received an RTB for your application.

Important: RTBs are not included with your module purchase.

Specify Allen Bradley Part Number:

1756sc-IF8H - 1756-TBCH - 36 position screw terminals

1756-TBS6H - 36 position press terminals
1492-AIFM8-3
1492-ACABLE-UC (Differential Voltage)
1492-ACABLE-UD (Differential Current)

Module Installation and
Removal

1756sc-OF8H - 1756-TBNH - 20 position screw terminals

1756-TBSH - 20 position press terminals
1492-AIFM8-3
1492-ACABLE-WB

When installing the module in a chassis, it is not necessary to remove the
terminal blocks from the module. However, if the terminal blocks are

Preventing
Electrostatic
Discharge

Chapter 2: Installing And Wiring Your Module 9

removed, use the write-on label located on the side of the terminal blocks
to identify the module location and type.

This module is sensitive to electrostatic discharge.

ATTENTION: Electrostatic discharge can damage integrated circuits or

!

semiconductors if you touch backplane connector pins. Follow these guidelines when

you handle the module:

· Touch a grounded object to discharge static potential

· Wear an approved wrist-strap grounding device

· Do not touch the backplane connector or connector pins

· Do not touch circuit components inside the module

· If available, use a static-safe work station

· When not in use, keep the module in its static-shield box

Removal and Insertion
Under Power

These modules are designed to be installed or removed while chassis
power is applied.

ATTENTION: When you insert or remove a module while backplane power is

!

applied, an electrical arc may occur. An electrical arc can cause personal injury or

property damage by:

· sending an erroneous signal to your system’s field devices causing unintended

machine motion or loss of process control.

· causing an explosion in a hazardous environment.

Repeated electrical arcing causes excessive wear to contacts on both the module and

its mating connectors. Worn contacts may create electrical resistance that can affect

module operation.

10 ControlLogix™ Analog HART Modules

Compliance to
European Union
Directives

If this product bears the CE marking, it is approved for installation within
the European Union and EEA regions. It has been designed and tested to
meet the following directives.

EMC Directive

This product is tested to meet Council Directive 89/336/EEC
Electromagnetic Compatibility (EMC) and the following standards, in
whole or in part, documented in a technical construction file:

EN 61010-1 and EN 61131-2, EN61000-6-2:2001, EN61000-6-4:2001
EN61010-1:2001

This product is intended for use in an industrial environment.

Low Voltage Directive

This product is tested to meet Council Directive 73/23/EEC Low Voltage,
by applying the safety requirements of EN 61131-2 Programmable
Controllers, Part 2 - Equipment Requirements and Tests.

For specific information required by , EN61131-2:1994 + A11:1996 +
A12:2000, see the appropriate sections in this publication, as well as the
following Allen-Bradley publications:

· Industrial Automation Wiring and Grounding Guidelines For Noise
Immunity, publication 1770-4.1

· Automation Systems Catalog, publication B111

This equipment is classified as open equipment and must be installed
(mounted) in an enclosure during operation as a means of providing
safety protection.

CAUTION

!

POSSIBLE EQUIPMENT OPERATION

ATTENTION: The module is designed to support Removal and Insertion Under

Power (RIUP). However, when you remove or insert an RTB with field-side

power applied, unintended machine motion or loss of process control can occur.

Exercise extreme caution when using this feature.

Chapter 2: Installing And Wiring Your Module 11

WARNING

!

These modules are to be used only with the Allen-Bradley 1756 ControlLogix

System.

To insert your module into the rack, follow these steps:

1. Align the circuit board of your module with the card guides at the top
and bottom of the chassis.

Figure 2.1 (Module insertion into a rack)

2. Key the RTB in positions that correspond to unkeyed module
positions. Insert the wedge-shaped tab on the RTB with the rounded
edge first. Push the tab onto the RTB until it stops.

Keying the Removable Terminal Block

Key the RTB to prevent inadvertently connecting the incorrect RTB to
your module.

When the RTB mounts onto the module, keying positions will match up.
For example, if you place a U-shaped keying band in position #4 on the
module, you cannot place a wedge-shaped tab in #4 on the RTB or your
RTB will not mount on the module.

We recommend that you use a unique keying pattern for each slot in the
chassis.

12 ControlLogix™ Analog HART Modules

1. Insert the U-shaped band with the longer side near the terminals. Push
the band onto the module until it snaps into place.

Figure 2.2 (Terminal block diagram with keying)

Wiring Your Module

Follow these guidelines to wire your input signal cables:

• Power, input, and output (I/O) wiring must be in accordance with
Class 1, Division 2 wiring methods [Article 501-4(b) of the National
Electrical Code, NFPA 70] and in accordance with the authority
having jurisdiction.

• Peripheral equipment must be suitable for the location in which it is
used.

• Route the field wiring away from any other wiring and as far as
possible from sources of electrical noise, such as motors,
transformers, contactors, and ac devices. As a general rule, allow at
least 6 in. (about 15.2 cm) of separation for every 120 V of power.

• Routing the field wiring in a grounded conduit can reduce electrical
noise further.

• If the field wiring must cross ac or power cables, ensure that they
cross at right angles.

• To limit the pickup of electrical noise keep signal wires as far from
power and load lines as possible.

• For improved immunity to electrical noise, use Belden 8761 (shielded,
twisted pair) or equivalent wire for millivolt sensors

Preparing and Wiring
the Cables

Chapter 2: Installing And Wiring Your Module 13

• Ground the shield drain wire at only one end of the cable. The
preferred location is at the shield connections at the ControlLogix
chassis. (Refer to IEEE Std. 518, Section 6.4.2.7 or contact your
sensor manufacturer for additional details.)

• Keep all unshielded wires as short as possible.

• To limit overall cable impedance, keep input cables as short as
possible. Locate your I/O chassis as near to the sensors as your
application will permit.

• Tighten screw terminals with care. Excessive tightening can strip a
screw.

• Follow system grounding and wiring guidelines found in your
ControlLogix Installation and Operation Manual.

To prepare and connect cable leads and drain wires, follow these steps:

1. At each end of the cable, strip some casing to expose individual wires.

2. Trim signal wires to 5-inch lengths beyond the cable casing. Strip
about 3/16 inch (4.76 mm) of insulation to expose the ends of the
wires.

3. At the module-end of the cables (see figure above):

- extract the drain wire and signal wires

- remove the foil shield

- bundle the input cables with a cable strap

4. Connect pairs of drain wires together, Channels 0 and 1, Channels 2
and 3, Channels 4 and 5, Channels 6 and 7. Keep drain wires as short
as possible.

5. Connect the drain wires to the grounding lug on the PLC chassis.

6. Connect the signal wires of each channel to the terminal block.
Important: Only after verifying that your connections are correct for
each channel, trim the lengths to keep them short. Avoid cutting leads
too short.

7. At the source-end of cables from voltage devices:

- remove the drain wire and foil shield

- apply shrink wrap as an option

14 ControlLogix™ Analog HART Modules

- connect to devices keeping the leads short

Important: If noise persists, try grounding the opposite end of the cable,
instead (Ground one end only.)

Terminal Block Layout

The following figure shows the general terminal block layout. The input
signal type will determine which pins are used.

IN0+

IN0-

IN1+

IN1-

RTN

IN2+

IN2-

IN3+

IN3-

IN4+

IN4-

IN5+

IN5-

RTN

IN6+

IN6-

IN7+

IN7-

2

1

4

6

8

10

12

14

16

18

20

22

24

26

28

30

32

34

36

I RTN-0

3

NC

5

I RTN-1

7

NC

9

RTN

11

I RTN-2

13

NC

15

I RTN-3

17

NC

I RTN-4

19

NC

21

23

I RTN-5

NC

25

RTN

27

29

I RTN-6

31

NC

I RTN-7

33

NC

35

VOUT-4

IOUT-4

RTN

VOUT-5

IOUT-5

VOUT-6

IOUT-6

RTN

VOUT-7

IOUT-7

1

2

4

6

8

10

12

14

16

18

20

VOUT-0

3

IOUT-0

5

RTN

7

VOUT-1

9

IOUT-1

11

VOUT-2

13

IOUT-2

15

RTN

17

VOUT-3

19

IOUT-3

Wiring Inputs to the
IF8H Module

Voltage Inputs - Voltage inputs use the terminal block pins labelled IN+#
and IN-#.

Voltage Input

+V

- V

IN0+

IN0-

IN1+

IN1-

RTN

IN2+

IN2-

IN3+

IN3-

IN4+

IN4-

IN5+

IN5-

RTN

IN6+

IN6-

IN7+

IN7-

1

2

4

6

8

10

12

14

16

18

20

22

24

26

28

30

32

34

36

I RTN-0

3

NC

5

I RTN-1

7

NC

RTN

9

11

I RTN-2

13

NC

15

I RTN-3

17

NC

19

I RTN-4

21

NC

23

I RTN-5

25

NC

27

RTN

29

I RTN-6

31

NC

33

I RTN-7

35

NC

Note: All terminals marked RTN are connected internally.

Chapter 2: Installing And Wiring Your Module 15

Current Inputs - Current inputs use the terminal block pins labelled IN+#,
IN-#, and I RTN-#. Note that HART communication is only active with
current inputs.

2 Wire Current Input

2 Wire
XMTR

+ -

+

24V DC
Power
Supply

-

4 Wire Current Input

+

+

24V D C

4 Wire

Power

XMTR

Supply

-

--

IN0+

IN0-

IN1+

IN1-

RTN

+

IN2+

IN2-

IN3+

IN3-

IN4+

IN4-

IN5+

IN5-

RTN

IN6+

IN6-

IN7+

IN7-

1

2

I RTN-0

3

4

NC

5

6

I RTN-1

7

8

NC

9

10

12

14

16

18

20

22

24

26

28

30

32

34

36

RTN

11

I RTN-2

13

NC

15

I RTN-3

17

NC

19

I RTN-4

21

NC

23

I RTN-5

25

NC

27

RTN

29

I RTN-6

31

NC

33

I RTN-7

35

NC

Note: All terminal s ma rked RTN are connected internally.

Note: When using current inputs, if multiple (-) terminals are connected
together, the channel to channel isolation will be compromised (i.e. this
would be considered a single ended wiring configuration). If a single
ended wiring configuration is to be utilized, the (-) terminals should also
be connected to the RTN to maintain module accuracy.

Differential Current
Channel Terminals Channel Terminals

Channel 0 IN0+, IN0-, iRTN0 Channel 4 IN4+, IN4-, iRTN4
Channel 1 IN1+, IN1-, iRTN1 Channel 5 IN5+, IN5-, iRTN5
Channel 2 IN2+, IN2-, iRTN2 Channel 6 IN6+, IN6-, iRTN6
Channel 3 IN3+, IN3-, iRTN3 Channel 7 IN7+, IN7-, iRTN7

Differential Voltage

Channel Terminals Channel Terminals

Channel 0 IN0+, IN0- Channel 4 IN4+, IN4­Channel 1 IN1+, IN1- Channel 5 IN5+, IN5­Channel 2 IN2+, IN2- Channel 6 IN6+, IN6­Channel 3 IN3+, IN3- Channel 7 IN7+, IN7-

16 ControlLogix™ Analog HART Modules

Wiring Outputs to the
OF8H Module

The OF8H module supports voltage and current outputs.

Voltage Outputs - Voltage outputs use the terminal block pins labelled
VOUT-# and RTN

Current Outputs - Current outputs use the terminal block pins labelled
IOUT-# and RTN

Note: HART communication is only active with current outputs.

Chapter 2: Installing And Wiring Your Module 17

This page intensionally left blank.

18 ControlLogix™ Analog HART Modules

Ownership and
Connections

Chapter 3Chapter 3

Chapter 3

Chapter 3Chapter 3

Operation Within the
ControlLogix System

This chapter describes how the 1756sc-IF8H and 1756sc-OF8H analog
HART modules work within the ControlLogix system. This chapter
covers:

• Ownership and connections to the module

• Direct connections

• Listen only mode

• Configuration changes with multiple owners.

Every I/O module in the ControlLogix system must be owned by a
Logix5550 Controller to be useful. This owner-controller stores
configuration data for every module that it owns and can be local or
remote in regard to the I/O module’s position. The owner sends the I/O
module configuration data to define the module’s behavior and begin
operation within the control system. Each ControlLogix I/O module
must continuously maintain communication with its owner to operate
normally.

Using RSNetWorx
and RSLogix 5000

Typically, each module in the system will have only 1 owner. Input
modules can have more than 1 owner. Output modules, however, are
limited to a single owner.

The I/O configuration portion of RSLogix5000 generates the
configuration data for each I/O module in the control system, whether
the module is located in a local or remote chassis. A remote chassis,
also known as networked, contains the I/O module but not the
module’s owner controller. Configuration data is transferred to the
controller during the program download and subsequently transferred
to the appropriate I/O modules. I/O modules in the same chassis as the
controller are ready to run as soon as the configuration data has been
downloaded. You must run RSNetWorx to enable I/O modules in the
networked chassis.

Running RSNetWorx transfers configuration data to networked modules
and establishes a Network Update Time (NUT) for ControlNet that is
compliant with the desired communications options specified for each
module during configuration. If you are not using I/O modules in a
networked chassis, running RSNetWorx is not necessary. However,
anytime a controller references an I/O module in a networked chassis,

RSNetWorx must be run to configure ControlNet. Follow these general
guidelines when configuring I/O modules:

1. Configure all I/O modules for a given controller using RSLogix 5000

and download that information to the controller.

2. If the I/O configuration data references a module in a remote chassis,

run RSNetWorx.

Important: RSNetWorx must be run whenever a new module is added
to a networked chassis. When a module is permanently removed from a
remote chassis, we recommend that RSNetWorx be run to optimize the
allocation of network bandwidth.

Direct Connections

Module Operation

A direct connection is a real-time data transfer link between the
controller and the device that occupies the slot that the configuration
data references. When module configuration data is downloaded to an
owner-controller, the controller attempts to establish a direct
connection to each of the modules referenced by the data.

If a controller has configuration data referencing a slot in the control
system, the controller periodically checks for the presence of a device
there. When a device’s presence is detected, the controller
automatically sends the configuration data. If the data is appropriate to
the module found in the slot, a connection is made and operation
begins. If the configuration data is not appropriate, the data is rejected
and an error message displays in the software. In this case, the
configuration data can be inappropriate for any of a number of
reasons.

The controller maintains and monitors its connection with a module.
Any break in the connection, such as removal of the module from the
chassis while under power, causes the controller to set fault status bits
in the data area associated with the module. The RSLogix 5000
software may monitor this data area to announce the modules’ failures.

In traditional I/O systems, controllers poll input modules to obtain
their input status. Analog input modules in the ControlLogix system
are not polled by a controller once a connection is established. The
modules multicast their data periodically. Multicast frequency depends
on the options chosen during configuration and where in the control
system that input module physically resides. An input module’s
communication, or multicasting, behavior varies depending upon
whether it operates in the local chassis or in a remote chassis. The
following sections detail the differences in data transfers between
these set-ups.

Modules in a Local
Chassis

Chapter 3: Operation within the System 21

When a module resides in the same chassis as the owner controller, the
following two configuration parameters will affect how and when the
input module multicasts data:

· Real Time Sample (RTS) configured via Real Time Sample tag.

· Requested Packet Interval (RPI) configured via I/O module properties.

Real Time Sample (RTS)

This configurable parameter instructs the module to perform the
following operations:

1. scan all of its input channels and store the data into on-board

memory

2. multicast the updated channel data (as well as other status data) to

the backplane of the local chassis

Requested Packet
Interval (RPI)

This configurable parameter also instructs the module to multicast its
channel and status data to the local chassis backplane.

The RPI instructs the module to multicast the current contents of its
on-board memory when the RPI expires, (i.e. the module does not
update its channels prior to the multicast).

Important: The RPI value is set during the initial module
configuration using RSLogix 5000.

It is important to note that the module will reset the RPI timer each
time an RTS is performed. This operation dictates how and when the
owner controller in the local chassis will receive updated channel data,
depending on the values given to these parameters. If the RTS value is
less than or equal to the RPI, each multicast of data from the module
will have updated channel information. In effect, the module is only
multicasting at the RTS rate.

If the RTS value is greater than the RPI, the module will multicast at
both the RTS rate and the RPI rate. Their respective values will dictate
how often the owner controller will receive data and how many
multicasts from the module contain updated channel data. Note: Even
though data may be transferred at the RPI rate, the data will be
identical to the previous RTS data transfer. HART data can change.
Setting the RPI < 100 msec will allow you to see all changes.

22 ControlLogix™ Analog HART Modules

Modules in a Remote
Chassis

If an input module resides in a networked chassis, the role of the RPI
and the module’s RTS behavior change slightly with respect to getting
data to the owner. The RPI and RTS intervals still define when the
module will multicast data within its own chassis (as described in the
previous section), but only the value of the RPI determines how often
the owner controller will receive it over the network.

When an RPI value is specified for an input module in a remote chassis,
in addition to instructing the module to multicast data within its own
chassis, the RPI also “reserves” a spot in the stream of data flowing
across the ControlNet network.

The timing of this “reserved” spot may or may not coincide with the
exact value of the RPI, but the control system will guarantee that the
owner controller will receive data at least as often as the specified
RPI.

The “reserved” spot on the network and the module’s RTS are
asynchronous to each other. This means there are Best and Worst Case
scenarios as to when the owner controller will receive updated channel
data from the module in a networked chassis.

Listen-Only Mode

Best Case RTS Scenario

In the Best Case scenario, the module performs an RTS multicast with
updated channel data just before the “reserved” network slot is made
available. In this case, the remotely located owner receives the data
almost immediately.

Worst Case RTS Scenario

In the Worst Case scenario, the module performs an RTS multicast just
after the “reserved” network slot has passed. In this case, the owner­controller will not receive data until the next scheduled network slot.

Because it is the RPI and NOT the RTS which dictates when the
module’s data will be sent over the network, we recommend the RPI
value be set LESS THAN OR EQUAL TO the RTS to make sure that
updated channel data is received by the owner controller with each
receipt of data.

Any controller in the system can listen to the data from any I/O
module (e.g. input data or “echoed” output data) even if the controller
does not own the module (i.e. it does not have to hold the module’s
configuration data to listen to the module).

The “listen only” mode is set during the I/O configuration process.

Choosing a ‘Listen-Only’ mode option allows the controller and
module to establish communications without the controller sending

Multiple Owners of
Input Modules

Chapter 3: Operation within the System 23

any configuration data. In this instance, another controller owns the
module being listened to.

Important: Controllers using the Listen-Only mode continue to receive
data multicast from the I/O module as long as a connection between an
owner and I/O module is maintained. If the connection between all
owners and the module is broken, the module stops multicasting data and
connections to all ‘Listening controllers’ are also broken.

Because ‘Listening controllers’ lose their connections to modules
when communications with the owner stop, the ControlLogix system
will allow you to define more than one owner for input modules.

Important: Only input modules can have multiple owners. If multiple
owners are connected to the same input module, they must maintain
identical configuration for that module.

In the example below, Controller A and Controller B have both been
configured to be the owner of the input module.

When the controllers begin downloading configuration data, both try
to establish a connection with the input module. Whichever
controller’s data arrives first establishes a connection. When the
second controller’s data arrives, the module compares it to its current
configuration data (the data received and accepted from the first
controller).

If the configuration data sent by the second controller matches the
configuration data sent by the first controller the connection is also
accepted. If any parameter of the second configuration data is different
from the first, the module rejects the connection and the user is
informed by an error in the software.

The advantage of multiple owners over a ‘Listen-only’ connection is
that now either of the controllers can lose the connection to the module
and the module will continue to operate and multicast data to the
system because of the connection maintained by the other owner
controller.

Note: The previous discussion of multiple owners assumes the
configuration tag “.configrevnumber” is set to 1. Operation differs is
the tag is set to 0. Refer to Chapter 5 for descriptions of this tag’s
settings.

24 ControlLogix™ Analog HART Modules

Configuration
Changes in an Input
Module with Multiple
Owners

You must be careful when changing an input module’s configuration data
in a multiple owner scenario. When the configuration data is changed in
one of the owners, for example, Controller A, and sent to the module,
that configuration data is accepted as the new configuration for the
module. Controller B will continue to listen, unaware that any changes
have been made in the module’s behavior.

Important: When changing configuration for a module with multiple
owners, we recommend the connection be inhibited. To prevent other
owners from receiving potentially erroneous data, as described above,
the following steps must be followed when changing a module’s
configuration in a multiple owner scenario when on-line:

1. For each owner controller, inhibit the controller’s connection to the
module in the software on the I/O Module Connection tab.

2. Make the appropriate configuration data changes in the software.

3. Repeat steps 1 and 2 for all owner controllers, making the exact
same changes in all controllers.

4. Uncheck the Inhibit box in each owner’s configuration to reconnect

each module.

Chapter 4

Configuring RSLogix 5000 For The IF8H
and OF8H

This chapter explains how to incorporate your module into the
ControlLogix system. It also covers a brief overview of the configuration,
input and output (OF8H only) tags Topics discussed include:

• Adding your module to a RSLogix 5000 project

• Configuration tags overview

• Input tags overview

• Output tags overview

Module Installation

Adding Your Module
to a Project

The process of incorporating your HART module into the ControlLogix
system is similar to the process needed to add an Allen-Bradley module.
You will use your RSLogix 5000 programming software to install and
configure your HART module. The module is not currently in the
RSLogix 5000 I/O pick list, so you will need to copy and paste information
from a sample project that can be obtained from our website at
(www.spectrumcontrols.com). You may also choose to build onto the
sample project itself. The sample project contains the module profile,
configuration tags, input tags, and ladder samples needed to configure
each HART module.

The module has a unique set of tag definitions which are used to configure
specific features. Chapter 5 and 6, Channel Configuration, Data, and
Status, gives you detailed information about available configuration settings
and status information. These values are set using your programming

26 ControlLogix™ Analog HART Modules

software and ladder logic. Before you can use these features you must
first include the module into the project.

1.

Download and open the sample project from our website at
www.spectrumcontrols.com It contains information for the IF8H and
OF8H. Open your project. Drag and drop the IF8H or OF8H module into
the I/O configuration section of your project.

a) Open the sample project.

b) Open your new project.

c) Click once on the IF8H or OF8H in the IO configurator.

d) Drag and drop it into the I/O Configurator section of your project.

Note: You may need to change the slot number of the module after
pasting it into your project.

Note: If only one of the HART modules is to be utilized, copy the profile,
tags and ladder for that module only.

Chapter 4: Programming Your Module 27

See Appendix C for more details regarding module profile settings.

2.

Drag and drop the IF8H or OF8H user-defined data types from the
sample project into your project.

There are eleven user defined data types that need to be moved.

•

GetDeviceInfo

•

If8hConfigurationBlock

•

Of8hConfigurationBlock

•

If8hInputBlock

•

Of8hInputBlock

•

Of8hOutputBlock

•

Packet0

•

Packet1

•

Packet2

•

Packet3

•

Packet4

28 ControlLogix™ Analog HART Modules

a) Click on the data type

b) Drag it into your new project.

c) Continue to drag and drop the data types until all have been moved.

Note: These can only be moved one at a time.

3.

Drag and drop the controller tags from the sample project into your
project.

a) Right click on the Controller Tags item of the sample project and select

edit.

b) Right click on the Controller Tags item of your project and select edit.

c) Scroll down to the Controller tags of the sample project and select all

the tags by highlighting them. Be sure to select the tags by using the
gray buttons to the left of the tag name. See figure below.

Chapter 4: Programming Your Module 29

d) Paste the tags into your project. Be sure to paste the tags in the empty

field marked with an asterisk. Refer to the figure above.

Note: If you are sending HART messages to the module, you will need
to copy the If8h0Messaging program and or the Of8h0Messaging
program. You will also need to copy the associated program tags for each
routine. Use the procedure in step 3 for copying the program tags to your
project.

Note: If8h0Configuration / If8h0Input and Of8h0Configuration /
Of8h0Input contain the configuration, data and status tags for the modules.
The other tags are used for performing various functions to your module
via ladder logic.

Note: Certain tag names include a zero succeeding the catalog number;
for example, If8h0Configuration contains a zero. The zero is used to
identify the module if there’s more than one IF8H module in the system.
This number could also be used to imply the slot number of the module.
The user can omit this number or change the tag name if need be.

Note: Be sure all tags are displayed before moving them. Select Display
All from the Edit drop down window.

30 ControlLogix™ Analog HART Modules

Note: The “Local:e:I” and “Local:e:C” tags are not copied.

4.

Create a new ladder logic routine in your project.

a) In your project, double click on the MainRoutine.

b) Double click on the MainRoutine item in the sample project to display

the ladder logic.

c) Left mouse inside the MainProgram ladder logic in the sample project

and press crtl-A to select all the rungs.

d) Drag and drop these rungs over and add them to the MainRoutine in

your project.

Note: You will need to delete the one blank “solid bar” rung either at the
top or bottom of the routine which was left over when you double clicked
on the empty MainRoutine in your project.

Configuration Tags
Overview

Chapter 4: Programming Your Module 31

e) Drag and drop the routines IF8H0_Packet_Data and

OF8H0_Packet_Data to the MainProgram in your project.

Note: You may choose to omit pasting the OF8H0_Packet_Data routine
if you are not using the OF8H module in your system.

f) Now add JSR ladder instructions in your MainRountine which calls the

two routines in step e.

Note: RSLogix 5000 will verify the ladder logic sample. You may receive
errors regarding invalid tags. You will need to change the slot addressing
in the logic to coordinate with the location of the module.

This completes the installation of the module in the system

The configuration tags for the IF8H and OF8H that were copied in step 3
are used to change the operation settings, including input type, filter­frequency, scaling, etc. The data contained in these tags are then copied
to both the IF8H and OF8H local configuration tags by the ladder in step

4. When using generic profiles, the local module tags that are created are
made up of a single dimensional array with only one data type allowed,
usually a DINT. Therefore, the process of copying the defined
configuration tags to the local configuration tags is required in order to
parse the data. Specific information regarding tag settings may be found
in Chapter 5.

Note: The local configuration tags (i.e Local:e:C) mentioned above are
automatically created when the module was copied from the sample
project in step 1.

Note: The defined configuration tags (If8h0Configuration) are copied to
the local configuration tags (Local:e:C) by the ladder in step 4.

32 ControlLogix™ Analog HART Modules

1756sc-IF8H (If8h0Configuration)

Chapter 4: Programming Your Module 33

1756sc-OF8H (Of8h0Configuration)

34 ControlLogix™ Analog HART Modules

Input Tags Overview

The input tags contain the analog data, status, and HART data. As in the
case of the configuration tags, the input tags are also copied to the local
input tags for the module. For details regarding the analog data and status
refer to Chapter 5. For details regarding the HART data refer to Chapter

7.

Note: The local input tags (i.e. Local:e:I) mentioned above are
automatically created when the module was copied from the sample
project in step 1.

Note: The defined configuration tags (If8h0Input) are copied to the local
input tags (Local:e:I) by the ladder in step 4.

Note: The HART data found in the input tags has not been demultiplexed.
In other words, the data is changing dynamically depending on what
channel and which HART packet is currently being scanned. Please refer
to chapter 7 for more details regarding demultiplexing of the HART data.

1756sc-IF8H (If8h0Input)

Chapter 4: Programming Your Module 35

1756sc-OF8H (Of8hInput)

Output Tags
Overview
(OF8H Only)

The output tags are used to control the output voltage or current level,
depending on the configuration settings, of each individual channel.

Note: The local output tags (i.e. Local:e:O) are automatically created
when the module was copied from the sample project in step 1.

Note: The defined output tags (Of8h0Output) are copied to the local
output tags (Local:e:O) by the ladder in step 4.

36 ControlLogix™ Analog HART Modules

Chapter 5: 1756sc-IF8H Channel Configuration, Data, and Status 37

Configuration, Data,Configuration, Data,

Configuration, Data,

Configuration, Data,Configuration, Data,

Chapter 5

and Staand Sta

and Sta

and Staand Sta
for the 1756sc-IF8Hfor the 1756sc-IF8H

for the 1756sc-IF8H

for the 1756sc-IF8Hfor the 1756sc-IF8H

Read this chapter to:

•

Send configuration data to the module

• Configuration tags

•

Module filter selection

• Module input tags

• Accessing the module tags

•

Changing configuration information at the tags

This chapter outlines the detailed settings for the 1756sc-IF8H. These
settings determine the modules input types, filter frequencies, scan rates,
and various attributes. Detailed descriptions of these settings are available
in the Tag Definition section of this chapter.

tus tus

tus

tus tus

TT

T

TT

aa

a

aa

gsgs

gs

gsgs

SendSend

Send

SendSend
ConfigurationConfiguration

Configuration

ConfigurationConfiguration
Data to theData to the

Data to the

Data to theData to the
ModuleModule

Module

ModuleModule

Note: The following format is used to describe tags

Tag Name Data Type Style Description

After changing the configuration tags in this chapter you must then send
them to the module. To do this you may perform any of these operations:

1. Inhibit then un-inhibit the module via the module properties dialog,
Connection Tab

2. Reset the module via the modules properties dialog. Module Info tab.

3. Reset the module via ladder logic. See the “DoReset” rung in the
sample ladder located in Chapter 8.

4. Perform a “Set Attribute All” or Module Reconfigure message
instruction via ladder logic. Refer to Chapter 8 for information about the
“DoSetAttrAll” command.

Note: If an invalid configuration is sent to the module a connection error
will occur. See chapter 9 for a list of error codes.

38 ControlLogix™ Analog HART Modules

ConfigurationConfiguration

Configuration

ConfigurationConfiguration
TT

aa

gs fgs f

T

a

gs f

TT

aa

gs fgs f

1756sc-IF8H1756sc-IF8H

1756sc-IF8H

1756sc-IF8H1756sc-IF8H

or theor the

or the

or theor the

The following tags allow for custom configuration of the module. These
tags can be found within the controller scope under the tag name
If8h0Configuration.

Tag Name Data Type Style Description

If8h0Configuration If8hConfigurationBlock NA Module configuration
If8h0Configuration.ConfigRevision SINT DEC Controls mult iple owner connections.

If8h0Configuration.AdcFilter SINT DEC 0 = 10Hz 4 = 250Hz

If8h0Configuration.RTS INT DEC The time in millis econds that updated

1

If8h0Configuration.ChXConfigBits
If8h0Configuration.ChXConfigBits.0

If8h0Configuration.ChXConfigBits.1

If8h0Configuration.ChXConfigBits.2

If8h0Configuration.ChXConfigBits.3

If8h0Configuration.ChXConfigBits.4

If8h0Configuration.ChXConfigBits.5

If8h0Configuration.ChXConfigBits.6

If8h0Configuration.ChXConfigBits.7

1

X repres ents the module channel number (0 to 7).

SINT BIN Channel c onfiguration settings

1

BOOL DEC Unused

1

BOOL DEC Unused

1

BOOL DEC Unused

1

BOOL DEC Unused

1

BOOL DEC Enables lat ching for the rate alarm.

1

BOOL DEC Enables latching for all four process

1

BOOL DEC Disable alarms

1

BOOL DEC Enable HART Communication

Table 5.1a

0 = Always connect, overwrite w/new
configuration.
1 = Only connect if configuration
matches existing configuration.

1 = 50Hz 5 = 1000Hz
2 = 60Hz 6 = 20Hz
3 = 100Hz 7 = 15Hz

input data is to be sent from the
module to the controller.
18 to 10000 msec

Set to zero

Set to zero

Set to zero

Set to zero

Latching causes the rate alarm to
remain set until an unlatch service is
explic itly sent to the channel or
alarm.
0 = Rate alarm unlatched
1 = Rate alarm latched

alarms: low, low low, high, high high.
Latching causes the process alarm to
remain set until an unlatch service is
explic itly sent to the channel or
alarm.
0 = Alarms unlatched
1 = Alarms lat ched

0 = Enabled
1 = Di sabled

0 = Di sabled
1 = Enabled

Chapter 5: 1756sc-IF8H Channel Configuration, Data, and Status 39

Table 5.1b

Tag Name Data Type Style Description

1

If8h0Configuration.ChXInputRange

SINT DEC Configures the channel's input range.

Input ranges include:
0 = -10.25 to 10.25V
1 = 0 to 5.125V
2 = 0 to 10.25V
3 = 0 to 20.58 mA
4 = 3.42 mA to 20.58 mA

1

If8h0Configuration.ChXDigitalFilter

INT DEC A non-zero value enables the filter,

providing a time constant in
milliseconds used in a first order lag
filter to smooth the input signal. If non­zero, must be greater than twice the
RTS rate.
0 to 20100 msec

1

If8h0Configuration.ChXRateAlarmLimit

REAL FLOAT The trigger point for the rate alarm

status bit which will set if the input
signal changes at a rate faster than the
configured rate alarm. Configured in
user sc aling units per second.

If8h0Configuration.ChXLowSignal

1

REAL FLOAT One of four points used in scaling. The

low signal represents the minimum
input range.

If8h0Configuration.ChXHighSignal

1

REAL FLOAT One of four points used in scaling. The

high signal represents the maximum
input range.

1

If8h0Configuration.ChXLowEngineering

REAL FLOAT One of four points used in scaling. The

low engineering represents the
minimum sc aled range.

1

If8h0Configuration.ChXHighEngineering

REAL FLOAT One of four points used in scaling. The

high engineering represents the
maximum scaled range.

If8h0Configuration.ChXLowAlarm

1

REAL FLOAT The low process alarm trigger point.

Enter the value in terms of engineering
units.

If8h0Configuration.ChXHighAlarm

1

REAL FLOAT The high process alarm trigger point.

Enter the value in terms of engineering
units.

1

If8h0Configuration.ChXLowLowAlarm

REAL FLOAT The low low process alarm trigger point.

Enter the value in terms of engineering
units.

1

X represents the module channel number (0 to 7).

40 ControlLogix™ Analog HART Modules

Table 5.1c

Tag Name Data Type Style Description

If8h0Configuration.ChXHighHighAlarm

1

REAL FLOAT The high high process alarm trigger

point. Enter the value in terms of
engineering units.

If8h0Configuration.ChXAlarmDeadband

1

REAL FLOAT Forms a deadband around the process

alarms which causes the
corresponding process alarm status
bit to remain set until the input moves
beyond the trigger point by greater
than the amount of the alarm
deadband.

If8h0Configuration.ChXCalBias

1

REAL FLOAT

Offset to add to channel analog value

If8h0Configuration.HandleTimeout INT DEC There is a handle timeout associat ed

with the final reply message. After the
module obtaines the requested
information from the HART devic e, it
will start the HandleTimeout timer
(duration defined by the
HandleTimeout tag). The replay
message will be kept in memory
during the HandleTimeout period.
After the timeout occurs or after the
message is retrieved by the pass­through response query command, the
storage buffer will be discarded, and
another pass through message will be
serviced without being rejected.
HandleTimeout is in the range of 1 to

255 seconds .
If8h0Configuration.ModuleConfigBits INT BIN Module function settings
If8h0Configuration.ModuleConfigBits.0 BOOL DEC Reserved set to zero
If8h0Configuration.ModuleConfigBits.1 BOOL DEC Reserved set to zero
If8h0Configuration.ModuleConfigBits.2 BOOL DEC Reserved set to zero
If8h0Configuration.ModuleConfigBits.3 BOOL DEC Reserved set to zero
If8h0Configuration.ModuleConfigBits.4 BOOL DEC Reserved set to zero
If8h0Configuration.ModuleConfigBits.5 BOOL DEC Reserved set to zero
If8h0Configuration.ModuleConfigBits.6 BOOL DEC Reserved set to zero
If8h0Configuration.ModuleConfigBits.7 BOOL DEC Reserved set to zero
If8h0Configuration.ModuleConfigBits.8 BOOL DEC Reserved set to zero
If8h0Configuration.ModuleConfigBits.9 BOOL DEC Reserved set to zero
If8h0Configuration.ModuleConfigBits.10 BOOL DEC Reserved set to zero
If8h0Configuration.ModuleConfigBits.11 BOOL DEC Reserved set to zero
If8h0Configuration.ModuleConfigBits.12 BOOL DEC Reserved set to zero
If8h0Configuration.ModuleConfigBits.13 BOOL DEC Reserved set to zero

1

X represents the module channel number (0 to 7).

Chapter 5: 1756sc-IF8H Channel Configuration, Data, and Status 41

Table 5.1d

Tag Name Data Type Style Description

If8h0Configuration.ModuleConfigBits.14

If8h0Configuration.ModuleConfigBits.15

2

The configuration of bits 14 and 15 directly eff ect the update time of the HART data acquisition for the module, f or example if

bit 15 is set, the HART update time for each channel w ill be doubled.

2

2

BOOL DEC Bits 14 and 15 determine how often

the pass-through command is serviced

by the module.

15,14 = 00 = pass-through serviced

once per two channels scanned

15,14 = 01 = pass-through serviced

once per module scan

15,14 = 1X = pass-through serviced

once per channel scan

BOOL DEC Bits 14 and 15 determine how often

the pass-through command is serviced

by the module.

15,14 = 00 = pass-through serviced

once per two channels scanned

15,14 = 01 = pass-through serviced

once per module scan

15,14 = 1X = pass-through serviced

once per channel scan

Module FilterModule Filter

Module Filter

Module FilterModule Filter
SelectionSelection

Selection

SelectionSelection

Module Update TimeModule Update Time

Module Update Time

Module Update TimeModule Update Time

The module update time is defined as the time required for the module to
sample and convert the input signals of all enabled input channels and
make the resulting data values available to the processor. The update time
is influenced by the input type and filter frequency configuration settings.
The following table shows associated time adders based on frequency
selection.

Filter Update Time

10Hz 61 m s per channel
15Hz 41 m s per channel
20Hz 31 m s per channel
50Hz 11 m s per channel
60Hz 11 m s per channel
100Hz 7 ms per channel
250Hz 3.5 ms per channel
1000Hz 2.25 ms per channel

ADC FilterADC Filter

ADC Filter

ADC FilterADC Filter

::

:

::

The module uses a ADC filter that provides high frequency noise rejection
for the input signals. The ADC filter is programmable, allowing you to
select from eight filter frequencies for each channel.

42 ControlLogix™ Analog HART Modules

Selecting a low value (i.e. 10 Hz) for the filter frequency provides the best
noise rejection for a channel, but it also increases the channel update time.
Selecting a high value for the filter frequency provides lower noise
rejection, but decreases the channel update time.

The module filter is a built-in feature of the Analog-to-Digital convertor
which attenuates the input signal beginning at the specified frequency.

In addition to frequency rejection, a by-product of the filter selection is the
minimum sample rate (RTS) that is available. For example, the 1000Hz
selection will not attenuate any frequencies less than 1000Hz and will
allow sampling of all 8 channels within 18ms. But the 10Hz selection will
reject all frequencies above 10Hz and will only allow sampling all 8
channels within 488ms. Table 5.2 lists the minimum RTS rate associated
with each ADC filter setting. Refer to table 5.1a to configure this
feature.

Table 5.2

ADC Filte r (Hz) Mi nimum RTS (ms)

10 488
15 328
20 248
50 88

60 88
100 56
250 28

1000 18

Digital FilterDigital Filter

Digital Filter

Digital FilterDigital Filter

The digital filter smooths input data noise transients on each input channel.
This value specifies the time constant for a digital first order lag filter on
the input. It is specified in units of milliseconds. A value of 0 disables the
filter.

The digital filter equation is a classic first order lag equation.

Yn = Yprevn + (dT/(dT + TA) * (Xn – Yprevn))

Yn = Filtered peak voltage (PV)

Yprevn = Previous Yn

dT = Time expired since previous Yn (Seconds)

Unfiltered
TA = 0.01 Sec
TA = 0.50 Sec
TA = 0.99 Sec

Chapter 5: 1756sc-IF8H Channel Configuration, Data, and Status 43

TA = User specified digital filter time constant (Seconds)

Xn = Current value, unfiltered peak voltage (PV)

Using a step input change to illustrate the filter response, as shown below,
you can see that when the digital filter time constant elapses, 63.2% of the
total response is reached, each additional time constant achieves 63.2% of
the remaining response.

Amplitude

(Not to scale)

63%

0.0

0.5

0.01 0.99

Time

44 ControlLogix™ Analog HART Modules

Input Input

Input

Input Input

TT

T

TT

aa

a

aa

gsgs

gs

gsgs

The following fault and status reporting and module data sections allow
monitoring of faults, status, and input data from the module. These tags
can be found within the If8h0Input controller tag.

Table 5.3a

Tag Name Data Type Style Description

If8h0Input If8h0InputBlock NA Module input data
If8h0Input.ModuleStatus DINT BIN General module status
If8h0Input.ModuleStatus.0 BOOL DEC Channel 0 general fault status

0 = No fault
1 = Fault

If8h0Input.ModuleStatus.1 BOOL DEC Channel 1 general fault status

0 = No fault
1 = Fault

If8h0Input.ModuleStatus.2 BOOL DEC Channel 2 general fault status

0 = No fault
1 = Fault

If8h0Input.ModuleStatus.3 BOOL DEC Channel 3 general fault status

0 = No fault
1 = Fault

If8h0Input.ModuleStatus.4 BOOL DEC Channel 4 general fault status

0 = No fault
1 = Fault

If8h0Input.ModuleStatus.5 BOOL DEC Channel 5 general fault status

0 = No fault
1 = Fault

If8h0Input.ModuleStatus.6 BOOL DEC Channel 6 general fault status

0 = No fault
1 = Fault

If8h0Input.ModuleStatus.7 BOOL DEC Channel 7 general fault status

0 = No fault
1 = Fault

If8h0Input.ModuleStatus.8 BOOL DEC Channel 0 broken wire

0 = Connection
1 = Open circuit

If8h0Input.ModuleStatus.9 BOOL DEC Channel 1 broken wire

0 = Connection
1 = Open circuit

If8h0Input.ModuleStatus.10 BOOL DEC Channel 2 broken wire

0 = Connection
1 = Open circuit

If8h0Input.ModuleStatus.11 BOOL DEC Channel 3 broken wire

0 = Connection
1 = Open circuit

If8h0Input.ModuleStatus.12 BOOL DEC Channel 4 broken wire

0 = Connection
1 = Open circuit

Chapter 5: 1756sc-IF8H Channel Configuration, Data, and Status 45

Table 5.3b

Tag Name Data Type Style Description

If8h0Input.ModuleStatus.13 BOOL DEC Channel 5 broken wire

0 = Connection
1 = Open circuit

If8h0Input.ModuleStatus.14 BOOL DEC Channel 6 broken wire

0 = Connection
1 = Open circuit

If8h0Input.ModuleStatus.15 BOOL DEC Channel 7 broken wire

0 = Connection
1 = Open circuit

If8h0Input.ModuleStatus.16 BOOL DEC Channel 0 HART out-of-service

0 = In service
1 = Out-of-service

If8h0Input.ModuleStatus.17 BOOL DEC Channel 1 HART out-of-service

0 = In service
1 = Out-of-service

If8h0Input.ModuleStatus.18 BOOL DEC Channel 2 HART out-of-service

0 = In service
1 = Out-of-service

If8h0Input.ModuleStatus.19 BOOL DEC Channel 3 HART out-of-service

0 = In service
1 = Out-of-service

If8h0Input.ModuleStatus.20 BOOL DEC Channel 4 HART out-of-service

0 = In service
1 = Out-of-service

If8h0Input.ModuleStatus.21 BOOL DEC Channel 5 HART out-of-service

0 = In service
1 = Out-of-service

If8h0Input.ModuleStatus.22 BOOL DEC Channel 6 HART out-of-service

0 = In service
1 = Out-of-service

If8h0Input.ModuleStatus.23 BOOL DEC Channel 7 HART out-of-service

0 = In service

1 = Out-of-service
If8h0Input.ModuleStatus.24 BOOL DEC Unused
If8h0Input.ModuleStatus.25 BOOL DEC Calibration fault

0 = No fault

1 = Fault
If8h0Input.ModuleStatus.26 BOOL DEC Calibration in progress

0 = Calibration NOT active

1 = Calibrating
If8h0Input.ModuleStatus.27 BOOL DEC Unused
If8h0Input.ModuleStatus.28 BOOL DEC Unused
If8h0Input.ModuleStatus.29 BOOL DEC Unused
If8h0Input.ModuleStatus.30 BOOL DEC Unused
If8h0Input.ModuleStatus.31 BOOL DEC Analog group fault

0 = No fault

1 = Fault

46 ControlLogix™ Analog HART Modules

Tag Name Data Type Style Description

If8h0Input.ChanStatus SINT[8] BIN An array of 8 SINT which display

If8h0Input.ChanStatus[X]

1

If8h0Input.ChanStatus[X].0

If8h0Input.ChanStatus[X].1

If8h0Input.ChanStatus[X].2

If8h0Input.ChanStatus[X].3

If8h0Input.ChanStatus[X].4

If8h0Input.ChanStatus[X].5

If8h0Input.ChanStatus[X].6

If8h0Input.ChanStatus[X].7

SINT BIN General channel status byte

1

BOOL DEC User value exceeded high high limit.

1

BOOL DEC User value exceeded low low limit.

1

BOOL DEC User value exceeded high limit.

1

BOOL DEC User value exceeded low limit.

1

BOOL DEC Specified ramp rate exceeded.

1

BOOL DEC Over Range alarm

1

BOOL DEC Under Range alarm

1

BOOL DEC Channel calibration fault

If8h0Input.ChanData REAL[8] FLOAT An array of 8 floating point registers

If8h0Input.ChanData[X]

1

X represents the module channel number (0 to 7).

1

REAL FLOAT Channel analog data in engineering

Table 5.3c

general status for each channel.

0 = No alarm
1 = Alarm

0 = No alarm
1 = Alarm

0 = No alarm
1 = Alarm

0 = No alarm
1 = Alarm

0 = No alarm
1 = Alarm

0 = No alarm
1 = Alarm

0 = No alarm
1 = Alarm

0 = No fault
1 = Fault

which dis play the analog data for
each channel in engineering units.

units

Chapter 5: 1756sc-IF8H Channel Configuration, Data, and Status 47

Table 5.3d

Tag Name Data Type Style Description

If8h0Input.CST DINT[2] DEC This is the times tamp taken at the

time the input data was sampled,
which is in terms of coordinated
system time. This is a 64 bit
quantity in microseconds coordinated
across the rack. This must be
addressed in 32 bit segments as an
array.

If8h0Input.TimeStamp INT DEC This is the timestamp taken at time

the input data was sampled, which is
shown in milliseconds relative solely
to the individual module.

If8h0Input.HartData SINT[40] DEC An array of 40 bytes which contains

HART packet data for the entir more
details.

Accessing TheAccessing The

Accessing The

Accessing TheAccessing The
Module Module

Module

Module Module

TT

T

TT

aa

a

aa

gsgs

gs

gsgs

1.) Select Controller Tags

2.) Right-click to display the

menu

3.) Select Monitor Tags

When you access tags to change configuration or monitor the I/O data
exchange, you have two options.:

•

Monitor tags - option allows you to view tags and change their values.

•

Edit tags - option allows you to add or delete tags, but not to change

their values.

48 ControlLogix™ Analog HART Modules

You can view tags here.

Click on the tag name of the
data structure you want to see

Configuration in formation is
listed for each channel on the
module

ChangingChanging

Changing

ChangingChanging
ConfigurationConfiguration

Configuration

ConfigurationConfiguration
InfInf

oror

mama

Inf

or

InfInf

oror

the the

the

the the

1.) Click on the far left
side of the Value
column an a pulldown
menu appears.

tion ation a

ma

tion a

mama

tion ation a

TT

aa

gsgs

T

a

gs

TT

aa

gsgs

Chapter 5: 1756sc-IF8H Channel Configuration, Data, and Status 49

tt

t

tt

There are two ways to change the configuration:

•

Use a pulldown menu

•

Highlight the value of a particular feature for a particular point and

type a new value

Pulldown menu

2.) Highlight the point that
needs to be changed and type a
valid new value

Highlight value

50 ControlLogix™ Analog HART Modules

1.) Highlight the value of

the feature you want to
change

2.) Type in the valid new

value.

Chapter 6: 1756sc-OF8H Channel Configuration, Data, and Status 51

Configuration, Data,Configuration, Data,

Configuration, Data,

Configuration, Data,Configuration, Data,

Chapter 6

and Staand Sta

and Sta

and Staand Sta
for the 1756sc-OF8Hfor the 1756sc-OF8H

for the 1756sc-OF8H

for the 1756sc-OF8Hfor the 1756sc-OF8H

Read this chapter to:

• Send configuration data to the module

• Configuration tags

• Input tags

• Output tags

• Accessing the module tags

•

Changing configuration information at the tags

This chapter outlines the detailed settings for the 1756sc-OF8H. These
settings determine the modules input types, scan rates, and various
attributes. Detailed descriptions of these settings are available in the Tag
Definition section of this chapter.

tus tus

tus

tus tus

TT

T

TT

aa

a

aa

gsgs

gs

gsgs

SendSend

Send

SendSend
ConfigurationConfiguration

Configuration

ConfigurationConfiguration
Data to theData to the

Data to the

Data to theData to the
ModuleModule

Module

ModuleModule

Note: The following format is used to describe tags

Tag Name Data Type Style Description

After changing the configuration tags in this chapter you must then send
them to the module. To do this you may perform any of these operations:

1. Inhibit then un-inhibit the module via the module properties dialog,
Connection Tab

2. Reset the module via the modules properties dialog. Module Info tab.

3. Reset the module via ladder logic. See the “DoReset” rung in the
sample ladder located in Chapter 8.

4. Perform a “Set Attribute All” or Module Reconfigure message
instruction via ladder logic. Refer to Chapter 8 for information about the
“DoSetAttrAll” command.

Note: If an invalid configuration is sent to the module a connection error
will occur. See chapter 9 for a list of error codes.

52 ControlLogix™ Analog HART Modules

ConfigurationConfiguration

Configuration

ConfigurationConfiguration
TT

aa

gs fgs f

T

a

gs f

TT

aa

gs fgs f

1756sc-OF8H1756sc-OF8H

1756sc-OF8H

1756sc-OF8H1756sc-OF8H

or theor the

or the

or theor the

The following tags allow for custom configuration of the module. These
tags can be found within the controller scope under the tag name
Of8h0Configuration.

Tag Nam e Data Type Style De scription

Of8h0Configuration Of8hConfigurationBlock NA Module configuration
Of8h0Configuration.ConfigRevision SINT DEC Controls multiple owner connections.

Of8h0Configuration.ProgToFaultEn SINT DEC The program to fault enable bit

Of8h0Configuration.Spare INT DEC Unused

Of8h0Configuration.ChXConfigBit s

Of8h0Configuration.ChXConfigBit s.0

Of8h0Configuration.ChXConfigBit s.1

1

X represents the module channel number (0 to 7).

1

1

1

Table 6.1a

0 = Always connect , overwrite w/new
configuration.
1 = Only c onnect if configuration
matches existing configuration.

determines how the outputs should
behave if a communicat ions fault
were to occur while the output
module is in the program mode.
0 = Outputs will remain in their
configured program state despite a
communications fault occurring.
1 = will cause t he outputs to
transition to their programmed fault
state if a communications fault
occurs while in t he program state.

Set to zero

INT BIN This is a s et of individual channel

configuration bits which enable
various functions for the ass ociated
channel.

BOOL DEC Enables ramping of the output value

to a us er defined fault value
(ChXFaultValue)
0 = Feature disabled
1 = During a fault condition the
associated channel will ramp to the
value stored in the ChXFaultValue tag
at a rate defined by the value stored
in the ChXMaxRampRate.

BOOL DEC Enables ramping of the output value

to a user defined idle value
(ChXIdleValue)
0 = Feature disabled
1 = When the PLC is in program
mode the assoc iated channel will
ramp to the value stored in the
ChXIdleValue tag at a rate defined by
the value stored in the
ChXMaxRampRate.

Chapter 6: 1756sc-OF8H Channel Configuration, Data, and Status 53

Table 6.1b

Tag Name Data Type Style Description

1

Of8h0Configuration.ChXConfigBits.2

BOOL DEC Enables ramping of the output value

when the PLC is in RUN mode.
0 = Feature disabled
1 = When the PLC is in RUN mode
the associated channel will ramp to a
new output level at a rate defined by
the value stored in the
ChXMaxRampRat e t ag.

1

Of8h0Configuration.ChXConfigBits.3

BOOL DEC Selects the behavior of the output

channel when transitioning into
Program mode.
0 = Hold last state
1 = go to the value stored in the
ChXIdleValue tag.

1

Of8h0Configuration.ChXConfigBits.4

BOOL DEC Selects the behavior of the output

channel when a communication fault
occurs.
0 = Hold last state
1 = go to the value stored in the
ChXFaultValue tag.

1

Of8h0Configuration.ChXConfigBits.5

BOOL DEC Enables latching for the clamp limit

alarms.
0 = Feature disabled
1 = Clamp limit alarm will remain set
until an unlatch service is explicitly
sent to the channel or alarm.

1

Of8h0Configuration.ChXConfigBits.6

BOOL DEC Enables latching for all four process

alarms: low, low low, high, and high
high.
0 = Alarms unlatched
1 = process alarms will remain set
until an unlatch service is explicitly
sent to the channel or alarm.

1

Of8h0Configuration.ChXConfigBits.7

BOOL DEC Disable alarms

0 = Alarms enabled
1 = Disable all alarms

1

X represents the module channel number (0 to 7).

54 ControlLogix™ Analog HART Modules

Tag Name Data Type Style Description

Of8h0Configuration.ChXConfigBits.8

Of8h0Configuration.ChXConfigBits.9

Of8h0Configuration.ChXConfigBits.10

Of8h0Configuration.ChXConfigBits.11

Of8h0Configuration.ChXConfigBits.12

Of8h0Configuration.ChXConfigBits.13

Of8h0Configuration.ChXConfigBits.14

Of8h0Configuration.ChXConfigBits.15

Of8h0Configuration.ChXOutputRange

Of8h0Configuration.ChXMaxRampRate

Of8h0Configuration.ChXFaultValue

1

X represents the module channel number (0 to 7).

1

Table 6.1c

1

BOOL DEC Hold for initialization

0 = Feature disabled
1 = The channel will hold, or not
change, until initialized with a value
within 0.1% of full scale of its current
value when one of the following
conditions occurs: Module initial
connection (power-up), module
transitions from program mode back
to run mode, module reestablishes
communicati on after a fault.

1

BOOL DEC Enables HART communication for the

channel.
0 = HART disabled
1 = HART Enabled

1

BOOL DEC Unused

Set to zero

1

BOOL DEC Unused

Set to zero

1

BOOL DEC Unused

Set to zero

1

BOOL DEC Unused

Set to zero

1

BOOL DEC Unused

Set to zero

1

BOOL DEC Unused

Set to zero

1

INT DEC Configures the channel’s output

range.
0 = +/-10 VDC
1 = 0 to 20mA
2 = 4 to 20mA

1

FLOAT REAL Configures the maximum rate at

which the output value may change.
Active only if bits 0, 1 or 2 are set in
the ChXConfigBits tag. Entered in
user sc aling units per second.
Defines the value, in engineering
units, t he output should take if a
communications fault occurs when bit
0 is set in the ChXConfigBits tag.

Chapter 6: 1756sc-OF8H Channel Configuration, Data, and Status 55

Table 6.1d

Tag Name Data Type Style Description

Of8h0Configuration.ChXIdleValue

1

FLOAT REAL Defines the value, in engineering

units, the output should take when
the connection transitions to Program
mode. This function is only ac tive
when bit 1 is set in the ChXConfigBits
tag.

Of8h0Configuration.ChXLowSignal

1

FLOAT REAL One of four points used in scaling.

The low signal represents the
minimum output range.

Of8h0Configuration.ChXHighSignal

1

FLOAT REAL One of four points used in scaling.

The high signal represents the
maximum output range.

1

Of8h0Configuration.ChXLowEngineering

FLOAT REAL One of four points used in scaling.

The low engineering represents the
minimum scaled range.

1

Of8h0Configuration.ChXHighEngineering

FLOAT REAL One of four points used in scaling.

The high engineering represents the
maximum scaled range.

Of8h0Configuration.ChXLowClamp

1

FLOAT REAL Defines the minimum analog output

value the channel is allowed to
achieve.

Of8h0Configuration.ChXHighClamp

1

FLOAT REAL Defines the maximum analog output

value the channel is allowed to
achieve.

Of8h0Configuration.ChXCalBias

1

FLOAT REAL A us er configurable offset added

directly to the measured analog value
for the channel.

Of8h0Configuration.ChXSlot0Code

1

SINT DEC HART slot 0 transmitter variable

assignment code. Refer to chapter 7
for more information.

Of8h0Configuration.ChXSlot1Code

1

SINT DEC HART slot 1 transmitter variable

assignment code. Refer to chapter 7
for more information.

Of8h0Configuration.ChXSlot2Code

1

SINT DEC HART slot 2 transmitter variable

assignment code. Refer to chapter 7
for more information.

Of8h0Configuration.ChXSlot3Code

1

SINT DEC HART slot 3 transmitter variable

assignment code. Refer to chapter 7
for more information.

1

X represents the module channel number (0 to 7).

56 ControlLogix™ Analog HART Modules

Table 6.1e

Tag Name Data Type Style Description

Of8h0Configuration.HandleTimeout INT DEC There is a handle timeout associated

with the final reply mess age. After
the module obtaines the requested
information from the HART device, it
will start the HandleTimeout timer
(duration defined by the
HandleTimeout tag). The replay
message will be kept in memory
during the HandleTimeout period.
After the timeout occurs or after the
message is retrieved by the pass­through respons e query command,
the storage buffer will be discarded,
and another pass through message
will be serviced without being
rejected. HandleTimeout is in the

range of 1 to 255 sec onds.
Of8h0Configuration.ModuleConfigBits INT BIN Module function settings
Of8h0Configuration.ModuleConfigBits.0 BOOL DEC Reserved set to zero
Of8h0Configuration.ModuleConfigBits.1 BOOL DEC Reserved set to zero
Of8h0Configuration.ModuleConfigBits.2 BOOL DEC Reserved set to zero
Of8h0Configuration.ModuleConfigBits.3 BOOL DEC Reserved set to zero
Of8h0Configuration.ModuleConfigBits.4 BOOL DEC Reserved set to zero
Of8h0Configuration.ModuleConfigBits.5 BOOL DEC Reserved set to zero
Of8h0Configuration.ModuleConfigBits.6 BOOL DEC Reserved set to zero
Of8h0Configuration.ModuleConfigBits.7 BOOL DEC Reserved set to zero
Of8h0Configuration.ModuleConfigBits.8 BOOL DEC Reserved set to zero
Of8h0Configuration.ModuleConfigBits.9 BOOL DEC Reserved set to zero
Of8h0Configuration.ModuleConfigBits.10 BOOL DEC Reserved set to zero
Of8h0Configuration.ModuleConfigBits.11 BOOL DEC Reserved set to zero
Of8h0Configuration.ModuleConfigBits.12 BOOL DEC Reserved set to zero
Of8h0Configuration.ModuleConfigBits.13 BOOL DEC Reserved set to zero

Chapter 6: 1756sc-OF8H Channel Configuration, Data, and Status 57

Table 6.1f

Tag Name Data Type Style Description

Of8h0Configuration.ModuleConfigBits.14

Of8h0Configuration.ModuleConfigBits.15

2

The configuration of bits 14 and 15 directly effec t the update time of the HART data acquisition for the module, f or

example if bit 15 is set, the HART update time for each channel w ill be doubled.

2

BOOL DEC Bits 14 and 15 determine how often

the pass-through command is
serviced by the module.
15,14 = 00 = pass-through serviced
once per two channels scanned
15,14 = 01 = pass-through serviced
once per module scan
15,14 = 1X = pass-through servic ed

2

BOOL DEC Bits 14 and 15 determine how often

once per channel scan

the pass-through command is
serviced by the module.
15,14 = 00 = pass-through serviced
once per two channels scanned
15,14 = 01 = pass-through serviced
once per module scan
15,14 = 1X = pass-through servic ed
once per channel scan

Input Input

Input

Input Input

TT

T

TT

aa

a

aa

gsgs

gs

gsgs

The following fault and status reporting and module data sections allow
monitoring of faults, status, and input data from the module. These tags
can be found within the Of8h0Input controller tag.

58 ControlLogix™ Analog HART Modules

Tag Name Data Type Style Description

Of8h0Input Of8h0InputBlock NA Module input data

Of8h0Input.ModuleStatus DINT BIN General module status
Of8h0Input.ModuleStatus.0 BOOL DEC Channel 0 general fault status

Of8h0Input.ModuleStatus.1 BOOL DEC Channel 1 general fault status

Of8h0Input.ModuleStatus.2 BOOL DEC Channel 2 general fault status

Of8h0Input.ModuleStatus.3 BOOL DEC Channel 3 general fault status

Of8h0Input.ModuleStatus.4 BOOL DEC Channel 4 general fault status

Of8h0Input.ModuleStatus.5 BOOL DEC Channel 5 general fault status

Of8h0Input.ModuleStatus.6 BOOL DEC Channel 6 general fault status

Of8h0Input.ModuleStatus.7 BOOL DEC Channel 7 general fault status

Of8h0Input.ModuleStatus.8 BOOL DEC Loop output fault

Of8h0Input.ModuleStatus.9 BOOL DEC Unused
Of8h0Input.ModuleStatus.10 BOOL DEC Unused
Of8h0Input.ModuleStatus.11 BOOL DEC Unused
Of8h0Input.ModuleStatus.12 BOOL DEC Unused
Of8h0Input.ModuleStatus.13 BOOL DEC Unused
Of8h0Input.ModuleStatus.14 BOOL DEC Unused
Of8h0Input.ModuleStatus.15 BOOL DEC Unused

Table 6.2a

0 = No fault
1 = Fault

0 = No fault
1 = Fault

0 = No fault
1 = Fault

0 = No fault
1 = Fault

0 = No fault
1 = Fault

0 = No fault
1 = Fault

0 = No fault
1 = Fault

0 = No fault
1 = Fault

0 = No Fault
1 = Fault

Chapter 6: 1756sc-OF8H Channel Configuration, Data, and Status 59

Table 6.2b

Tag Name Data Type Style Description

Of8h0Input.ModuleStatus.16 BOOL DEC Channel 0 HART out-of-service

0 = In service
1 = Out-of-service

Of8h0Input.ModuleStatus.17 BOOL DEC Channel 1 HART out-of-service

0 = In service
1 = Out-of-service

Of8h0Input.ModuleStatus.18 BOOL DEC Channel 2 HART out-of-service

0 = In service
1 = Out-of-service

Of8h0Input.ModuleStatus.19 BOOL DEC Channel 3 HART out-of-service

0 = In service
1 = Out-of-service

Of8h0Input.ModuleStatus.20 BOOL DEC Channel 4 HART out-of-service

0 = In service
1 = Out-of-service

Of8h0Input.ModuleStatus.21 BOOL DEC Channel 5 HART out-of-service

0 = In service
1 = Out-of-service

Of8h0Input.ModuleStatus.22 BOOL DEC Channel 6 HART out-of-service

0 = In service
1 = Out-of-service

Of8h0Input.ModuleStatus.23 BOOL DEC Channel 7 HART out-of-service

0 = In service

1 = Out-of-service
Of8h0Input.ModuleStatus.24 BOOL DEC Unused
Of8h0Input.ModuleStatus.25 BOOL DEC Calibration fault

0 = No fault

1 = Fault
Of8h0Input.ModuleStatus.26 BOOL DEC Calibration in progress

0 = Calibration NOT active

1 = Calibrating
Of8h0Input.ModuleStatus.27 BOOL DEC Unused
Of8h0Input.ModuleStatus.28 BOOL DEC Unused
Of8h0Input.ModuleStatus.29 BOOL DEC Unused
Of8h0Input.ModuleStatus.30 BOOL DEC Unused
Of8h0Input.ModuleStatus.31 BOOL DEC Analog group fault

0 = No fault

1 = Fault

60 ControlLogix™ Analog HART Modules

Tag Name Data Type Style Description

Of8h0Input.ChanStatus SINT[8] BIN An array of 8 SINT which display

1

Of8h0Input.ChanStatus[X]
Of8h0Input.ChanStatus[X].0

Of8h0Input.ChanStatus[X].1

Of8h0Input.ChanStatus[X].2

Of8h0Input.ChanStatus[X].3

Of8h0Input.ChanStatus[X].4

Of8h0Input.ChanStatus[X].5

Of8h0Input.ChanStatus[X].6
Of8h0Input.ChanStatus[X].7

SINT BIN General channel status byte

1

BOOL DEC User value exceeded high clamp

1

BOOL DEC User value exceeded low clamp limit.

1

BOOL DEC Specified ramp rate exceeded.

1

BOOL DEC Channel holding last output value.

1

BOOL DEC Channel calibration fault

1,2

BOOL DEC Invalid or NaN channel value

1

BOOL DEC Unused

1

BOOL DEC Open wire fault (Current Only)

Of8h0Input.ChanData REAL[8] FLOAT An array of 8 floating point registers

Of8h0Input.ChanData[X]

1

X represents the module channel number (0 to 7).

2

An invalid data value is being used f or the associated channel's output tag (i.e. Of8h0.Output.ChXData)

1

REAL FLOAT Channel analog data in engineering

Table 6.2c

general status for each channel.

limit.
0 = No alarm
1 = Alarm

0 = No alarm
1 = Alarm

0 = No alarm
1 = Alarm

0 = Normal
1 = Holding

0 = No fault
1 = Fault

0 = No alarm
1 = Alarm

0 = No fault
1 = Fault

which dis play the analog data for
each channel in engineering units.

units

Chapter 6: 1756sc-OF8H Channel Configuration, Data, and Status 61

Table 6.2d

Tag Name Data Type Style Description

Of8h0Input.CST DINT[2] DEC This is the timestamp taken at the

time the input data was sampled,
which is in terms of coordinated
system time. This is a 64 bit
quantity in microseconds coordinated
across the rack. This must be
addressed in 32 bit segments as an
array.

Of8h0Input.TimeStamp INT DEC This is the times tamp taken at time

the input data was sampled, which is
shown in milliseconds relative solely
to the individual module.

Of8h0Input.HartData SINT[40] DEC An array of 40 bytes which contains

HART packet data for the entir more
details.

Output Output

Output

Output Output

Tag Name Data Type Style Description

Of8h0Output Of8hOutputBlock NA Module output data
Of8h0Output.Ch0Data FLOAT REAL Controls the analog output signal for

Of8h0Output.Ch1Data FLOAT REAL Controls the analog output signal for

Of8h0Output.Ch2Data FLOAT REAL Controls the analog output signal for

Of8h0Output.Ch3Data FLOAT REAL Controls the analog output signal for

Of8h0Output.Ch4Data FLOAT REAL Controls the analog output signal for

Of8h0Output.Ch5Data FLOAT REAL Controls the analog output signal for

Of8h0Output.Ch6Data FLOAT REAL Controls the analog output signal for

Of8h0Output.Ch7Data FLOAT REAL Controls the analog output signal for

TT

T

TT

aa

a

aa

gsgs

gs

gsgs

The output tags are used to control the analog signals for each channel.
See the table below for more details.

Table 6.3

channel 0

channel 1

channel 2

channel 3

channel 4

channel 5

channel 6

channel 7

62 ControlLogix™ Analog HART Modules

Accessing TheAccessing The

Accessing The

Accessing TheAccessing The
Module Module

Module

Module Module

TT

T

TT

aa

a

aa

gsgs

gs

gsgs

When you access tags to change configuration or monitor the I/O data
exchange, you have two options.:

•

Monitor tags - option allows you to view tags and change their values.

•

Edit tags - option allows you to add or delete tags, but not to change

their values.

1.) Select Controller Tags

2.) Right-click to display the

menu

3.) Select Monitor Tags

Click on the tag name of the
data structure you want to see

Chapter 6: 1756sc-OF8H Channel Configuration, Data, and Status 63

You can view tags here.

Configuration information is
listed for each chann el on the
module

64 ControlLogix™ Analog HART Modules

ChangingChanging

Changing

ChangingChanging
ConfigurationConfiguration

Configuration

ConfigurationConfiguration
InfInf

oror

mama

Inf

or

InfInf

oror

the the

the

the the

tion ation a

ma

tion a

mama

tion ation a

TT

aa

gsgs

T

a

gs

TT

aa

gsgs

tt

t

tt

There are two ways to change the configuration:

•

Use a pulldown menu

•

Highlight the value of a particular feature for a particular point and

type a new value

Pulldown menu

1.) Click on the far left
side of the Value
column and a pulldown
menu appears.

2.) Highlight the point that
needs to be changed and type a
valid new value

1.) Highlight the value of

the feature you want to
change

2.) Type in the valid new

value.

Chapter 6: 1756sc-OF8H Channel Configuration, Data, and Status 65

Highlight value

66 ControlLogix™ Analog HART Modules

Configuring theConfiguring the

Configuring the

Configuring theConfiguring the
Modules forModules for

Modules for

Modules forModules for
HARTHART

HART

HARTHART

Chapter 7: HART Channel Configuration, Data, and Status 67

Enabling and Using HART on theEnabling and Using HART on the

Enabling and Using HART on the

Enabling and Using HART on theEnabling and Using HART on the
1756sc-IF8H and OF8H1756sc-IF8H and OF8H

1756sc-IF8H and OF8H

1756sc-IF8H and OF8H1756sc-IF8H and OF8H

This chapter outlines the detailed settings and configuration related to
HART communication for the 1756sc-IF8H and 1756sc-OF8H modules.
These settings determine how the modules acquire HART data.

The chapter is broken down into the following sections:

• Configuring the modules for HART

• How the modules send and receive HART data

• HART protocol overview

ConfConf

Conf

ConfConf
Acquisition/Communication)Acquisition/Communication)

Acquisition/Communication)

Acquisition/Communication)Acquisition/Communication)

iguring the IF8H Module figuring the IF8H Module f

iguring the IF8H Module f

iguring the IF8H Module figuring the IF8H Module f

Chapter 7

or (Haror (Har

or (Har

or (Haror (Har

tt

t

tt

•

In order for HART to be active on any given channel, the channel

configuration must contain the following basic settings:

•

Bit 7 (Enable HART), in the If8h0Configuration.ChXConfigBits tag,

needs to be set. See chapter 5 for more details.

•

An appropriate ADC filter range must be selected.

Attention: The 1000Hz ADC filter setting is notAttention: The 1000Hz ADC filter setting is not

Attention: The 1000Hz ADC filter setting is not

Attention: The 1000Hz ADC filter setting is notAttention: The 1000Hz ADC filter setting is not

!

allowed when HART is enabled.allowed when HART is enabled.

allowed when HART is enabled.

allowed when HART is enabled.allowed when HART is enabled.

•

The If8h0Configuration.ChXInputRange tag must be set to 4 for a 4 to

mA current range.

Attention: Attention:

Attention:

Attention: Attention:

!

improved by disabling HART communication on improved by disabling HART communication on

improved by disabling HART communication on

improved by disabling HART communication on improved by disabling HART communication on

channels or channels that include non-HART devices.channels or channels that include non-HART devices.

channels or channels that include non-HART devices.

channels or channels that include non-HART devices.channels or channels that include non-HART devices.

HART throughput time can beHART throughput time can be

HART throughput time can be

HART throughput time can beHART throughput time can be

unusedunused

unused

unusedunused

68 ControlLogix™ Analog HART Modules

Figure 7.1 (Channel 0 Configuration Example)

ConfConf

Conf

ConfConf
Acquisition/Communication)Acquisition/Communication)

Acquisition/Communication)

Acquisition/Communication)Acquisition/Communication)

iguring the OF8H Module figuring the OF8H Module f

iguring the OF8H Module f

iguring the OF8H Module figuring the OF8H Module f

or (Haror (Har

or (Har

or (Haror (Har

tt

t

tt

In order for HART to be active on any given channel, the channel
configuration must contain the following basic settings:

•

Bit 9 (Enable HART), in the Of8h0Configuration.ChXConfigBits tag,

needs to be set. See chapter 6 for more details.

•

The Of8h0Configuration.ChXOutputRange tag must be set to 2 for a 4

to 20 mA current range.

Attention: Attention:

Attention:

Attention: Attention:

!

improved by disabling HART communication on improved by disabling HART communication on

improved by disabling HART communication on

improved by disabling HART communication on improved by disabling HART communication on

channels or channels that include non-HART devices.channels or channels that include non-HART devices.

channels or channels that include non-HART devices.

channels or channels that include non-HART devices.channels or channels that include non-HART devices.

HART throughput time can beHART throughput time can be

HART throughput time can be

HART throughput time can beHART throughput time can be

unusedunused

unused

unusedunused

Chapter 7: HART Channel Configuration, Data, and Status 69

Figure 7.2 (Channel 0 Configuration Example)

How theHow the

How the

How theHow the
Modules SendModules Send

Modules Send

Modules SendModules Send
and Receiveand Receive

and Receive

and Receiveand Receive
HART DataHART Data

HART Data

HART DataHART Data

How the Module Connects to a Field DeviceHow the Module Connects to a Field Device

How the Module Connects to a Field Device

How the Module Connects to a Field DeviceHow the Module Connects to a Field Device

Both the HART input and Output module behave as a HART master in
which case the field device is considered the slave. In other words, the
master must initiate the communication with the field device and the
device simply replies with an appropriate response. Any given channel
may have a master, a secondary master (hand held configuration tool), and
a slave connected simultaneously. Please see Figure 3.

70 ControlLogix™ Analog HART Modules

Figure 7.3 (Primary, Secondary and Slave connection)

Attention:Attention:

Attention:

Attention:Attention:

!

the IF8H or the OF8H.the IF8H or the OF8H.

the IF8H or the OF8H.

the IF8H or the OF8H.the IF8H or the OF8H.

Har Har

Har

Har Har

t mt m

t m

t mt m

ulti-drulti-dr

ulti-dr

ulti-drulti-dr

op is not supporop is not suppor

op is not suppor

op is not supporop is not suppor

ted bted b

ted b

ted bted b

yy

y

yy

HART modules communicate using two different messaging schemes
connected and unconnected. Connected messages are messages that are
periodically updated and maintained by the ControlLogix processor. The
frequencies of the updates are adjustable and are defined by the user.
Connected messages include data contained in the module’s input image,
and in the case of the OF8H module, the output image. Unconnected
messages are messages that are transmitted over the control network and
are performed asynchronously from the normal processor scan.
Unconnected messages include data contained in the module’s
configuration image (i.e. Local:e:C), and CIP messages such as the
module specific commands. Module specific commands include the
HART pass-through commands, HART suspension and resume, and the
get HART device information command.

Chapter 7: HART Channel Configuration, Data, and Status 71

Figure 7.4 (Connected and Unconnected messaging)

• Analog data

Connected

Unconnected

• Module status

• HART Dynamic

Variables

• HART device codes

• Module Configuration

• Any CIP message

• HART Pass-Through

The module uses the two communication schemes to gather HART data.
Gathering HART data is accomplished using two processes auto
acquisition, and or using the module specific commands.

Auto AcquisitionAuto Acquisition

Auto Acquisition

Auto AcquisitionAuto Acquisition

When a channel is configured for HART, the module will automatically
search and establish a connection to any HART field device wired to the
channel. Once the module establishes a connection it will begin to acquire
HART data, including device specific codes (i.e. Manufacturer ID, serial
number, etc.), the four dynamic variables, extended device status, slot
variables (OF8H only), and any stored ASCII message descriptor that
may be present. The HART data retrieved automatically by the module is
then displayed in the input image and is accessible by ladder logic. The
HART data will update, on average, every 6.5 seconds if all eight channels
are enabled for HART. The module initiates the connection by sending a
string of HART commands to the field device. Please see figure below.

72 ControlLogix™ Analog HART Modules

Figure 7.5 (Auto Acquisition Flow)

Start

Initialized

for

HART?

YES

Channel

Switch

Connect to field

device

Read device

codes

NO

Read ASCII

messages

Read PVU and

PVL

Read 4 dynamic

variables

Read extended

status

Read slot variables

(OF8H Only)

The data that is collected from the process described in figure 7.5 is
buffered to the modules RAM memory. Since the amount of data
returned from the auto-acquisition process is extensive, utilizing the module
input tags efficiently would not be practical unless the data is multiplexed.
Therefore, the data is multiplexed into five separate packets and for each
individual channel. The packets are defined in tables 7.1 to 7.5.

Chapter 7: HART Channel Configuration, Data, and Status 73

Table 7.1(Packet 0)

Tag Name Data Type

(If8h0 or Of8h0)Packet0

1

Packet0[8,1] NA Two dimmensional array containing

Style

Description

packet 0 data for all 8 channels.

(If8h0 or Of8h0)Packet0[X,0]

1,2

(If8h0 or Of8h0)Packet0[X,0].HartChannelID INT BIN

Packet0 NA Packet 0 data for channel X

Bits 0 to 3: Channel number (0 – 7).
Bit 4: Searching/Initializing HART device
Bit 5: HART communication failure or
device not found
Bit 6: Pass-through message pending
(ready)
Bit 7: Unu s ed (0)
Bits 8 to 10: Packet ID
Bit 11 through 15: Unused

(If8h0 or Of8h0)Packet0[X,0].ManufacturerID SINT DEC
(If8h0 or Of8h0)Packet0[X,0].DeviceType SINT DEC
(If8h0 or Of8h0)Packet0[X,0].NumPreambles SINT DEC

HART device Manufacturer ID
HART device type code
Minimum number of preambles the device
req uires.

(If8h0 or Of8h0)Packet0[X,0].UniversalCmdCode SINT DEC
(If8h0 or Of8h0)Packet0[X,0].XmitterRev SINT DEC
(If8h0 or Of8h0)Packet0[X,0].SwRev SINT DEC
(If8h0 or Of8h0)Packet0[X,0].HwRev SINT DEC
(If8h0 or Of8h0)Packet0[X,0].HartFlags SINT BIN
(If8h0 or Of8h0)Packet0[X,0].RangeUnits SINT DEC
(If8h0 or Of8h0)Packet0[X,0].DeviceSerialNumber SINT[3] HEX
(If8h0 or Of8h0)Packet0[X,0].DeviceTag SINT[8] ASCII

HART Univ ersal command code
HART Transmitter specific revision
HART device software revision number
HART device hardware revision number
HART flags
Units code for range parameter
HART device ID number
8 character device tag

(If8h0 or Of8h0)Packet0[X,0].DeviceDescriptor SINT[16] ASCII

1

The name in parentheses repres ents the module tag name (i.e. If 8h0 or Of8h0) depending on w hich module is being used.

2

X represents the module channel number (0 to 7)

74 ControlLogix™ Analog HART Modules

Table 7.2(Packet 1)

Tag Name Data Type

(If8h0 or Of8h0)Packet1

1

Packet1[8,1] NA Two dimensional array containing

Style

Des cri ption

packet 1 data for all 8 channels.

(If8h0 or Of8h0)Packet1[X,0]

1,2

(If8h0 or Of8h0)Packet1[X,0].HartChannelID INT BIN

Packet1 NA Pac ket 1 data for channel X

Bits 0 to 3: Chann el number (0 – 7).
Bit 4: Searching/Initializing HART device
Bit 5: HART communication failure or
device not found
Bit 6: Pass-through message pending
(ready)
Bit 7: Unused (0)
Bits 8 to 10: Packet ID
Bit 11 through 15: Unused

(If8h0 or Of8h0)Packet1[X,0].HartCommStatus SINT BIN

(If8h0 or Of8h0)Packet1[X,0].HartDevStatus SINT BIN

(If8h0 or Of8h0)Packet1[X,0].HartPV REAL FLOAT
(If8h0 or Of8h0)Packet1[X,0].HartSV REAL FLOAT
(If8h0 or Of8h0)Packet1[X,0].HartTV REAL FLOAT
(If8h0 or Of8h0)Packet1[X,0].HartFV REAL FLOAT
(If8h0 or Of8h0)Packet1[X,0].HartPVUnits SINT DEC
(If8h0 or Of8h0)Packet1[X,0].HartSVUnits SINT DEC
(If8h0 or Of8h0)Packet1[X,0].HartTVUnits SINT DEC
(If8h0 or Of8h0)Packet1[X,0].HartFVUnits SINT DEC
(If8h0 or Of8h0)Packet1[X,0].PV_Assignment SINT DEC
(If8h0 or Of8h0)Packet1[X,0].SV_Assignment SINT DEC
(If8h0 or Of8h0)Packet1[X,0].TV_Assignment SINT DEC
(If8h0 or Of8h0)Packet1[X,0].FV_As signment SINT DEC
(If8h0 or Of8h0)Packet1[X,0].RangeLow REAL FLOAT

HART communication status byt e. Refer to
appendix D for more details.

HART device status byt e. Refer to appendix D
for more details.

HART P rimary Variable

HART Secondary Variable

HART Tertiary Variable

HART Fo urth Variable

HART P rimary Variable unit s code

HART Secondary Variable units code

HART T ertiary Variable unit s code

HART Fo urt h Variable units co de

HART P rimary Variable co de

HART Secondary Variable code

HART Tertiary Variable code

HART Fo urth Variable code

Low transmitter range for analog signal in
engineering units

(If8h0 or Of8h0)Packet1[X,0].RangeHi REAL FLOAT

High transmitter range for analog signal in
engineering units

(If8h0 or Of8h0)Packet1[X,0].Pad SINT[4] DEC

1

The name in parentheses represents the module tag name (i.e. If8h0 or Of8h0) depending on w hich module is being used.

2

X represents the module channel number (0 to 7)

Packet pad (32 bit alignment)

Chapter 7: HART Channel Configuration, Data, and Status 75

Table 7.3 (Packet 2)

Tag Name Data Type

(If8h0 or Of8h0)Packet2

1

Packet2[8,1] NA Two dimensional array containing

Style

Description

packet 2 data for all 8 channels.

(If8h0 or Of8h0)Packet2[X,0]

1,2

(If8h0 or Of8h0)Packet2[X,0].HartChannelID INT BIN

Packet2 NA Packet 2 data for channel X

Bits 0 to 3: Chann el number (0 – 7).
Bit 4: Searching/Initializing HART device
Bit 5: HART communication failure or
device not found
Bit 6: Pass-through message pending
(ready)
Bit 7: Unu s ed (0)
Bits 8 to 10: Packet ID
Bit 11 through 15: Unused

(If8h0 or Of8h0)Packet2[X,0].Slot0Data REAL Float
(If8h0 or Of8h0)Packet2[X,0].Slot1Data REAL Float
(If8h0 or Of8h0)Packet2[X,0].Slot2Data REAL Float
(If8h0 or Of8h0)Packet2[X,0].Slot3Data REAL Float
(If8h0 or Of8h0)Packet2[X,0].Slot0Units SINT DEC
(If8h0 or Of8h0)Packet2[X,0].Slot1Units SINT DEC
(If8h0 or Of8h0)Packet2[X,0].Slot2Units SINT DEC
(If8h0 or Of8h0)Packet2[X,0].Slot3Units SINT DEC
(If8h0 or Of8h0)Packet2[X,0].Slot0Assignment SINT DEC
(If8h0 or Of8h0)Packet2[X,0].Slot1Assignment SINT DEC
(If8h0 or Of8h0)Packet2[X,0].Slot2Assignment SINT DEC
(If8h0 or Of8h0)Packet2[X,0].Slot3Assignment SINT DEC
(If8h0 or Of8h0)Packet2[X,0].Pad SINT[12] DEC

1

The name in parentheses represents the module tag name (i.e. If8h0 or Of8h0) depending on w hich module is being used.

2

X represents the module channel number (0 to 7)

Variable for s lot 0
Variable for s lot 1
Variable for s lot 2
Variable for s lot 3
Slot 0 units code
Slot 1 units code
Slot 2 units code
Slot 3 units code
Slot 0 variable code
Slot 1 variable code
Slot 2 variable code
Slot 3 variable code
Packet pad

Attention: Slot variables are not acquiredAttention: Slot variables are not acquired

Attention: Slot variables are not acquired

Attention: Slot variables are not acquiredAttention: Slot variables are not acquired

!

automatically by the input module. Therefore, packet 2automatically by the input module. Therefore, packet 2

automatically by the input module. Therefore, packet 2

automatically by the input module. Therefore, packet 2automatically by the input module. Therefore, packet 2

is skipped by the auto-acquisition process.is skipped by the auto-acquisition process.

is skipped by the auto-acquisition process.

is skipped by the auto-acquisition process.is skipped by the auto-acquisition process.

76 ControlLogix™ Analog HART Modules

Table 7.4 (Packet 3)

Tag Name Data Type

(If8h0 or Of8h0)Packet3

1

Packet3[8,1] NA Two dimensional array containing

Style

Des cription

packet 3 data for all 8 channels.

(If8h0 or Of8h0)Packet3[X,0]

1,2

(If8h0 or Of8h0)Packet3[X,0].HartChannelID INT BIN

Packet3 NA Packet 3 data for channel X

Bits 0 to 3: Channel number (0 – 7).
Bit 4: Searching/Initializing HART device
Bit 5: HART communication failure or
device not found
Bit 6: Pass-through message pending
(ready)
Bit 7: Unu s ed (0)
Bits 8 to 10: Packet ID
Bit 11 through 15: Unused

Message SINT[32] ASCII
Pad SINT[4] DEC

1

The name in parentheses repres ents the module tag name (i.e. If8h0 or Of8h0) depending on w hich module is being used.

2

X represents the module channel number (0 to 7)

32 character message
Pad 32 bit alignment.

Table 7.5 (Packet 4)

Tag Name Data Type

(If8h0 or Of8h0)Packet4

1

Packet4[8,1] NA Two dimensional array containing

Style

Description

packet 4 data for all 8 channels.

(If8h0 or Of8h0)Packet4[X,0]

1,2

(If8h0 or Of8h0)Packet4[X,0].HartChannelID INT BIN

Packet4[8,1] NA Packet 4 data for channel X

Bits 0 to 3: Chann el number (0 – 7).
Bit 4: Searching/Initializing HART device
Bit 5: HART communication failure or
device not found
Bit 6: Pass-through message pending
(ready)
Bit 7: Unu s ed (0)
Bits 8 to 10: Packet ID
Bit 11 through 15: Unused

Date SINT[3] DEC
FinalAss emblyNumber SINT[3] DEC

Stored date in the field device
The final assembly number is used for
identifying the materials and electronics
that comprise the field device.

ExtendedSt atus SINT[24] DEC

The extended status returned by HART
co mma nd 48

Pad SINT[3] DEC

1

The name in parentheses repres ents the module tag name (i.e. If8h0 or Of8h0) depending on w hich module is being used.

2

X represents the module channel number (0 to 7)

Pad 32 bit alignment

Note: Not all of the data that is returned by the process outlined in figure

7.5 gets passed to the packets. In order to access the data that is not
passed to the packets, you must execute the appropriate HART message
using the pass-through command, which will be discussed later in this
chapter.

Chapter 7: HART Channel Configuration, Data, and Status 77

The HART data acquired by the auto acquisition process is copied to the
packet tags by using ladder. The ladder simply copies the data stored in
the (If8h0 or Of8h0)Input.HartDatainput tag., which is multiplexed for the
appropriate packet depending on the state of bits 0, 1, 2 and 8, 9, 10, found
in the first two bytes of the tag. Bits 0, 1, 2 determine the current channel
that is being scanned and bits 8, 9, and 10 determine the appropriate
packet. The ladder example, shown in figure 7.6, buffers the data from
the HartDataInput tag to the correct packets for the IF8H module.

Figure 7.6 (Demultiplexing Ladder)

78 ControlLogix™ Analog HART Modules

Note: The ladder in figure 7.6 can be found in the project sample file
located on our website at (www.spectrumcontrols.com)

Module Specific CommandsModule Specific Commands

Module Specific Commands

Module Specific CommandsModule Specific Commands

Both the HART input and output modules provide module specific
commands. The commands are passed to the module using unconnected
messaging. Unconnected messaging simply refers to the ability to
communicate to the module, over a control network (i.e. CNET, Ethernet,
Etc.), without the need of the owner PLC. However, an unconnected
message can be sent from a PLC to the HART module using the MSG
ladder instruction. See figure below.

Figure 7.7 (Message Instruction)

The MSG instruction must be configured correctly to establish
communication to the HART module. Each module specific command
uses the same generic CIP message configuration. The generic CIP
message configuration used by the HART input and output module is
shown in the table below.

Chapter 7: HART Channel Configuration, Data, and Status 79

Table 7.6 (Generic CIP Configuration)

Field Value Definition
Message Type “CIP Generic” Control and Information Protocol (CIP) A native communications protocol used

Service Code 0x32
Class Name 0xB0
Instance Name 0x01
Object Attribute Leave blank
Source ? The tag defining the data sent to the HART module
Number of elements ? The number of elements defined by the command that is used
Destination ? The tag where the reply data will be written

Unconnected Message Header

on Allen-Bradley’s ControlNet communication network.

The MSG configuration screen is then loaded with the data from table 7.6.
See figure below.

Figure 7.8 (Message Configuration Dialog)

After the configuration screen is loaded with the data, the actual module
specific commands are loaded into the MSG source tag. When the MSG
instruction executes, the module specific command is passed to the module
via the MSG "source" tag and the reply data is passed to the MSG
"destination" tag. The module specific commands include, HART

suspension, HART resume, get device information, and the HART pass­through commands. The tables on the following pages show the format

for each module specific command.

Note: The source length should be large enough to accommodate the
HART message string.

80 ControlLogix™ Analog HART Modules

Get HART Device Information

The Get HART Device Information command is used to gather the device
specific information for the connected HART device. The data that is
retrieved can be seen in table 7.7. The information that is gathered by this
command is similar to the information gathered from the auto-acquisition
process. The key difference is that the Get HART Device Information
command pulls the data that has been stored in the module RAM and not
directly from the field device.

Table 7.7 (Get HART Device Information Command)

HART Get Device Information – command message packet structure

Get currently cached Device Information for a given channel.

Field Value Definition

Unconnected Message Header

HART Channel
Number
Command Number 0x03 (1 byte) The command number to obtain

0x00 – 0x07 (1 byte) Module input channel number for

Table 7.8 (Response If Device Information Is Not Available)

HART Get Device Information - reply packet structure

Field Value Definition

Unconnected Message Header

HART Channel
Number

Status (1 byte)

Count (1 byte) Set to 1
Handle 0 Fill byte of zero to

0x00 – 0x07 (1 byte) Module input

34 = RUNNING
35 = DEAD (bad request)

HART command

HART device information

channel number
for HART
command
Command status

keep command
response common
among all replies.

Chapter 7: HART Channel Configuration, Data, and Status 81

Table 7.9 (Response When Device Information Is Available)

HART Get Device Information - reply packet structure

Field Value Definition

Unconnected Message Header

HART Channel Number 0x00 – 0x07 (1 byte) Module input channel number for

Status 00 = SUCCESS Command status

Count (1 byte) Number of data bytes to following.

HARTManufacturerIDCode (1 byte) CMD#0, Byte 1

HARTDeviceTypeCode (1 byte) CMD#0, Byte 2

HARTPreambles (1 byte) CMD#0, Byte 3

HARTUnivCmdCode (1 byte) CMD#0, Byte 4

HARTTransSpecRev (1 byte) CMD#0, Byte 5

HARTSoftwareRevision (1 byte) CMD#0, Byte 6

HARTHardwareRevision (1 byte) CMD#0, Byte 7

HARTFlags (1 byte) CMD#0, Byte 8

HARTDeviceID (3 bytes) Device serial number CMD#0, Bytes 9-11

HARTTag (8 bytes unpacked ASCII) CMD#13, Bytes 0-5

HARTDescriptor (16 bytes unpacked ASCII) CMD#13, Bytes 6-17

HARTDate (3 bytes) CMD#13, Bytes 18-20

HARTFinalAssemblyNumber (3 bytes) CMD#16, Bytes 0-2

HARTMessage (32 bytes unpacked ASCII) CMD#12, Bytes 0-23

HARTPVCode (1 byte) CMD#50, Bytes 0

HARTSVCode (1 byte) CMD#50, Bytes 1

HARTTVCode (1 byte) CMD#50, Bytes 2

HARTFVCode (1 byte) CMD#50, Bytes 3

HARTPVUnits (1 byte) CMD#3, Byte 4

HARTSVUnits (1 byte) CMD#3, Byte 9

HARTTVUnits (1 byte) CMD#3, Byte 14

HARTFVUnits (1 byte) CMD#3, Byte 19

HARTPVLowerRange (4 bytes – Floating Point Value) CMD#15, Bytes 3-6

HARTPVUpperRange (4 bytes – Floating Point Value) CMD#15, Bytes 7-10

HART command

0 if not present

0 if not present

0 if not present

The command status, the second byte in the reply packet for the module
specific command, can return three different responses, SUCCESS,
RUNNING and DEAD. These responses echo the state of the module at
the time the command is sent. The conditions for each response are as
follows:

SUCCESS will be sent back when all of the following conditions are
met:

• Command and HART Channel number are both valid.

• HART channel device information is available.

RUNNING will be sent back when all of the following conditions
are met:

82 ControlLogix™ Analog HART Modules

• Command and HART Channel number are both valid.

• HART channel is enabled and communication has been established,
meaning at least the device addressing information is available.

• HART channel is already in the state of gathering device information.
Reply will be sent back without additional events triggered.

DEAD will be sent back if any of the following conditions is true:

• Command or HART Channel number is invalid

• HART channel is not enabled

• HART communication has not been established, meaning that the 5­byte unique address has not been determined yet.

• All other conditioned not generating RUNNING or SUCCESS.

The following figure demonstrates how a module specific command can
be sent to the module using ladder logic.

Figure 7.9 (Sending a Module Specific Command Using Ladder)

HART Channel Suspension and Resume

Sometimes referred to as "Out of Service" and "In Service" respectively,
these commands can be utilized to suspend or resume operation of an
enabled HART channel. When a HART Suspend Channel command is
sent, the HART module will keep the current HART configuration
information and stop all communication processes on the selected channel.
However, there will be overriding conditions such as configuration change
affecting the overall module operation, which will cause the HART
function to reset based on the new configuration. Normal HART
operation will resume if the HART Resume command is sent to the
module during a HART Suspension.

Chapter 7: HART Channel Configuration, Data, and Status 83

Note: If the resume command is received, without previously receiving a
suspension command, it will be ignored.

Note: The selected channel will resume normal HART operations three
minutes after the Suspension command has been received by the module.
Pass-through for that channel resets the timer to 3 minutes.

Table 7.10 (HART Suspend and Resume Command)

HART Channel Suspend/Resume command request – command message packet structure

Field Value Definition

Unconnected Message Header

HART Channel Number 0x00 – 0x07 (1 byte) Enabled HART channel

Command Number (1 byte)

0x05: Suspend
0x06: Resume

number
The command number to
suspend or resume

Table 7.11 (HART Suspend and Resume Reply Packet)

HART Channel Suspend/Resume command request – reply packet structure

Field Value Definition

Unconnected Message Header

HART Channel Number 0x00 – 0x07 (1 byte) Echo of the HART channel

Status (1 byte)

Count (1 byte) Set to 1

Handle 0 Fill byte of zero to keep

number received

Command status
00 = SUCCESS
35 = DEAD

command response common

among all replies.

The command status, the second byte in the reply packet for the module
specific command, can return two different responses, SUCCESS, and
DEAD. These responses echo the state of the module at the time the
command is sent. The conditions for each response are as follows:

SUCCESS will be sent back under the following conditions:

• Command and HART Channel number are both valid.

• HART channel number is an enabled channel

• The identified HART channel finished all of the start-up connection
process.

• The I/O module will not be checking for matching set of suspend/
resume commands. This means, if already suspended, and receives
another suspend, SUCCESS will be returned still. Similarly if the
system is operating as normal, and receives a resume command, it will

84 ControlLogix™ Analog HART Modules

ignore the command and continue operation. This state of operation
will not be maintained after power-up or when configuration changes.

DEAD will be sent back if any of the following conditions is true:

• Command and HART Channel number are both valid.

• HART channel is not enabled

• HART communication has not been established, meaning that the 5­byte unique address has not been determined yet, or the module is still
obtaining device information.

• All other conditioned not generating SUCCESS.

HART Pass-Through Command

The HART Pass-Through Command can be used to send any HART
command including, universal, common practice or device specific, directly
to a field device. The module in this case could be considered a HART
bridge. There can be two (2) instances of a HART pass-through message
being serviced, meaning the pass-through message queue is 2 deep. The
HART pass-through response will be queued the moment the command is
received, if the queue spaces are not already in use, and be dispatched
after at least a full scan is done. In another word, after servicing a pass­through, the HART module will make sure all enabled HART channels
have updated variable values before another pass-through is placed into
service.

All HART pass-through commands require a series of messages to be
exchanged. First, a pass-through command request must be sent to the
HART module to initiate the pass-through command. The HART module
will respond to the command request with a command request reply that
includes a handle that can be used to obtain the pass-through message
response. Once the handle is received, the user may issue a Get
Command Query to obtain the status of the pass-through command and
the pass-through command response data, if it is available.

There is a handle timeout associated with the final reply message. After
the HART module obtains the requested information from the HART
device, it will start the HandleTimeout (as defined in the Configuration
Tag) timer. The reply message will be kept persistent during the
HandleTimeout period. When the timeout occurs the reply message will
be discarded, and another pass through message will be serviced without
being rejected. The user defined Handle-Timeout is in the range of 1 to
255 seconds.

Chapter 7: HART Channel Configuration, Data, and Status 85

Attention: If the HART message being sent orAttention: If the HART message being sent or

Attention: If the HART message being sent or

Attention: If the HART message being sent orAttention: If the HART message being sent or

!

received using the pass-through command containsreceived using the pass-through command contains

received using the pass-through command contains

received using the pass-through command containsreceived using the pass-through command contains

floating point values, the order of the bytes must befloating point values, the order of the bytes must be

floating point values, the order of the bytes must be

floating point values, the order of the bytes must befloating point values, the order of the bytes must be

reversed.reversed.

reversed.

reversed.reversed.

Depending on the HART command, the data contained within the HART
message may include floating point numbers or double integers. If a
floating point or double integer is contained within the HART message, the
user must be aware that the order of the bytes that make up the float or
double will need to be reversed. The reason for this is related to how the
bytes are stored in the Controllogix processor. The Controllogix processor
stores the bytes in memory in a format referred to as "big-endian". Big­endian is an order in which the "big end" (most significant value in the
sequence) is stored first (at the lowest storage address). However,
HART devices transmit the byte data in the reverse order or as you may
have guessed "little-endian" Refer to chapter 8 for a ladder sample
demonstrating the process of swapping the order of the bytes.

Table 7.12 (HART Pass-Through Command Request)

HART pass through command request – command message packet structure

Field Value Definition

Unconnected Message Header

HART Channel Number 0x00 – 0x07 (1 byte) Module input channel

Command Number 0x01 (1 byte) The command number

HART Command N bytes

N = Length of message – 2

Contents are as follows:

Start or Delimiter (1 byte): 0x82
Long form Address (5 bytes)
Command number (1 byte)
Request Data Count (1 byte)
Data (“Request Data Count” bytes)
Checksum (XOR of all bytes from delimiter on.
Delimiter is included )

number for HART
command

to issue a HART pass­through command.
The actual HART
command PDU

86 ControlLogix™ Analog HART Modules

Table 7.13 (HART Pass-Through Command Request Reply)

HART pass through command request – reply packet structure

Field Value Definition

Unconnected Message Header

HART Channel Number 0x00 – 0x07 (1 byte) Module input channel

Status (1 byte)

Count (1 byte) Set to 1

Handle (1 byte)

33 = INITIATE
35 = DEAD (bad request)

0 (bad when status is DEAD)
1-255 (good)

The command status, the second byte in the reply packet for this module
specific command, can return two different responses, INITIATE, and
DEAD. These responses echo the state of the module at the time the
command is sent. The conditions for each response are as follows:

INITIATE will be sent back under the following conditions:

number for HART
command
Command status

The handle for
command complete
query

• Command and HART Channel number are both valid.

• HART channel is enabled and communication has been established,
meaning at least the device addressing information is available.

• Handle is available, meaning no pending handle is still active.

• HART channel is doing regular data sampling only. No pending device
information gathering is active.

• No pending pass-through handle is active, meaning handle timeout has
not occurred yet.

• Device address and delimiter are valid.

• Received CIP word count is large enough for the entire command
packet.

DEAD will be sent back if any of the following conditions are true:

• Command or HART Channel number is invalid

• HART channel is not enabled

• HART communication has not been established, meaning that the 5­byte unique address has not been determined yet.

• The channel is currently updating device information. Theoretically,
pass-through command can be safely accepted after successfully