FLEX I/O Isolated Input/Output HART Analog Modules User Manual
Important User Information
Read this document and the documents listed in the additional resources section about installation, configuration, and
operation of this equipment before you install, configure, operate, or maintain this product. Users are required to familiarize
themselves with installation and wiring instructions in addition to requirements of all applicable codes, laws, and standards.
Activities including installation, adjustments, putting into service, use, assembly, disassembly, and maintenance are required to
be carried out by suitably trained personnel in accordance with applicable code of practice.
If this equipment is used in a manner not specified by the manufacturer, the protection provided by the equipment may be
impaired.
In no event will Rockwell Automation, Inc. be responsible or liable for indirect or consequential damages resulting from the use
or application of this equipment.
The examples and diagrams in this manual are included solely for illustrative purposes. Because of the many variables and
requirements associated with any particular installation, Rockwell Automation, Inc. cannot assume responsibility or liability for
actual use based on the examples and diagrams.
No patent liability is assumed by Rockwell Automation, Inc. with respect to use of information, circuits, equipment, or software
described in this manual.
Reproduction of the contents of this manual, in whole or in part, without written permission of Rockwell Automation, Inc., is
prohibited.
Throughout this manual, when necessary, we use notes to make you aware of safety considerations.
WARNING: Identifies information about practices or circumstances that can cause an explosion in a hazardous environment, which may
lead to personal injury or death, property damage, or economic loss.
ATTENTION: Identifies information about practices or circumstances that can lead to personal injury or death, property damage, or
economic loss. Attentions help you identify a hazard, avoid a hazard, and recognize the consequence.
IMPORTANT
Identifies information that is critical for successful application and understanding of the product.
Labels may also be on or inside the equipment to provide specific precautions.
SHOCK HAZARD: Labels may be on or inside the equipment, for example, a drive or motor, to alert people that dangerous voltage may
be present.
BURN HAZARD: Labels may be on or inside the equipment, for example, a drive or motor, to alert people that surfaces may reach
dangerous temperatures.
ARC FLASH HAZARD: Labels may be on or inside the equipment, for example, a motor control center, to alert people to potential Arc
Flash. Arc Flash will cause severe injury or death. Wear proper Personal Protective Equipment (PPE). Follow ALL Regulatory requirements
for safe work practices and for Personal Protective Equipment (PPE).
2Rockwell Automation Publication 1794-UM065D-EN-P - April 2020
Preface
Why Read This Manual
Who Should Use This
Manual
About the Vocabulary
This manual shows you how to use your FLEX™ I/O analog modules with the
ControlNet® products and ControlNet network, and Ethernet products and
EtherNet/IP™ network. The manual helps you install, program, and troubleshoot
your module. This manual:
You must be able to program and operate a ControlNet product and ControlNet
or Ethernet network to make efficient use of a FLEX I/O module.
In this manual, we refer to the:
• 1794-IF8IH and 1794-IF8IHNFXT as the input modules
• 1794-OF8IH as the output module
Related Documentation
The following documents contain additional information concerning
Rockwell Automation® office or distributor.
The following conventions are used throughout this manual:
in this Manual
Information on wiring and installing the 1794-IF8IH HART input module.
Information on wiring and installing the 1794-OF8IH HART output module.
Information on wiring and installing the 1794-IF8IHNFXT HART XT input module.
A description and overview of the 1794 and 1797 series FLEX I/O modules
compatible control platforms, and overview of how to specify a FLEX I/O system.
Web updates for FLEX I/O and FLEX EX I/O DTM libraries.
More information on proper wiring and grounding techniques.
.A glossary of industrial automation terms and abbreviations.
• Bulleted lists such as this one provide information, not procedural steps.
• Numbered lists provide steps or hierarchical information.
• Italic type is used for emphasis.
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FLEX I/O Isolated Input/Output HART Analog Modules User Manual
Notes:
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Summary of Changes
This manual contains new and updated information. Changes throughout this
revision are marked by change bars, as shown to the right of this paragraph.
New and Updated
Information
This table contains the changes made to this revision.
TopicPage
Corrected wiring diagram35
Corrected wiring instructions36
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Notes:
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Chapter
IMPORTANT
IMPORTANT
IMPORTANT
1
About the FLEX I/O HART Analog Modules
Overview
This chapter describes the FLEX I/O Highway Addressable Remote Transducer
(HART) analog modules and what you must know and do before you begin to
use them.
Read this chapter to familiarize yourself with the HART analog modules.
TopicPage
What FLEX I/O Analog Modules Do13
Communicate with Programmable Controllers14
Use Alarms on the Input Modules15
Use the HART Capabilities17
HART Implementation Overview18
Chapter Summary18
To use all features of these modules it must be used with the
1794-ACN(R)15 with version 5.001 firmware or later, or the
1794-AENT with firmware revision 4.002 and later, or the
1794-AENTR with firmware version 1.011 and later.
For more information about using these modules with 1794-ACN(R)15
with firmware revision 5.001 and later, see 1794-RN071
.
Studio 5000 Logix Designer version 24 includes a full profile for
1794-IF8IHNFXT module. You cannot use the 1794-IF8IH profile to
configure the 1794-IF8IHNFXT module.
See Use the 1794-IF8IHNFXT with the Generic and Thin Profiles on
page 153 if you are using RSLogix 5000 version 23 or earlier.
The Studio 5000 Logix Designer application is the re-branding of the
RSLogix 5000 application.
What FLEX I/O Analog
The FLEX I/O HART input and output modules must be used in a ControlNet
or EtherNet/IP network.
Modules Do
The 1794-IF8IH module accepts up to eight analog inputs. The inputs are
isolated and will accept current in either of the following two ranges: 4…20 mA
or 0…20 mA. The default input range is 0…20 mA. The inputs have both fixed
hardware filters and selectable firmware digital filters.
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The 1794-IF8IHNFXT module supports 0…20 mA and 4…20 mA ranges, with
a default input range of 0…20 mA. It has seven selectable input filters and seven
input data formats. It provides support for loop alarm, which detects gross signal
errors such as open and short circuit. It has programmable user alarms (high, low,
remote high high, and remote low low). The module has a HART modem per
channel. It is compliant with HART versions 5, 6, and 7, except for multi-drop
support.
The 1794-OF8IH module provides as many as eight (8) analog outputs. The
outputs are isolated and will provide current in either of the following two
ranges: 4…20 mA or 0…20 mA. The default output range is 0…20 mA.
Each module offers:
• full functionality without switches or jumpers.
• multiple data ranges that can be independently programmed for each
• lead breakage detection.
• overrange/underrange alarms.
• remote transmitter alarm.
channel.
Communicate with
Programmable Controllers
Data connections are established between the FLEX I/O module and an
Allen-Bradley® programmable controller (PLC) to transfer information between
the two at a scheduled rate.
Input module information is then automatically made available in the PLC data
table through the data connection. Reciprocally, output data information
determined by the PLC program is also automatically transferred from the PLC
data table to the output module through the data connection.
In addition, when the data connection is originally established, configuration
information for the module is automatically transferred to it via the network.
Events Following Powerup
You must apply +24V DC power to your FLEX I/O analog I/O modules. The
following sequence of events occurs after power has initially been applied to your
module:
1. The module status indicator will blink red until a connection is established
and a valid configuration is passed to the module.
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Module type
Removable label
Keyswitch
(indicator is at #3)
Power On indicator
Input designators
44811
2. After the diagnostic check, module configuration information, selected by
the user and downloaded over the network, is applied by the module. For
more information on configuration options, refer to Configurable FLEX
I/O Analog Module Features on page 19.
3. Following the module configuration download for the 1794-IF8IH and
1794-IF8IHNFXT modules, the module begins producing runtime data
for the PLC processor.
Following the module configuration download for the 1794-OF8IH
module, the module applies configuration data to output channels.
4. If any diagnostics or alarms are generated during normal module
operation, the data is returned to the PLC processor.
Physical Features of
Your Module
The module label identifies the key-in position, wiring, and module type. Use the
removable label to note individual designations per your application.
Indicators
Indicators are provided to identify input or output fault conditions, and to show
when power is applied to the module. For example, the 1794-IF8IH module is
shown below.
8 CH HART ISOLATED ANALOG INPUT
IN1IN0IN2IN3IN4
IN5
1794-IF8IH
IN6IN7
3
PWR
Use Alarms on the Input
Modules
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The 1794-IF8IH and 1794-IF8IHNFXT FLEX I/O modules are capable of
generating four alarms:
• Low Alarm
• High Alarm
•Remote Fault
•Local Fault
FLEX I/O Isolated Input/Output HART Analog Modules User Manual
IMPORTANT
These alarm conditions are described in general terms and as they relate to bits on
the FLEX I/O module on the following pages.
Low Alarm
The low alarm notifies you when module input signal moves below the
configured low alarm trigger point. If the input signal falls below 0% (4 mA), a
Low Alarm is generated.
High Alarm
The high alarm works converse to the low alarm. This feature notifies you when
the input signal falls above the configured high alarm trigger point. If the input
signal falls above 0% (4 mA), an Underrange Alarm is generated.
Remote Fault Alarm
The remote fault alarm is intended for use with remote transmitter loops.
For example, the remote transmitter may be measuring temperature and
converting it to a standard mA signal. In such a loop, though, the input module
cannot determine the state of the loop on the far side of the transmitter.
However, the remote transmitter may be capable of diagnosing a problem in the
remote loop and signal the input module local loop with a preprogrammed
out-of-range (high or low) value.
The Fault Enable bit allows the 1794-IF8IH and 1794-IF8IHNFXT modules to
work with transmitters like the one described.
Once the alarm is issued, it remains active as long as the input signal
value remains above or below the programmed value.
Use Remote Fault Alarm to Determine High-High or Low-Low Alarm Levels
If you do not have a remote transmitter in your loop, this alarm can also be used
to program a high-high or low-low alarm level between the levels, which actuate
the overrange or underrange alarms and the high or low local fault alarms.
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IMPORTANT
Programming the Remote Fault Alarm
For the remote fault alarm, you must program the threshold in 0.1 mA steps at
any level on the high or low end of input signal range. The remote fault alarm
activates if your I/O module receives input signal values of:
• 100.63…111.88% (20.1…21.9 mA) on the high end of input signal range
or
• -0.63…-11.88% (3.9…2.1 mA) on the low end of input signal range.
Local Fault Alarm
The local fault alarm notifies you when the loop to the transmitter or field device
(if no transmitter is used) is open or shorted.
Use the HART Capabilities
Once the alarm is issued, it remains active as long as the input signal
value remains in the programmed range.
• 112.50% (22 mA) or higher on the high end of input signal range.
This value indicates a short in the loop.
or
• -12.50% (2 mA) or lower on the low end of input signal range.
This value indicates an open wire condition in the loop.
The remote fault and local fault alarms are issued with the same bit whether the
cause is an under or overrange. Monitor the overrange and underrange bits in
your programming software to determine if the problem is a high current or low
current.
Before using the HART capabilities, be sure that:
• the I/O module and the associated field device are working properly in the
analog 4…20 mA mode.
• the I/O module is configured for 4…20 mA range.
• the field device is HART capable.
• no multiple HART field device is connected to each channel.
• input filtering is set to a valid (defined) value.
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FLEX I/O Isolated Input/Output HART Analog Modules User Manual
Processor
User program
AdapterFLEX I/O
HART
module
HART
Field Device
Command
Response
for example, HART
Command 3)
Flexbus
4…20 mA with
HART signal
HART Implementation
Overview
The FLEX I/O HART modules act as intelligent HART multiplexers. Basically,
the module learns which HART devices are attached to its channels and then
routes HART messages, as appropriate, between the HART field devices and the
Flexbus. Since the HART modules act as intelligent HART multiplexers, HART
commands can be issued to the HART modules themselves.
Communication on the Flexbus occurs between the adapter and the HART
module. The adapter converts these messages to the appropriate network format
for communication with the controlling processor. The controlling processor gets
its command from the user program, storing the responses in its memory.
Chapter Summary
In this chapter, you learned about FLEX I/O analog I/O modules and HART
module capabilities. Read the next chapter to learn about configurable features
on your module.
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Chapter
IMPORTANT
Configurable FLEX I/O Analog Module
Features
2
Overview
Read this chapter to familiarize yourself with configurable features on the input
and output analog modules.
TopicPage
Select Your Analog Input Module Operating Features20
Select Your Analog Output Module Operating Features21
Understand Image Table Mapping and Bit/Word Descriptions24
Chapter Summary25
HART configurable features described in this chapter include the following
1794-IF8IH and 1794-IF8IHNFXT
Input Modules
Fault ModeOutput Enable
High Low Error LevelModule Fault State Mode
Input Filter CutoffLocal Fault Mode
Data FormatData Format
1794-OF8IH Output Module
Global Reset
Analog Fault State
Latch Retry Mode
Fault Alarm
You must use the I/O configuration portion of your PLC
programming software to select and configure these features
for 1794-IF8IH and 1794-OF8IH modules. This manual
assumes familiarity with the programming software. A brief
description of each module feature is provided here.
To learn more about configuration for the 1794-IF8IH and
1794-OF8IH modules, see the following:
Configuration on page 39
Use the 1794-IF8IH Module with the Generic Profile on page 137
Use the 1794-OF8IH Module with the Generic Profile on page 177
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IMPORTANT
IMPORTANT
IMPORTANT
Configuration for the 1794-IF8IHNFXT module is done through
Logix Designer software version 24. See Edit Your 1794-IF8IHNFXT
Configuration with Studio 5000 Logix Designer (Full Profile) on page 90.
See Use the 1794-IF8IHNFXT with the Generic and Thin Profiles on page
153 if you are using RSLogix 5000® version 23 or earlier.
Select Your Analog Input
Module Operating Features
All features of the 1794-IF8IH and the 1794-IF8IHNFXT analog input
modules are independently configurable.
The default selection value for all parameters is 0.
Fault Enable
Your input modules are capable of indicating various fault conditions, depending
on the input signal value. Use the Fault Enable feature to enable or disable two
alarms:
• Remote Fault Alarm
•Local Fault Mode
Use your programming software to set the Fault Enable bit to 0 to disable these
alarms. Set the bit to 1 to enable them.
Fault Enable will only enable or disable the Remote and
Local Fault alarms. It does not affect the Underrange and
Overrange alarms. They are always active.
For more information, see Remote Fault Alarm
Alarm on page 17.
Sample Filter Frequency Rates
Six available input filter settings for the 1794-IF8IH module and seven input
filter settings for the 1794-IF8IHNFXT module allow you to choose the best
rolloff frequency for input channels on your I/O module. When choosing a filter,
remember that time filter selection affects your input signal’s accuracy.
For example, if you choose the highest frequency of 470 Hz (filter 0) for the
1794-IF8IH module, signal noise is more likely to affect the reading, but the
slowest frequency of 4.17 Hz (filter 5) provides the most accurate signal due to
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on page 16 and Local Fault
FLEX I/O Isolated Input/Output HART Analog Modules User Manual
IMPORTANT
incoming noise filtering. It is recommended that you use 62 Hz when HART is
enabled to get more accurate signals due to incoming noise.
See the Input Filter Frequency table to decide which input filter to use in your
FLEX I/O analog I/O application:
Input Filter Frequency for the 1794-IF8IH Module
01234567
470 Hz62 Hz19.6 Hz16.7 Hz10 Hz4.17 Hzn/an/a
Input Filter Frequency for the 1794-IF8IHNFNXT Module
01234567
242 Hz123 Hz62 Hz19.6 Hz16.7 Hz10 Hz4.17 Hzn/a
(1)
To configure input filter frequency and other module features for 1794-IF8IHNFXT module in Studio 5000 Logix
Designer see 1794-IF8IHNFXT Configuration Data Table on page 43
(1)
.
Choose the best input filter cutoff in your programming software.
Data Formats
You must choose a module data format in your user program. Six data formats are
available for the 1794-IF8IH module, and seven data formats for the
1794-IF8IHNFXT module.
Default format is 0
The data format selected interprets input readings and returns them to the PLC.
See the Data Format (Configuration Words 2, 3 – bits 0…3, 4…7, 8…11, 12…15)
on page 49 for Data Format tables and a more detailed description of data
formats for the 1794-IF8IH and 1794-IF8IHNFXT modules.
…20 mA.
Select Your Analog Output
Module Operating Features
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To configure data formats and other module features for 1794-IF8IHNFXT
module in Logix Designer, see 1794-IF8IHNFXT Channel Data Formats on
page 51.
All features of the 1794-OF8IH analog output module are independently
configurable.
The default selection value for all parameters is 0.
FLEX I/O Isolated Input/Output HART Analog Modules User Manual
Local Fault Mode
The Local Fault Mode can be programmed to determine how the module
responds to communications faults and internal module faults.
When setting the Local Fault Mode feature in your programming software, set
this feature’s bit to 0 to use the analog fault state or digital fault state only if a
communications fault occurs. Set the bit to 1 to use the Analog Fault state or
Digital Fault state if any fault occurs.
Analog fault state and digital fault state determine how the module reacts to
faults when a channel is used in analog mode or digital mode, respectively.
Latch Mode
Latch Mode determines channel operation under wire-off or lead-break fault
conditions. This feature is available for each channel. Channel detection occurs
on a continuous basis. If a fault is detected, the channel fault alarm is set.
If Latch mode is enabled when a fault occurs, the fault will remain latched in its
fault state until a Global Reset is issued. If Latch mode is disabled when a fault
occurs, the channel reports a fault until the fault is corrected. Global Reset is not
necessary if Latch mode is disabled.
When using your programming software, set the Latch mode bit to 0 to disable
the feature. Set the bit to 1 to enable it.
Global Reset
Global Reset works in conjunction with Latch mode during fault conditions. If
Latch mode is enabled and a fault condition occurs, the channel operating with a
fault remains in this condition (with analog or digital fault state implied) until a
Global Reset is issued. The Global Reset feature resets all outputs of a particular
channel group to accept normal system output data.
The Global Reset feature is an edge triggered signal. Use your programming
software to set the Global Reset bit to 1 for normal operation. Resetting of
outputs occurs during the 1...0 transition.
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Diagnostic Data error 11
= data out of range
Diagnostic Data error 11
= data out of range
04812162024
Output mA
Datatable
20.000
16.000
12.000
8.000
4.000
0.000
-4.000
Data Format
You must choose a module data format in your user program. See 1794-OF8IH
Data Formats on page 77 for an explanation of each bit. Data Formats 2, 5, 6, 8, 9,
10, 11, 12, 13 and 15 are not assigned.
When choosing a data format, remember the following:
• If an unassigned Analog Data Format is selected, the module sets
Diagnostic Data to 2 for configuration failure and puts affected channels
in the corresponding fault state.
• An unconfigured module channel can be assumed to have the default
configuration Analog Data Format 0, 0...20 mA and Analog Mode Fault
State minimum range. If a non-assigned format is selected, then the
diagnostic 2 for configuration failure is set and the module channel goes to
the default fault state minimum range.
• If on the other hand, the configuration had been changed, from the
default, and then it was changed again to a non-assigned format, then the
diagnostic bit 2 for configuration failure is set and the module goes to the
fault state for the last valid configuration.
• Formats 13 and 14 are 2’s complement data formats, and require data to
the module in that form.
• Range: 0…15
•Default: 0
• Data Table Reference: data format, word 12 and 13, bits 0…3, bits 4…7
If the data is sent to the module, which is out of range, the value will be clipped
and Diagnostic Data will be set to 11 data out of range.
Example of Analog Format 14 and Data Clipping Performance.
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For data format tables and a more detailed description of the data formats for the
1794-OF8IH module, see Data Format (Configuration Words 2, 3 – bits 0…3,
4…7, 8…10, 12…15) on page 76.
Fault Alarm
Fault Alarm selects whether the channel fault detection is enabled or disabled.
There is a 100 Hz (10 ms) filter for wire off or lead break detection.
Use your programming software to set the Fault Alarm. Set the feature bit to 0 to
disable the alarm. Set the bit to 1 to enable wire off/lead break fault detection.
Understand Image Table
All Allen-Bradley FLEX I/O modules have a sixteen word table of Real Time
Data (RTD) to be transferred between the controller and the I/O module. Not
Mapping and Bit/Word
all 16 words need be allocated.
Descriptions
1794-IF8IH Analog Data Table
WordBit
1514131211109876543210
0Channel 0 Input Data
1Channel 1 Input Data
2Channel 2 Input Data
3Channel 3 Input Data
4Channel 4 Input Data
5Channel 5 Input Data
6Channel 6 Input Data
7Channel 7 Input Data
8 H7H6H5H4H3H2H1H0L7L6L5L4L3L2L1L0
9R7 R6 R5R4 R3R2R1R0P7P6P5P4P3P2 P1P0
10ReservedDiagnostic Status
11C7C6C5C4C3C2C1C0F7F6F5F4F3F2F1F0
12X7X6X5X4X3X2X1X0Reserved
Where: Hn: Channel n High Alarm
Ln: Channel n Low Alarm
Pn: Channel n Out Of Range Alarm
Rn: Channel n Second (Remote) Alarm
Fn: Channel n HART Failure
Cn: Channel n HART Current Fault
Xn: Channel n HART Transmitter Present
0: False 1: True
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FLEX I/O Isolated Input/Output HART Analog Modules User Manual
1794-IF8IHNFXT Analog Data Table
WordBit
1514131211109876543210
0Channel 0 Input Data
1Channel 1 Input Data
2Channel 2 Input Data
3Channel 3 Input Data
4Channel 4 Input Data
5Channel 5 Input Data
6Channel 6 Input Data
7Channel 7 Input Data
8H7 H6H5H4H3H2H1H0L7L6 L5 L4 L3L2 L1 L0
9R7 R6R5R4R3R2R1R0P7P6 P5P4P3P2 P1P0
10
11C7C6C5C4C3C2C1C0F7F6F5F4F3F2F1F0
Where: Hn: Channel n High Alarm
(1)
X7
X6X5X4X3X2X1X0Diagnostic Status
Ln: Channel n Low Alarm
Pn: Channel n Out Of Range Alarm
Rn: Channel n Second (Remote) Alarm
Fn: Channel n HART Failure
Cn: Channel n HART Current Fault
Xn: Channel n HART Transmitter Present
0: False 1: True
(1)
When Xn is set, a device is connected and a has a valid device information Data-Set™ available. This bit will clear if the channel is inhibited, the device is removed, or the
device is faulted, and will not be set again until a complete device information set is successfully regathered. Words S:0…S:3 are input data classified as Status Words
but in RSLogix™ generic profile, these words are shown as tags I:8…I:11.
1794-IF8IHNFXT Output Analog Data Table
WordBit
1514131211109876543210
0RRRRRRRRHO7HO6HO5HO4HO3HO2HO1HO0
Where: HOn: Channel n HART Off Dynamic Control bit
0: False 1: True
Chapter Summary
In this chapter, we told you about the FLEX I/O system and the analog I/O
modules, and how they communicate with programmable controllers. Move on
to the next chapter to learn how to install your FLEX I/O analog module.
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Notes:
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Chapter
Install Your FLEX I/O Analog Modules
3
Overview
Before You Install Your
Analog Module
Read this chapter to install the input and output analog modules.
TopicPage
Before You Install Your Analog Module27
Removal and Insertion Under Power27
Install the Module28
Wire the Terminal Base Units34
Connect Wiring to the FLEX I/O HART Analog Modules34
Ground the Module38
Chapter Summary38
Before installing your FLEX I/O analog module:
You Need ToAs Described Under
Verify that the module will be installed in a
suitable enclosure
Position the keyswitch on the terminal baseInstall the Module on page 28
Removal and Insertion Under Power
page 27
on
ATTENTION: These modules do not receive primary operational
power from the backplane. +V and -V DC power must be applied to
your module before installation. If power is not applied, the module
position will appear to the adapter as an empty slot in your chassis.
Removal and Insertion
Under Power
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WARNING: These modules are designed so you can remove and insert
them under power. However, take special care when removing or
inserting these modules in an active process. I/O attached to any
module being removed or inserted can change states due to its
input/output signal changing conditions.
If you insert or remove the terminal base while backplane power is on, an
electrical arc can occur. This could cause an explosion in hazardous
location installations.
Be sure that power is removed or the area is nonhazardous before
proceeding.
FLEX I/O Isolated Input/Output HART Analog Modules User Manual
WARNING: When used in a class I, division 2, hazardous location,
this equipment must be mounted in a suitable enclosure with proper
wiring method that complies with the governing electrical codes.
Install the Module
Installation of the module consists of the following:
•Mounting the terminal base unit.
• Installing the analog I/O module into the terminal base unit.
• Installing the connecting wiring to the terminal base unit.
If you are installing your module into a terminal base unit that is already installed,
proceed to page 32.
ATTENTION: Do not use the unused terminals on the terminal base
unit. Using the terminals as supporting terminals can result in damage
to modules and/or unintended operation of your system.
Mount on a DIN Rail
ATTENTION: Do not remove or replace a terminal base unit when
power is applied. Interruption of the Flexbus can result in unintended
operation or machine motion.
Install the Terminal Base Unit
1. Remove the cover plug in the male connector of the unit to which you are
connecting this terminal base unit.
2. Check to make sure that the 16 pins in the male connector on the adjacent
device are straight and in line so that the mating female connector on this
terminal base unit will mate correctly.
3. Verify that the female Flexbus connector is fully retracted into the base
unit.
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A
A
41106
41107
4. Position the terminal base at a slight angle and hooked over the top of the
35 x 7.5 mm DIN rail A
(Allen-Bradley part number 199-DR1)
5. Slide the terminal base over tight against the adapter (or proceeding
terminal base). Make sure the hook on the terminal base slides under the
edge of the adapter (or proceeding terminal base) and the Flexbus
connector is fully retracted.
ATTENTION: Do not force the terminal base into the adjacent
modules. Forcing the units together can bend or break the hook and
allow the units to separate and break communication over the
backplane.
6. Rotate the terminal base onto the DIN rail with the top of the rail hooked
under the lip on the rear of the terminal base.
Use caution to make sure that the female Flexbus connector does not
strike any of the pins in the mating male connector.
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41108
41109
7. Press down on the terminal base unit to lock the terminal base on the DIN
rail. If the terminal base does not lock into place, use a screwdriver or
similar device to open the locking tab, press down on the terminal base
until flush with the DIN rail and release the locking tab to lock the base
in place.
Gently push the Flexbus connector into the side of the adapter (or
proceeding terminal base) to complete the backplane connection.
8. For specific wiring information, see the installation instructions for the
module you are installing in this terminal base unit.
Terminal assignments are also given later in this chapter, see page 34.
9. Repeat the above steps to install the next terminal base unit.
Be sure the Flexbus connector cover on the last terminal base unit is
in place.
Mount on a Panel or Wall
Installation of a FLEX I/O system on a wall or panel consists of:
• laying out the drilling points on the wall or panel.
• drilling the pilot holes for the mounting screws.
• mounting the adapter mounting plate.
• installing the terminal base units and securing them to the wall or panel.
If you are installing your module into a terminal base unit that is already installed,
proceed to Mount the Analog Modules on the Terminal Base Unit on page 32.
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4
1
2
(35.5)
1.4
41547
3
35.5
(1.4)
15.6
(0.61)
58.5
(2.3)
40.5
(1.6)
8 (0.3)
35.5
(1.4)
58.5
(2.3)
35.5
(1.4)
0.83 (21)
50
(2.0)
Measurements are in mm (in.)
40871
TIP
Use the mounting kit Cat. No. 1794-NM1 for panel/wall mounting.
DescriptionDescription
1Mounting plate for adapter3Terminal base unit (not included)
1. Lay out the required points on the wall/panel as shown in the drilling
dimension drawing.
Cable is either 292.1 mm (11.5 in.) or 901.0 mm (35.5 in.) from upper
connector — depending if you use 0.3 m (1 ft) or 0.91 m (3 ft) cable.
ATTENTION: Be careful of metal chips when drilling cable mounting
holes. Do not drill holes above a system that has any modules
installed.
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IMPORTANT
2. Drill the necessary holes for the #6 self-tapping mounting screws.
3. Mount the mounting plate for the adapter module using two #6
4. Hold the adapter at a slight angle and engage the top of the mounting plate
5. Press the adapter down flush with the panel until the locking lever locks.
6. Position the terminal base unit up against the adapter and push the female
7. Secure to the wall with two #6 self-tapping screws.
self-tapping screws (18 included for mounting up to 8 modules and the
adapter).
Verify that the mounting plate is properly grounded to the
panel. See Industrial Automation Wiring and Grounding
Guidelines, publication 1770-4.1
.
in the indention on the rear of the adapter module.
bus connector into the adapter.
8. Repeat for each remaining terminal base unit.
Mount the Analog Modules on the Terminal Base Unit
The HART analog input and output modules mounts on a 1794-TB3 or
1794-TB3S terminal base unit.
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3
2
4
5
6
1
8
7
Label here
40231
or under here
1. Rotate keyswitch on terminal base unit clockwise to position 3 for the
1794-IF8IH/1794-IF8IHNFXT modules or position 4 for the
1794-OF8IH as required for each type of module.
Do not change the position of the keyswitch after wiring the terminal
base unit.
DescriptionDescription
1Flexbus connector5Base unit
2Latching mechanism6Alignment groove
3Keyswitch7Alignment bar
4Cap plug8Module
2. Verify that the Flexbus connector is pushed all the way to the left to
connect with the neighboring terminal base/adapter.
You cannot install the module unless the connector is fully extended.
3. Make sure the pins on the bottom of the module are straight so they will
align properly with the connector in the terminal base unit.
4. Position the module with its alignment bar aligned with the groove on the
terminal base.
5. Press firmly and evenly to seat the module in the terminal base unit.
The module is seated when the latching mechanism is locked into the
module.
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41307
IMPORTANT
IMPORTANT
6. Remove cap plug and attach another terminal base unit to the right of this
terminal base unit if required.
Make sure the last terminal base has the cap plug in place.
The adapter is capable of addressing eight modules. Do not
exceed a maximum of eight terminal base units in your system.
Wire the Terminal Base
Wiring the FLEX I/O HART analog input modules is done using the 1794-TB3
or the 1794-TB3S terminal base unit.
Units
Connect Wiring to the FLEX
I/O HART Analog Modules
Each 1794-IF8IH and IF8IHNFXT input can be operated from an analog field
device signal, and each 1794-OF8IH output channel can operate an analog field
device.
ATTENTION: The FLEX I/O analog modules do not receive primary
operational power from the backplane. +24V DC power must be
applied to your module before operation. If power is not applied,
the module position will appear to the adapter as an empty slot in
your chassis. If the adapter does not recognize your module after
installation is completed, cycle power to the adapter.
When interconnecting several lines, you must consider the total
accumulated power.
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NOTE: Loop power is not provided for the inputs. Each input requires an external power source, as illustrated in the following diagram.
Connections for the 1794-IF8IH and 1794-IF8IHNFXT HART Analog Input
Modules on a 1794-TB3S Terminal Base Unit
+V
Flexbus
Bus
17V
uC
22 Ω
1032547698112131014151
91 Ω
81910212
CH-0CH-2CH-4CH-6
CH-1CH-3CH-5CH-7
8292031323332232425262726171
647484940515041424344454435363738393
-V
+
Sig
-
4...20 mA
Xmit
I
P
4...20 mA
Xmit
I
A
P
40072
0...15
16...33
B
34...51
C
44781
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0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
33
2417
05948474
83
73
63
34
51
16
44319
AC or DC
Four-wire
Current
Transmitter
Row A
Row B
Row C
Current
Input
Current
Input
Current
Input
1794-TB3S shown
DC only
Three-wire
Current
Transmitter
DC only
Two-wire
Current
Transmitter
Label placed at top of wiring area
Row C
Row B
Row A
18
192021
22 23
25
26
27
28
29
30 31
32
3539
40
41
42
43
44
45
46
44319
1794-TB3S shown
For Two-wire Transmitter Devices:
1. Connect the individual input wiring to terminal pairs (0/1) (2/3) (4/5)
(6/7) (8/9), (10/11), (12/13), (14/15).
2. Connect +V DC power to terminal 34 on the 34…51 row (C).
3. Connect -V to terminal 16 on the 16…33 row (B).
4. If continuing power to the next terminal base unit, connect a jumper from
terminal 51 (+V DC) on this base unit to +V DC power terminal on the
next terminal base unit.
5. If continuing common to the next terminal base unit, connect a jumper
from terminal 33 (-V common) on this base unit to the -V common
terminal on the next terminal base unit.
ATTENTION: Do not use the unused terminals on the terminal
base unit. Using these terminals as supporting terminals can result
in damage to the module and/or unintended operation of
your system.
36Rockwell Automation Publication 1794-UM065D-EN-P - April 2020
FLEXbus
0
16
34
1
17
35
2
18
36
3
19
37
4
20
38
5
21
39
6
22
40
7
23
41
8
24
42
9
25
43
10
26
44
11
27
45
12
28
46
13
29
47
14
30
48
15
31
49
32
50
33
51
44319x
Row A
Row B
Row C
Row B
Row C
Row A
1794-TB3S shown
Label placed at top of wiring area
ActuatorActuator
Actuator
FLEX I/O Isolated Input/Output HART Analog Modules User Manual
Connections for the 1794-OF8IH HART Analog Output Module on a
+V
-V
Power
supply
I
F
4...20 mA
Actuator
4...20 mA
valve
41441
1794-TB3 or 1794-TB3S Terminal Base Unit
250 Ω
21.6V
Bus
uC
HART
Modem
45 Ω
1794-OF8IH Module
+
-
CH-0
CH-1CH-2CH-3CH-4CH-5CH-6CH-7
1032547698112131014151
A
0...15
81910212
-Vin-V
C O M M O N S
8292031323332232425262726171
B
16...33
647484940515041424344454435363738393
34...51
C
+Vin+V
44782
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44398
Shield-terminating feed through
Bus bar
1. Connect the individual input wiring to terminal pairs (0/1), (2/3), (4/5),
2. Connect +V DC power to terminal 34 on the 34...51 row (C).
3. Connect -V to terminal 35 on the 34...51 row (C).
4. If continuing power to the next terminal base unit, connect a jumper from
5. If continuing common to the next terminal base unit, connect a jumper
ATTENTION: Do not use the unused terminals on the terminal
base unit. Using these terminals as supporting terminals can result
in damage to the module and/or unintended operation of your
system.
(6/7), (8/9), (10/11), (12/13), (14/15).
terminal 50 (+V DC) on this base unit to +V DC power terminal on the
next terminal base unit.
from terminal 51 (-V common) on this base unit to the -V common
terminal on the next terminal base unit.
Ground the Module
Chapter Summary
All I/O wiring must use shielded wire. Shields must be terminated external to the
module, such as bus bars and shield-terminating feedthroughs.
8 CH HART ISOLATED ANALOG INPUT
IN0 IN1 IN2 IN3
IN4 IN5 IN6 IN7
1794-xx8iH
I/O
3
PWR
In this chapter, we told you how to install your input module in an existing
programmable controller system and how to wire to the terminal base units.
Go to the next chapter to learn about input, output, and configuration files for
HART analog I/O modules on ControlNet and EtherNet/IP networks.
38Rockwell Automation Publication 1794-UM065D-EN-P - April 2020
Configuration
IMPORTANT
IMPORTANT
Chapter
4
Overview
This section provides descriptions of the different configuration parameters for
your FLEX I/O HART modules.
Configuring the 1794-IF8IH and 1794-OF8IH modules require
RSLogix 5000 version 17 or later. See the following sections for
configuring your modules:
• Use the 1794-IF8IH Module with the Generic Profile on page 137
• Use the 1794-OF8IH Module with the Generic Profile on page 177
Configuring the 1794-IF8IHNFXT module requires Studio 5000 Logix
Designer
Configuration with Studio 5000 Logix Designer (Full Profile) on page 90
for information on how to configure the 1794-IF8IHNFXT module with
Studio 5000 Logix Designer.
If you are using RSLogix 5000 version 23 or earlier, you can use the thin
and generic profiles to configure your module, see Use the 1794-
IF8IHNFXT with the Generic and Thin Profiles on page 153.
(1) The Studio 5000 Logix Designer application is the re-branding of RSLogix 5000 software.
See the table for a list of where to find specific information in this chapter.
TopicPage
(1)
version 24 or later. See Edit Your 1794-IF8IHNFXT
Data Transfer Types39
Primary Input Data (RTD Input Data) for 1794-IF8IH and 1794-IF8IHNFXT57
Secondary Input Data (Cyclic EDT Input Data) for 1794-IF8IH and 1794IF8IHNFXT
RTD Output Data for 1794-IF8IHNFXT69
Module Configuration for the 1794-OF8IH69
Primary Input Data (RTD Output Data) for the 1794-OF8IH82
Secondary Input Data (Cyclic EDT Input Data) for 1794-OF8IH87
Interpret the Status Indicators89
Edit Your 1794-IF8IHNFXT Configuration with Studio 5000 Logix Designer (Full
Profile)
Chapter Summary106
Data Transfer Types
39Rockwell Automation Publication 1794-UM065D-EN-P - April 2020
The modules make use of three data transfer modes that will be supported by the
FLEX I/O Adapter.
64
90
FLEX I/O Isolated Input/Output HART Analog Modules User Manual
The first mode is traditional real-time data transfer called Cyclic Data Transfer
(CDT). This class 1 connection continuously transfers 16 words maximum,
composed of Input, Output, and Configuration registers. CDT will be used for
standard Analog data transfers.
The second mode of data transfer uses the Cyclic EDT mode. Cyclic EDT will be
used for continuous Class 1 transfer of HART data. This includes the first four
dynamic HART Data variables, along with standard HART status information.
The third mode of data transfer uses EDT for HART pass-through Class 3
Messages. HART pass-through messages can be initiated from a number of
sources, and are non-periodic. This allows the HART pass-through messages
from the HART Foundation Server, and other third-party sources.
1794-IF8IH and 1794-IF8IHNFXT I/O Profiles
All Allen-Bradley FLEX I/O modules have a 16 word table of Real Time Data
(RTD) to be transferred between the controller and the I/O module. Not all 16
words need be allocated. The 1794-IF8IH and 1794-IF8IHNFXT modules have
the following RTD IO Profile:
1794-IF8IH RTD I/O Profile
RTD IndexAssembly/IndexAssembly
RTD 0MSWModule Status Word
RTD 1EDT Read WordEDT Read Word
RTD 2…9I:0…I:7RTD Input Data
RTD 10…14S:0…14RTD Status Data
RTD 15EDT Write WordEDT Write Word
In addition to the RTD, the module uses EDT for Configuration and HART
data. The 1794-IF8IH and 1794-IF8IHNFXT modules have the following EDT
IO Profiles:
1794-IF8IH EDT I/O Profile
Number of WordEDT Assembly
42EDT Configuration Data
98Cyclic EDT HART Input Data (Accessed in eight 24 byte Assemblies)
48EDT Output Pass-Through message request buffer A
1794-IF8IHNFXT EDT IO Profile
Number of WordEDT Assembly
106EDT Configuration Data
98Cyclic EDT HART Input Data (Accessed in eight 24 Assemblies)
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Configuration Parameters
The configuration parameters for 1794-IF8IH module are shown in the
following table. These are normal module configuration items and are sent to the
for 1794-IF8IH
module. Configuration is located at EDT assembly 37. The last row of the
following table gives a brief explanation of each configuration parameter bit.
1794-IF8IH Configuration Data Table
WordBit
1514131211109876543 210
0 R R F7F6F5F4
1DH7DH6DH5DH4DH3DH2DH1DH0
2CH 3 FormatCH 2 FormatCH 1 FormatCH 0 Format
3CH 7 FormatCH 6 FormatCH 5 FormatCH 4 Format
4CH1 HART Current RatioFLTR1CH0 HART Current RatioFLTR0
5CH3 HART Current RatioFLTR3CH2 HART Current RatioFLTR2
6CH5 HART Current RatioFLTR5CH4 HART Current RatioFLTR4
7CH7 HART Current RatioFLTR7CH6 HART Current RatioFLTR6
8Reserved
9CH0 High Alarm threshold
10CH0 Low Alarm threshold
11CH0 Remote High High Alarm Limit
12CH0 Remote Low Low Alarm Limit
13…16Words 9…12 for Channel 1
17…20Words 9…12 for Channel 2
21…24Words 9…12 for Channel 3
25…28Words 9…12 for Channel 4
29…32Words 9…12 for Channel 5
33…36Words 9…12 for Channel 6
37…40Words 9…12 for Channel 7
41ReservedC7C6C5C4C3C2C1C0
Where:BOA = Byte Order Group A
(1) Not shown or used in the RSLogix 5000 software.
(2) Reserved data may not be shown in certain controller software.
BOB = Byte Order Group B
Note: Byte order group A and B values must match each other. See the table
CHn HART Current Ratio = HART current ratio limiti on Channel n. Valid values are 0, or 5…31 percent of full scale. A value of 0 disables this feature. See table
Current Ratio on page 63 for more information.
DHn = Disable HART communication on Channel n.
0: HART communications enabled; 1: HART communications disabled.
Cn = HART Data Publishing Disable for Channel n.
0: HART Data Publishing Disable enabled; 1: HART Data Publishing Disable disabled.
R = Reserved.
CH N format = Data format for Channel n. See table
1794-IF8IH Channel Digital Filter on page 48.
1794-IF8IH Channel Data Formats on page 50.
BOB
(1)
RRF3F2F1F0
Reserved
Byte Order on page 44.
(2)
(1)
BOA
1794-IF8IH HART
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After looking at the configuration tables, see also Configuration Parameter
Descriptions for 1794-IF8IH and 1794-IF8IHNFXT on page 44 for a detailed
description of the configuration parameter bits.
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Configuration Parameters
The last row of the following table gives a brief explanation of each configuration
bit. See also, Configuration Parameter Descriptions for 1794-IF8IH and 1794-
for 1794-IF8IHNFXT
1794-IF8IHNFXT Configuration Data Table
WordBit
0R R F7F6F5F4
1DH7DH6DH5DH4DH3DH2DH1DH0Reserved
2CH 3 FormatCH 2 FormatCH 1 FormatCH 0 Format
3CH 7 FormatCH 6 FormatCH 5 FormatCH 4 Format
4HART_Ilimit_CH1FLTR1HART_Ilimit_CH0FLTR0
5HART_Ilimit_CH3FLTR3HART_Ilimit_CH2FLTR2
6HART_Ilimit_CH5FLTR5HART_Ilimit_CH4FLTR4
7HART_Ilimit_CH7FLTR7HART_Ilimit_CH6FLTR6
8CH0 High Alarm Threshold
9CH0 Low Alarm Threshold
10CH0 Remote High High Alarm Limit
11CH0 Remote Low Low Alarm Limit
12CH0 PvDampingValue (32 bit, Floating Point, LowWord)
13CH0 PvDampingValue (32-bit Floating Point, HighWord)
14CH0 PvUpperRange (32-bit Floating Point, LowWord)
15CH0 PvUpperRange (32-bit Floating Point, HighWord)
16CH0 PvLowerRange (32-bit Floating Point, LowWord)
17CH0 PvLowerRange (32-bit Floating Point, HighWord)
18ReservedCH0 PV Range Units Code
19Unused
20…31Words 8…19 for channel 1
32…43Words 8…19 for channel 2
44…55Words 8…19 for channel 3
56…67Words 8…19 for channel 4
68…79Words 8…19 for channel 5
80…91Words 8…19 for channel 6
92…103Words 8…19 for channel 7
104ReservedC7C6C5C4C3C2C1C0
105ER7ER6ER5ER4ER3ER2ER1ER0ED7ED6ED5ED4ED3ED2ED1ED0
Where:BOA = Byte Order Group A
1514131211109876543210
BOB = Byte Order Group B
Byte order group A and B values must match each other.
Byte Order (Configuration Word 0 – bits 0…1, 8…9) on page 44 for more information.
See
FLTRn = Channel n Digital Filter. See table
Fn = Fault mode Channel n. 0: Local / Remote faults disabled; 1: Enabled.
HART_Ilimit_CHn = HART Loop Tolerance Error Limit for Channel n. Defines comparison limit for HART current loop to ADC compare.
Valid values are 0, or from 5 to 31 percent of full scale. A value of zero disables this feature. Full scale is defined as the difference between the normal high scale and the normal
low.
IF8IHNFXT on page 44, for a more detailed description of the configuration
bits.
(1)
BOB
1794-IF8IH Channel Digital Filter on page 48 and 1794-IF8IHNFXT Channel Digital Filter on page 48.
RRF3F2F1F0
BOA
(1)
Example: 4…20 mA: 20 - 4 = 16. 5% of 16 is 0.8 mA.
Example: 4…20 mA: 20 - 0 = 20. 5% of 20 is 1.0 mA.
DHn = Disable HART communication on Channel n. 0: HART communications enabled; 1: HART communications disabled.
Cn = HART Data Publishing Disable for Channel n. 0: HART Data Publishing Disable enabled; 1: HART Data Publishing Disable disabled.
EDn = Enable HART PV Damping Value for Channel n. 0: True; 1: False.
ERn = Enable HART PV Upper and Lower Range for Channel n. 0: True; 1: False.
R = Reserved.
CH N Format = Data format for Channel n. See table
12…15) on page 49.
CHn PVDampingValue = 32-bit Float (per channel) value used in HART Cmd 34 to set the device PV (primary value) damping value.
CHn PV Range Units Code = 8 bit unsigned (per channel) PV Range Units Code used in HART Command 35. This value specifies the "Units Code" for the Upper and Lower Range
value configuration parameters and also supplies the value for command 44.
This value is required by Command 35 to inform the device what units the Upper and Lower range values being sent in Command 35 are in. Command 35 does not change the PV
units of the device.
Command 44 is automatically sent by the module if the module detects that the PV Units code of the device does not match the parameter in the configuration table.
CHn PvUpperRange = 32-bit Float (per channel) specifies the value for the PV Upper Range value used in HART Cmd 35 to set the device PV Upper Range Value.
CHn PvLowerRange = 32-bit Float (per channel). Specifies the value for the PV Upper Range value used in HART Cmd 35 to set the device PV Upper Range Value.
1794-IF8IHNFXT Channel Data Formats on page 51 and Data Format (Configuration Words 2, 3 – bits 0…3, 4…7, 8…11,
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IMPORTANT
(1) Not shown in RSLogix 5000 software.
Configuration Parameter
Descriptions for 1794-IF8IH
and 1794-IF8IHNFXT
The following sections describe in detail each configuration parameter included
in the tables:
• 1794-IF8IH Configuration Data Table
on page 41
• 1794-IF8IHNFXT Configuration Data Table on page 43
These parameter descriptions apply to both 1794-IF8IH and
1794-IF8IHNFXT modules, unless otherwise specified.
Byte Order (Configuration Word 0 – bits 0…1, 8…9)
This setting selects the byte order of module data. Note: The MSW and EDT
words (Words 0, 1 and 15) of the Primary Input Data Table are not swapped. All
other Primary Input Data and Configuration Data are adjusted according to the
following chart.
Byte Order
Byte Order
Group B
Bit 9Bit 8Bit 1Bit 0Description
0000Little Endian Format (default) — all data entries in true
1010Word Swap — word swap only values requiring more
Byte Order
Group A
Little Endian format
than one word, for example, 32-bit float values.
0101Byte Swap — byte swap all words in data table.
1111Big Endian Format — all data entries in true Big Endian
format.
Byte Order cannot be changed using RSLogix 5000
software. RSLogix 5000 uses the default Byte Swap setting.
The purpose of this parameter is to allow this module to operate properly within
data networks or systems utilizing various byte orders, across all data types (for
example, Boolean data to 32-bit float data). Upon receiving the configuration
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FLEX I/O Isolated Input/Output HART Analog Modules User Manual
IMPORTANT
assembly the module must inspect BYTE ORDER to determine how to interpret
the configuration assembly.
RSLogix 5000 users will never need to configure the Byte Order bits. For
non RSLogix 5000 users, see the 1794-IF8IH Configuration Data Table
page 41 and 1794-IF8IHNFXT Configuration Data Table on page 43 on
how to map the Byte Order bits.
on
Two sets of Byte Order bits are provided since the module will not know at
powerup and configuration reception what Endian format the configuration data
being received is in. No matter what the format, 2-bit sets will always convey
correct information to the module. Both sets must match each other for the
module to accept the configuration and begin processing it for operation. If the
two sets do not match, the module will revert to the last valid configuration (in
case of original startup this would be default configuration) and set module
Diagnostic Status to 2, configuration failure.
Reasoning for this configuration parameter: Within the CIP™ based
Rockwell Automation control system all data is transported and utilized in Little
Endian format. As such the default mode of operation for these modules will be
Little Endian.
Since these modules are HART modules, and HART data is normally provided
in Big Endian format, the module will be responsible for converting any HART
in Big Endian format into Little Endian format.
Examples
In each of the following examples, the module operates internally with little
Endian byte order.
Little Endian Byte Order
If BYTE ORDER indicates Little Endian, utilize the configuration assembly
directly.
Partial Configuration Assembly as Received
Partial Configuration Assembly after BYTE ORDER Inspection and Processing
1Param A Ch2Param B Ch2Param A Ch1Param B Ch1
2Param C CH0 (2nd byte)Param C CH0 (low byte)
3Param C CH0 (high byte)Param C CH0 (3rd byte)
1Param A Ch2Param B Ch2Param A Ch1Param B Ch1
2Param C CH0 (2nd byte)Param C CH0 (low byte)
3Param C CH0 (high byte)Param C CH0 (3rd byte)
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Provide all data to the Primary Data table in Little Endian byte order.
The following two tables are an example of the Primary Input Data, if BYTE
ORDER indicated Little Endian.
Primary Input Data Before BYTE ORDER Processing for Little Endian
1Ch2 Data A (REAL) (2nd byte)Ch2 Data A (REAL) (low byte)
2Ch2 Data A (REAL) (high byte)Ch2 Data A (REAL) (3rd byte)
3Ch2 Data CCh2 Data B
Primary Input Data After BYTE ORDER Processing for Little Endian
1Ch2 Data A (REAL) (2nd byte)Ch2 Data A (REAL) (low byte)
2Ch2 Data A (REAL) (high byte)Ch2 Data A (REAL) (3rd byte)
3Ch2 Data CCh 2 Data B
Word Swap Byte Order
If BYTE ORDER indicates Word Swap, utilize the known structure of the
configuration assembly to reorder multi-word data elements to Little Endian byte
order, for example, word swap FLOATS.
Partial Configuration Assembly as Received
1Param A Ch2Param B Ch2Param A Ch1Param B Ch1
2Param C CH0 (high byte)Param C CH0 (3rd byte)
3Param C CH0 (2nd byte)Param C CH0 (low byte)
Partial Configuration Assembly after BYTE ORDER Inspection and Processing
1Param A Ch2Param B Ch2Param A Ch1Param B Ch1
2Param C CH0 (2nd byte)Param C CH0 (low byte)
3Param C CH0 (high byte)Param C CH0 (3rd byte)
Provide all data to the Primary Data table in Word Swap byte order, except the
MSW and EDT words (Words 0, 1 and 15), these remain in Little Endian byte
order.
The following tables are an example of the Primary Input Data, if BYTE
ORDER indicated Word Swap.
Primary Input Data Before BYTE ORDER Processing for Little Endian
1Ch2 Data A (REAL) (2nd byte)Ch2 Data A (REAL) (low byte)
2Ch2 Data A (REAL) (high byte)Ch2 Data A (REAL) (3rd byte)
3Ch2 Data CCh 2 Data B
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Primary Input Data After BYTE ORDER Processing for Little Endian
1Ch2 Data A (REAL) (high byte)Ch2 Data A (REAL) (3rd byte)
2Ch2 Data A (REAL) (2nd byte)Ch2 Data A (REAL) (low byte)
3Ch2 Data CCh 2 Data B
Fault Mode (Configuration Word 0, bits 2…5, 10…13)
Selects whether the channel fault detection for Local and Remote Alarms is
enabled or disabled. This does not disable High and Low Alarms.
Range: 0=disable, 1=fault detection enabled (remote transmitter loop, wire off
and overload or short circuit)
Default: 0
Digital Filter (Configuration Words 4…7 – bits 0…2, 8…10)
Digital filter for the channel. This parameter affects channel accuracy. See the
following table.
(1) For settings of 6 and 7 the module will return a configuration error and remain in the last properly configured state.
Accuracy vs Filter Cutoff for 1794-IF8IHNFXT
Filter Cutoff76543210 (Default)
Frequency
Word Settingn/a110101100011010001000
(1) Invalid or configuration error.
7
n/a
(1)
(1)
(1)
6
4.17 Hz10 Hz16.7 Hz19.6 Hz62 hz123 Hz242 Hz
543210 (Default)
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Value
(1)
Bits
1098
1794-IF8IH Channel Digital Filter
Digital Filter frequency Decimal
210
470 Hz0000
62 Hz1001
19.6 Hz2010
16.7 Hz3011
10 Hz4100
4.17 Hz5101
Not applicable6110
Not applicable7111
(1) Channel Digital Filters are represented by Words 4…7 (bits 8…10 and 0…2)
in the
1794-IF8IH Configuration Data Table on page 41.
1794-IF8IHNFXT Channel Digital Filter
(1)
Digital Filter frequency Decimal
Value
Bits
1098
210
242 Hz0000
123 Hz1001
62 Hz2010
19.6 Hz3011
16.7 Hz4100
10 Hz5101
4.17 Hz6110
Not applicable7111
(1) Channel Digital Filters for the 1794-IF8IHNFXT module are represented by Words 4…7
(bits 0…2, and 8…10) of the
1794-IF8IHNFXT Configuration Data Table on page 43.
ADC Conversion Rate, Channel Update Time, and Repeatability
The following table shows the channel update time, channel settling time,
repeatability, 50 Hz normal mode rejection, and 60 Hz normal mode rejection
for each A/D conversion rate. The repeatability is based on six-sigma RMS
noise levels.
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Datatable = 10000
input
(
20
)
ADC Conversion Rate Effects for the 1794-IF8IH Module
Data Format (Configuration Words 2, 3 – bits 0…3, 4…7, 8…11,
12…15)
Specifies the module data format. If they are selected, a configuration failure will
be declared. The configuration is not accepted and the last valid configuration
will be used.
Range: 0…15, See the following 1794-IF8IH and 1794-IF8IHNFXT data
format tables.
Default: 0
1794-IF8IH Data Formats
Data
Format
00…20 mA as mA0.1% of
10…20 mA
FormatResolutionInput
as %
(1)
0…20 mA
0.2% of
0…20 mA
Module Data ProcessingData Table Value
Range
0…22 mADatatable = 1000 (input)0…22000
0…22 mA0…11000
(Interpretation)
(0…22.000 mA)
(0…110.00%)
Count per mA/
Resolution
1000/
1.0 µA
500/2.0 µA
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Datatable = 65535
input
(
20
)
Datatable = 10000
input-4
(
16
)
Datatable = 65535
input-4
(
16
)
1794-IF8IH Data Formats
Data
Format
30…20 mA as
44…20 mA as mA0.1% of
54…20 mA as %0.16% of
74…20 mA as
(1) All other formats are invalid.
1794-IF8IH Channel Data Formats
Format
(2)
FormatResolutionInput
unsigned
integer
unsigned
integer
BitsFormat NameSignal RangeUser RangeResolution
15 14 13 12
11 10 98
7654LOHILOHI
(1)
0.03% of
0…20 mA
4…20 mA
4…20 mA
0.03% of
4…20 mA
Module Data ProcessingData Table Value
Range
0…20 mA0…65535
2…22 mADatatable = 1000 (input) 2000…22000
2…22 mA-1250 … +11250
4…20 mA0…65535
(1)
(Interpretation)
(0…20 mA)
(2.000…22.000
mA)
(2’s complement)
(-12.50% …
+112.50%)
(4…20 mA)
Count per mA/
Resolution
3276/
0.3052 µA
1000/
1.0 µA
625/
1.6 µA
4095/
0.2441 µA
3210
000000…20 mA in Milliamps0.0022.000 (0.000 mA)22000 (22.000 mA)1.0 µA
100010…20 mA in % Full Scale0.00 22.00 0 (0%)11000 (110.00%)2.0 µA
300110…20 mA in UINT0.00 20.00 0655350.3052 µA
401004…20 mA in Milliamps2.0022.002000 (2.000 mA)22000 (22.000 mA)1.0 µA
501014…20 mA in % Full Scale2.00 22.00 -1250 (-12.50%)11250 (112.50%)1.6 µA
701114…20 mA in UINT4.00 20.00 0655350.2441 µA
(1) Channel Data Formats for 1794-IF8IH are represented by Words 2 and 3 in the 1794-IF8IH Configuration Data Table on page 41.
(2) All other formats are invalid.
1794-IF8IHNFXT Data Formats
Data
Format
00…20 mA as mA0.0020.00200001.0 A
10…20 mA as %0.0020.00100002.0 A
30…20 mA as unsigned integer0.0020.00655350.3052 A
FormatNormal Signal RangeNormal User RangeResolution
(1)
LOHILOHI
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1794-IF8IHNFXT Data Formats
Data
FormatNormal Signal RangeNormal User RangeResolution
Format
(1)
LOHILOHI
44…20 mA as mA4.0020.04000200001.0 A
54…20 mA as %4.0020.00100001.6 A
64…20 mA Signed 2's Complement 4.0020.00308400.5188 A
74…20 mA as unsigned integer4.0020.00655350.2441 A
(1) All other formats are invalid.
1794-IF8IHNFXT Data Formats Full Reporting Range
Data
Format0.0 mA2.0 mA4.0 mA20.0 mA21.0 mA22.0 mA
Format
00…20 mA as mA020004000200002100022000
10…20 mA as %010002000100001050011000
30…20 mA as unsigned integer065541310765535
44…20 mA as mA
54…20 mA as %
6
4…20 mA Signed 2's Complement
74…20 mA as unsigned integer
(1)
2000
-1250
(2)
(2)
20004000200002100022000
-12500100001062511250
-7710-385503084032767
(2)
0
(2)
0
065535
65535
65535
(2)
65535
32767
(2)
65535
(2)
(2)
(2)
(1) This 4…20 mA format differs from all other 4…20 mA formats in that it continues to report values all the way down to 0 mA while the other 4…20 mA formats stop
reporting @ 2 mA (except for binary, which stops @ 4 mA). In addition, this 4…20 mA format will not force the input value to the Minimum Scale value on an open circuit
or short circuit condition.
(2) These values are under or over the supported user range and are clamped at the lowest/highest supported values.
501014…20 mA in % Full Scale4.00 20.00 010000 (100.00%)1.6 µA
601104…20 mA Signed 2’s
Complement
701114…20 mA in UINT4.00 20.00 0655350.2441 µA
(1) Channel Data Formats are represented by Words 2 and 3 in the 1794-IF8IHNFXT Configuration Data Table on page 43.
(1)
4.0020.000308400.5188 µA
Remote Low Low Alarm Limit
This bit parameter exists on both 1794-IF8IH and 1794-IF8IHNFXT
configuration but have different configuration word number assignations in the
Configuration Data Table. See Data Table Reference.
Sets the limit for the Remote Fault Low Low alarm. This affects Data Formats
0…7. Steps apply to the 4…20 mA range.
For example, a value of 3600 will cause a Remote Fault Low Low Alarm below
3.6 mA (3600*1 A=3.6 mA).
Range: 0…22000 (0=disabled, 1*1 A to 22000*1 A)
Default: 0=disabled
Data Table Reference for 1794-IF8IH: Remote Low Low Alarm Limit,
Configuration Words 12, 16, 20, 24, 28, 32, 36 and 40, bits 0…15
Data Table Reference for 1794-IF8IHNFXT: Remote Low Low Alarm Limit,
Configuration Words 11, 23, 35, 47, 59, 71, 83, 95, bits 0…15
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Data Formats and Error Ranges
Low Alarm
Remote Alarm
normal signal range
20 mA
0 mA
High Alarm
22 mA
Loop
Alarm
Remote Alarm
Format 0
Format 1
Format 3
Data Formats
0.00 mA
0.00 %
0
programmable in
1 µA steps
2 µA steps
0.3502 µA steps
20.00 mA
100.00 %
65,535
programmable in
1 µA steps
2 µA steps
0.3502 µA steps
22.00 mA
110.00 %
22 mA
22 mA
Low Alarm
Remote Alarm
normal signal range
20 mA
0 mA
High Alarm
22 mA
Loop
Alarm
Remote Alarm
Format 4
Format 5
Format 7
Data Formats
0.00 mA
-25.00 %
0
programmable in
1 µA steps
1.6 µA steps
0.24 µA steps
20.00 mA
100.00 %
65,535
22.00 mA
112.50 %
22 mA
22 mA
4.00 mA
0.00 %
0
20 mA
programmable in
1 µA steps
1.6 µA steps
0.24 µA steps
4 mA
Low Alarm
Remote Alarm
normal signal range
20 mA
0 mA
High Alarm
21 mA
Loop
Alarm
Remote Alarm
Format 6
Data Formats
0.00 mA
-25.00 %
0
programmable in
0.5188 µA steps
20.00 mA
100.00 %
65,535
21 mA
4.00 mA
0.00 %
0
20 mA
programmable in
0.5188 µA steps
4 mA
3.2 mA
-5.00 %
3.2 mA
2 mA
-12.50 %
2 mA
20.8 mA
100.50 %
20.8 mA
22 mA
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FLEX I/O Isolated Input/Output HART Analog Modules User Manual
Remote High High Alarm Limit
This bit parameter exists on both 1794-IF8IH and 1794-IF8IHNFXT
configurations but have different configuration word number assignations in the
Configuration Data Table. See Data Table Reference below.
This parameter sets the limit for the Remote Fault High High Alarm. This
affects Data Formats 0…7. Steps apply to the 4…20 mA range and 0…20 mA
range.
For example, a value of 20400 will cause a Remote Fault High High Alarm above
20.4 mA (20400*1 A = 20.4 mA).
Range: 0…22000 (0=disabled, 1*1 A to 22000*1 A)
Default: 0=disabled
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Data Table Reference for 1794-IF8IH: Remote High High Alarm Limit,
Configuration Words 11, 15, 19, 23, 27, 31, 35 and 39, bits 0…15
Data Table Reference for 1794-IF8IHNFXT: Remote High High Alarm Limit,
Configuration Words 10, 22, 34, 46, 58, 70, 82, and 94, bits 0…15
Low Alarm Limit
This bit parameter exists on both 1794-IF8IH and 1794-IF8IHNFXT
configurations but have different configuration word number assignations in the
Configuration Data Tables. See Data Table Reference below.
This parameter sets the limit for the Low Alarm. This affects Data Formats 0…7.
Steps apply to the 4…20 mA range.
For example, a value of 4000 will cause a Low Alarm below 4.0 mA
(4000*1 A = 4 mA).
Range: 0…22000 (0=disabled, 1*1 A to 22000*1 A)
Default: 0=disabled
Data Table Reference for 1794-IF8IH: Low Alarm Limit, Configuration Words
10, 14, 18, 22, 26, 30, 34 and 38, bits 0…15
Data Table Reference for 1794-IF8IHNFXT: Low Alarm Limit, Configuration
Words 9, 21, 33, 45, 57, 69, 81, 93, bits 0…15
High Alarm Limit
This bit parameter exists on both 1794-IF8IH and 1794-IF8IHNFXT
configurations but have different configuration word number assignations in the
Configuration Data Tables. See Data Table Reference.
This parameter sets the limit for the High Alarm. This affects Data Formats 0…7.
Steps apply to the 4…20 mA range and 0…20 mA range.
For example, a value of 20000 will cause a High Alarm above 20.0 mA (20000*1
A = 20 mA).
Range: 0…22000 (0=disabled, 1*1 A to 22000*1 A)
Default: 0=disabled
Data Table Reference for 1794-IF8IH: High Alarm Limit, Configuration Words
9, 13, 17, 21, 25, 29, 33 and 37, bits 0…15
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Data Table Reference for 1794-IF8IHNFXT: High Alarm Limit, Configuration
Words 8, 20, 32, 44, 56, 68, 80, 97, bits 0…15
HART Disable Channel 0…7 (Configuration Word 1 – bits 8…15)
When this bit is set, the I/O module inhibits HART Communication.
Range: 0= enable, 1= disable
Default: 0
HART Current Fault Limit (Configuration Words 4…7 – bits 3…7,
11…15)
This bit parameter applies to 1794-IF8IHNFXT only.
Delivers the percentage value (in steps of 1%, starting @ 5%) of the threshold for
causing a HART current fault indication (input signal deviation HART/
Analog) = 31% maximum deviation.
If there is no HART transmitter on the loop or the loop is not in the transmitter
list the function is switched off internally in the I/O module.
Range: 0=disabled, 1…4= not supported by the I/O module. A configuration
request of 1…4 will cause a value of 5 to be utilized by the module.
5…31= percentage threshold data (5…31%).
Default: 0
HART Data Publishing Disable
This bit parameter exists on both 1794-IF8IH and 1794-IF8IHNFXT
configurations but have different word number assignations in the Configuration
Data Table. See Data Table Reference below.
This bit disables the I/O channel from forwarding the associated HART
Command 3 information from the HART Field device through Cyclic EDT to
the adapter.
This does not disable the module from gathering HART Command 3
information from the HART Field device. As such, HART Command 3
information from the HART Field device is still available via an unconnected
message to the module.
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When the adapter powers up, it reads each module to determine which modules
are present in the Flexbus. For EDT modules, it reads Assembly 125 to gain
knowledge of all assemblies the module has, whether they are EDT/CEDT and
whether they are GET/SET. If an assembly is a CEDT assembly, the adapter
automatically creates a CEDT entry and drops it into the EDT machine to
gather/send this assembly and store the assembly locally in the adapter.
Sometime later, a ForwardOpen configuration arrives by the network for the
module. The adapter proxy strips off a portion (Configuration Part 1) and sends
the rest (Configuration Part 2) on through EDT to the module. Within this
module configuration part are the CMD3 Disable Chx bits. These bits instruct
the module to include or not include CMD3 scanning in the work for the
channel. Users may not have HART devices on every channel so some channels
may want CMD3 disabled. If scanning is disabled, the module also disables the
adapter from including that particular associated assembly in the CEDT
scanning routine by the method described below.
The module uses the CMD3 Disable Chx bits to adjust the CEDT entries in
Assembly 125. Initially, the Assembly 125 CEDT assemblies (46...53) are
identified as CEDT (0xC0 Cyclic EDT Get or 0x40 Cyclic EDT Set). This
causes the adapter to add them to the CEDT scan. If the module receives a
configuration with CMD3 Disable CHx bits set to “1” (disable), the module
changes the appropriate channel Assembly 125 entry from 0xC0 Cyclic EDT Get
to 0x80 EDT Get or 0x40 Cyclic EDT Set to 0x00 EDT Set.
Whenever the adapter receives a ForwardOpen to an EDT module, the adapter
automatically rereads the module’s Assembly 125 to gain a new view of the
assemblies. This reread is to check for any changes of CEDT Assembly status to
EDT status. If a CMD3 Disable Chx was received on any particular channel, now
the previous CEDT assembly is marked as an EDT assembly and the adapter will
not add that assembly to its CEDT scan. This ForwardOpen reread will happen
any time that a module receives a ForwardOpen, including a Null-ForwardOpen
received during system runtime.
Range: 0 = enabled, 1 = disabled
Default: 0
Data Table Reference for 1794-IF8IH: HART Data Publishing Disable (Cn)
Configuration Word 41 – bits 0…7
Data Table Reference for 1794-IF8IHNFXT: HART Data Publishing Disable
(Cn) Configuration Word 104 – bits 0…7
Enable HART PV Upper and Lower Range (Configuration Word
105, bits 8...15)
This configuration bit applies only to the 1794-IF8IHNFXT module only.
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This bit enables the PV Upper and Lower Range (HART Command 35) values.
See Auto-configure HART Device with user-supplied PV Damping and Range
Va l u e s on page 104 for more information.
Range: 0 = true, 1 = false
Default: 0
Enable HART PV Damping Value (Configuration Word 105,
bits 0…7)
This configuration bit applies to the 1794-IF8IHNFXT module only.
When this bit is set, it automatically configures a HART device with usersupplied PV (Primary Value) Damping by sending HART Command 34 to the
device at the time of device connection.
See Auto-configure HART Device with user-supplied PV Damping and Range
Va l u e s on page 104 for more information.
Range: 0 = true, 1 = false
Default: 0
Primary Input Data (RTD
Input Data) for 1794-IF8IH
and 1794-IF8IHNFXT
Primary Input Data for 1794-IF8IH
WordBit
1514131211109876543210
0Channel 0 Input Data
1Channel 1 Input Data
2Channel 2 Input Data
3Channel 3 Input Data
4Channel 4 Input Data
5Channel 5 Input Data
6Channel 6 Input Data
7Channel 7 Input Data
8H7H6 H5H4H3H2H1H0L7 L6 L5 L4 L3 L2 L1 L0
9R7R6 R5R4R3R2R1R0P7 P6P5 P4 P3P2P1 P0
10ReservedDiagnostic Status
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Primary Input Data for 1794-IF8IH
WordBit
1514131211109876543210
11C7C6C5C4C3C2C1C0F7F6F5F4F3F2F1F0
12X7X6X5X4X3X2X1X0Reserved
Where:Hn: Channel n High Alarm
Ln: Channel n Low Alarm
Rn: Channel n Out of Range Alarm
Pn: Channel n Second (Remote) Alarm
Pn: Channel n HART Failure
Cn: Channel n HART Current Fault
Xn: Channel n HART Transmitter Present
Primary Input Data for 1794-IF8IHNFXT
WordBit
1514131211109876543210
0Channel 0 Input Data
1Channel 1 Input Data
2Channel 2 Input Data
3Channel 3 Input Data
4Channel 4 Input Data
5Channel 5 Input Data
6Channel 6 Input Data
7Channel 7 Input Data
8H7H6 H5H4H3H2H1H0L7 L6 L5 L4 L3 L2 L1 L0
9R7R6 R5R4R3R2R1R0P7 P6P5 P4 P3P2P1 P0
10X7X6X5X4X3X2X1X0Diagnostic Status
11C7C6C5C4C3C2C1C0F7F6F5F4F3F2F1F0
Where:Hn: Channel n High Alarm
Ln: Channel n Low Alarm
Rn: Channel n Out of Range Alarm
Pn: Channel n Second (Remote) Alarm
Fn: Channel n HART Failure
Cn: Channel n HART Current Fault
Xn: Channel n HART Transmitter Present
Primary Input Data (Input Words 0…7 – bits 0…15)
Specifies the value of the input data from the module. Specific format is
controlled by module Data Format Control parameter.
Range: See Data Format (8 of 4 bits) on page 49
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Module Diagnostic Status (Input Word 10 – bits 0…7)
Response from module on its condition.
Diagnostic Status for 1794-IF8IH and 1794-IF8IHNFXT
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Diagnostic Status for 1794-IF8IH and 1794-IF8IHNFXT
Diagnostic Status Value: 0ChannelFailure
0x47Channel 7Format Configuration Error
0x50Channel 0ADC Filter Configuration Error
0x51Channel 1ADC Filter Configuration Error
0x52Channel 2ADC Filter Configuration Error
0x53Channel 3ADC Filter Configuration Error
0x54Channel 4ADC Filter Configuration Error
0x55Channel 5ADC Filter Configuration Error
0x56Channel 6ADC Filter Configuration Error
0x57Channel 7ADC Filter Configuration Error
0x70
0x71
0x72
0x73
0x74
0x75
0x76
0x77
(1)
Channel 0PV Configuration Enable selected with
HART Disabled
(1)
Channel 1PV Configuration Enable selected with
HART Disabled
(1)
Channel 2PV Configuration Enable selected with
HART Disabled
(1)
Channel 3PV Configuration Enable selected with
HART Disabled
(1)
Channel 4PV Configuration Enable selected with
HART Disabled
(1)
Channel 5PV Configuration Enable selected with
HART Disabled
(1)
Channel 6PV Configuration Enable selected with
HART Disabled
(1)
Channel 7PV Configuration Enable selected with
HART Disabled
0x80ModuleHardware Failure
0x90Channel 0Calibration Error
0x91Channel 1Calibration Error
0x92Channel 2Calibration Error
0x93Channel 3Calibration Error
0x94Channel 4Calibration Error
0x95Channel 5Calibration Error
0x96Channel 6Calibration Error
0x97Channel 7Calibration Error
0xA0Channel 0Internal Bus Com Error
0xA1Channel 1Internal Bus Com Error
0xA2Channel 2Internal Bus Com Error
0xA3Channel 3Internal Bus Com Error
0xA4Channel 4Internal Bus Com Error
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Diagnostic Status for 1794-IF8IH and 1794-IF8IHNFXT
Diagnostic Status Value: 0ChannelFailure
0xA5Channel 5Internal Bus Com Error
0xA6Channel 6Internal Bus Com Error
0xA7Channel 7Internal Bus Com Error
0xB0
0xB1
0xB2
0xB3
0xB4
0xB5
0xB6
0xB7
(2)
(2)
(2)
(2)
(2)
(2)
(2)
(2)
Channel 0Value set to nearest supported value.
Channel 1Value set to nearest supported value.
Channel 2Value set to nearest supported value.
Channel 3Value set to nearest supported value.
Channel 4Value set to nearest supported value.
Channel 5Value set to nearest supported value.
Channel 6Value set to nearest supported value.
Channel 7Value set to nearest supported value.
OxC0Channel 0Device is write-protected
OxC1Channel 1Device is write-protected
OxC2Channel 2Device is write-protected
OxC3Channel 3Device is write-protected
OxC4Channel 4Device is write-protected
OxC5Channel 5Device is write-protected
OxC6Channel 6Device is write-protected
OxC7Channel 7Device is write-protected
0xD0Channel 0Value out of limits or invalid selection
0xD1Channel 1Value out of limits or invalid selection
0xD2Channel 2Value out of limits or invalid selection
0xD3Channel 3Value out of limits or invalid selection
0xD4Channel 4Value out of limits or invalid selection
0xD5Channel 5Value out of limits or invalid selection
0xD6Channel 6Value out of limits or invalid selection
0xD7Channel 7Value out of limits or invalid selection
0xE0Channel 0Primary value configuration HART
commands not supported
0xE1Channel 1Primary value configuration HART
commands not supported
0xE2Channel 2Primary value configuration HART
commands not supported
0xE3Channel 3Primary value configuration HART
commands not supported
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Diagnostic Status for 1794-IF8IH and 1794-IF8IHNFXT
Diagnostic Status Value: 0ChannelFailure
0xE4Channel 4Primary value configuration HART
0xE5Channel 5Primary value configuration HART
0xE6Channel 6Primary value configuration HART
0xE7Channel 7Primary value configuration HART
0xF0Channel 0Primary value configuration general error
0xF1Channel 1Primary value configuration general error
0xF2Channel 2Primary value configuration general error
0xF3Channel 3Primary value configuration general error
0xF4Channel 4Primary value configuration general error
0xF5Channel 5Primary value configuration general error
0xF6Channel 6Primary value configuration general error
0xF7Channel 7Primary value configuration general error
commands not supported
commands not supported
commands not supported
commands not supported
(1) This does not apply to the output control bits HART OFF that means HART can still be disabled which would
prevent the PV Configuration feature from working until the control bit is cleared.
(2) Applies to 1794-IF8IHNFXT only.
HART Failure (Input Word 11 – bits 0…7)
This bit indicates each time a HART communication failure is detected between
the module and the HART field device (HART FD) on the channel. This failure
could be due to some of the following reasons: time out, response checksum,
parity, framing, HART FD missing, HART FD mismatch from device detected
at last rebuild. If there is a failure, the appropriate channel’s bit is set. The bit is
not latched.
The I/O module performs automatic retries and therefore a user should rarely
recognize communication problems at the protocol layer. Therefore, this flag can
be used to qualify the communication quality.
Range: 0 = No HART failures are detected, 1 = HART failure is detected
HART Current Ratio (Input Word 11 – bits 8…15)
Alarm signal for HART Current Fault, indicating that the HART data value is
outside the HART Current Fault limit percentage. Active when limit is exceeded.
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The analog measured current is compared with the digital current value, read out
dynamically via the HART interface. Active when limit is exceeded. SeeHART
Current Fault Limit (Configuration Words 4…7 – bits 3…7, 11…15) on page 55.
Range: 0 = normal, 1 = fault detected.
1794-IF8IH HART Current Ratio
HART Current Ratio LimitDecimal
Disabled000000
Not applicable100001
Not applicable200010
Not applicable300011
Not applicable400100
5%500101
6%600110
7%700111
8%801000
9%901001
10%1001010
…………………
30%3011110
31%3111111
(1)
Value
Bits
1514131211
76543
(1) HART Current Ratio is represented by Words 4…7 (bits 11…17 and 3…7) in the
Data Table on page 41.
1794-IF8IH Configuration
HART Transmitter List (Input Word 10 – bits 8…15)
Indicates that a HART transmitter has been detected on this channel, during the
last rebuild.
Range: 0 = A HART Transmitter was not detected, 1 = A HART Transmitter is
detected.
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Secondary Input Data
The data in the following table is where the HART protocol device data is
published. The data table is not available as a group in the module. It is formed in
(Cyclic EDT Input Data) for
1794-IF8IH and 1794IF8IHNFXT
the communication adapter by the Cyclic EDT mechanism (adapter to module)
where the adapter cyclically requests a set of module attributes and forms this
data table.
Additionally, the adapter appends the first two words to indicate communication
status between adapter and module regarding each of the cyclic EDT transfers.
Two words are provided, for status, as today’s adapters provide for up to 32 items
in the CEDT queue.
For this module the total Secondary Input Data Table (I) Words = 98, as shown
in the HART Input Data table.
Secondary Input Data (Cyclic Input Data) for the 1794-IF8IH and 1794-IF8IHNFXT Modules
WordBit
1514131211109876543210
0/IReservedCh7 Ch6 Ch5 Ch4 Ch3 Ch2 Ch1 Ch0
HART CMD 3 (Communications Status)
1Reserved
2Ch0 HART Field Device StatusCh0 HART Comm Status
3ReservedFVATVASVAPVACh0 HART Loop Status
4Ch0 HART Primary Value (IEEE 754-1985 Single-Precision 32 bit floating point)
5
6Ch0 HART Secondary Value (IEEE 754-1985 Single-Precision 32 bit floating point)
7
8Ch0 HART Tertiary Value (IEEE 754-1985 Single-Precision 32 bit floating point)
9
10Ch0 HART Fourth (Quaternary) Value (IEEE 754-1985 Single-Precision 32 bit floating point)
11
12Ch0 SV Units CodeCh0 PV Units Code
13Ch0 FV Units CodeCh0 TV Units Code
14…25Words 2…13 for Channel 1
26…37Words 2…13 for Channel 2
38…49Words 2…13 for Channel 3
50…61Words 2…13 for Channel 4
62…73Words 2…13 for Channel 5
74…85Words 2…13 for Channel 6
86…97Words 2…13 for Channel 7
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IMPORTANT
HART Command 3 Communication Status (Secondary Input Word
0, bits 0…7)
These bits indicate status of the CEDT data transfer between the adapter and the
modules. In this module, the CEDT attributes transferred are HART command
3 data for the indicated channel number.
Range: 0 = disabled or no CEDT HART Command 3 Communication error
between the adapter and the I/O module, 1= a CEDT HART Command 3
Communication error between the adapter and the I/O module.
HART Field Device Command and Communication Status
(Secondary Input Word 2, bits 0…7)
This bit indicates the status of HART field device communication for the
channel. It is the first status byte of the HART response and the field device
status. For example: parity error, framing error, invalid selection, or too few data
bytes received.
HART Field Device Status (Secondary Input Word 2 – bits 8…15)
This bit is part of the CMD 3 data response of the HART FD. It is the second
status byte of the HART response and the FD status, for example: primary
variable out of limits or analog output saturated.
CMD3 Second status byte response codes
HART Field Device Status
Bit 0Primary variable out of limits
Bit 1Non-primary variable out of limits
Bit 2Analog output saturated
Bit 3Analog output current fixed
Bit 4More status available
Bit 5Cold start
Bit 6Configuration changed
Bit 7Field device malfunction
When a communication error is reported in the CMD 3
first status byte, the value of bits 0...7 is 0.
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Data Table Reference: HART Field Device Status, Secondary Input Word 2,
bits 8…15.
HART Loop Status (Secondary Input Word 3 – bits 0…7)
This bit indicates the status of the HART loop from the I/O modules point of
view. This byte is generated by the I/O module itself and not by the HART field
device.
HART Loop Status
HART Loop Status
Bit 0
Bit 1HCS_CONNECTED. A connection has been established with this device.
(1)
HCS_COMM_ENABLED, HART is enabled on this channel.
Range: 0 = HART not enabled on this channel, 1 = HART enabled on this channel
Range: 0 = no HART connection on this channel, 1 = HART connection on this
channela
Bit 2HCS_RESPONSE_ERROR. A HART message attempt ended in failure.
This is the Primary HART Variable from the field device. Its datatype is REAL
and it is organized according to Byte Order, see Byte Order (Configuration Word
0 – bits 0…1, 8…9).
HART Secondary Variable (Secondary Input Words 6, 7 – bit
0…15)
This is the Secondary HART Variable from the field device. Its datatype is REAL
and it is organized according to Byte Order, see Byte Order (Configuration Word
0 – bits 0…1, 8…9).
HART Third Variable (Secondary Input Words 8, 9 – bits 0…15)
This is the Third HART Variable from the field device. Its datatype is REAL and
it is organized according to Byte Order, see Byte Order (Configuration Word 0 –
bits 0…1, 8…9).
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This is the Fourth HART Variable from the field device. Its datatype is REAL
and it is organized according to Byte Order, see Byte Order (Configuration Word
0 – bits 0…1, 8…9).
HART Primary Variable Units Code (Secondary Input Word 12 –
bits 0…7)
This is the units code for the Primary HART Variable.
HART Secondary Variable Units Code (Secondary Input Word 12 –
bits 8…15)
This is the units code for the Secondary HART Variable.
HART Third Variable Units Code (Secondary Input Word 13 – bits
0…7)
This is the units code for the Third HART Variable.
HART Fourth Variable Units Code (Secondary Input Word – bits
8…15)
This is the units code for the Fourth HART Variable.
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0-15
16-33
-Vin-V
C O M M O N S
+Vin+V
34-51
A
B
C
1032547698111013121514
2928313033322322252427261716
CH-0
19182120
474649485150414043424544353437363938
CH-1CH-2CH-3CH-4CH-5CH-6CH-7
RTD Output Data for
Output data consists of the EDT Write Word and the HART Control Word.
1794-IF8IHNFXT
RTD Output Data Table – 1794-IF8IHNFXT
WordRead /
Write
14 / EDTWriteRealTR/PFltReservedEDT COntrEDT Write Data
15 / O:0WriteRealTReservedHO7 HO6 HO5 HO4 HO3 HO2 HO1 HO
Where:Flt = Fault
R = Reserved
HO = HART Off Dynamic Control bit. This HART OFF control output bit, along with the HART Disable configuration bit,
determines if HART communication is enabled on a channel. The HART Disable configuration bit has priority and disables all
communication on a channel at all times even when the HART OFF output bit is False(0). If the HART Disable configuration bit
is False(0), then the HART OFF output control bit can be used to dynamically turn HART off and back on again at any time.
Module Configuration for
Data
Type
Bit
15141312111009080706050403020100
Output Connections
the 1794-OF8IH
The 1794-OF8IH module uses the 1794-TB3, Revision B terminal base for full
isolation. Connect the I+ output to the terminal contacts indicated and the
corresponding center return (R) contact. Be sure to observe the polarity indicated
for proper operation. Channels are numbered in order, 0…7, from left to right.
0
1794-OF8IH Terminal Base Connections
Connect an external 24V DC power supply to terminals 34 (V+) and 16 (V-)
observing polarities indicated. Terminals 17…33 are internally shorted to
terminal 16. Terminal 51 is internally shorted to terminal 34. Use the DC output
terminals only for low-power modules, following FLEX I/O power connection
guidelines.
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Please follow wiring instruction for FLEX I/O modules, terminal bases, and
racks.Ground the shield drain wire at one end only. The preferred/required
location is at the sensor end. When connecting the shield drain at the module
end, connect it to earth ground using a panel or DIN rail mounting screw.
Configuration Parameters
for 1794-OF8IH
The last row of the following configuration table provides a brief description of
each configuration parameter bit for the 1794-OF8IH module. The next
sections provide more information about each bit.
All configuration parameters are EDT (Extended Data Transfer) WRITE items.
Configuration is located at EDT assembly 37.
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1794-OF8IH Configuration Data Table
WordBit
1514131211109876543210
0FTREW7EW6EW5EW4BOB
1DH7DH6DH5DH4DH3DH2DH1DH0Reserved
2CH 3 FormatCH 2 FormatCH 1 FormatCH 0 Format
3CH 7 FormatCH 6 FormatCH 5 FormatCH 4 Format
4CH1 HART Current Ratio L1AFS1CH0 HART Current Ratio L0AFS0
5CH3 HART Current RatioL3AFS3CH2 HART Current RatioL2AFS2
6CH5 HART Current RatioL5AFS5CH4 HART Current RatioL4AFS4
7CH7 HART Current RatioL7AFS7CH6 HART Current RatioL6AFS6
8DF7DF6DF5DF4DF3DF2DF1DF0DM7DM6DM5DM4DM3DM2DM1DM0
9Channel 0 Analog Fault Value Output Data
10Channel 1 Analog Fault Value Output Data
11Channel 2 Analog Fault Value Output Data
12Channel 3 Analog Fault Value Output Data
13Channel 4 Analog Fault Value Output Data
14Channel 5 Analog Fault Value Output Data
15Channel 6 Analog Fault Value Output Data
16Channel 7 Analog Fault Value Output Data
17ReservedC7C6C5C4C3C2C1C0
Where:BOA = Byte Order Group A
(1) Not supported in analog 0…20 mA formats.
(2) Lead break must be present for 100 ms or more.
(3) Not shown or used in RSLogix 5000 software.
(4) Reserved data may not be shown in certain controller software.
BOB = Byte Order Group B
Byte Order Group A and B values must match each other. See the Byte Order table.
FT = Local Fault Mode
0: Outputs set to safe value on communication faults only; 1: Outputs set to safe value on any fault
EWn = Fault Enable for wire fault detection on channel n.
0: Disable wire off/lead break detection; 1: Enable wire off lead break detection
CHn HART Current Ratio = HART current fault ratio on channel n
Valid values are 0, 5…31 percent of full scale. A value of 0 disables this feature. See 1794-OF8IH HART Current Ratio
AFSn = Analog Fault Selection for Channel n
See Channel Fault Mode Selection
Ln = Channel n Enable Latching of Wire Fault
0: Unlatched; 1: Latched
DFn = Channel n Digital Fault Mode Selection
0: Reset (0 mA); 1: Hold Last State
DMn = Channel n Enable Digital Mode
0: Analog; 1: Digital
CH N = Channel Data Formats
See Channel Data Formats for 1794-OF8IH
on page 75.
on page 78.
(1)
(3)
RREW3EW2EW1EW0BOA
(4)
(2)
on page 76 for more information.
(1)
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IMPORTANT
Configuration Parameter
This section provides a description of each configuration parameter bit indicated
in the table 1794-OF8IH Configuration Data Table
Descriptions for 1794-OF8IH
Byte Order (Configuration Word 0 – bits 0…1, 8…9)
Selects the byte order of module data.
Note: The MSW and EDT words (Words 0, 1 and 15) of the Primary Input Data
Table are not swapped. All other Primary Input Data and Configuration Data are
adjusted according to the following chart:
on page 71.
Byte Order
Group B
Bit 9Bit 8Bit 1Bit 0Description
0000Little Endian Format (default) — all data entries in
1010Word Swap — word swap only values requiring
0101Byte Swap — byte swap all words in data table.
1111Big Endian Format — all data entries in true Big
Byte Order
Group A
true Little Endian format
more than one word, for example, 32-bit float
values.
Endian format.
Byte Order cannot be changed using RSLogix 5000
software. RSLogix 5000 uses the default Byte Swap setting.
The purpose of this parameter is to allow this module to operate properly within
data networks or systems utilizing various byte orders, across all data types (for
example, Boolean data to 32-bit float data).
Upon receiving the configuration assembly the module must inspect Byte Order
to determine how to interpret the configuration assembly.
Two sets of Byte Order bits are provided since the module will not know at
powerup and configuration reception what Endian format the configuration data
it is receiving in. No matter what the format though, these two 2-bit sets always
convey correct information to the module. Both sets must match each other for
the module to accept the configuration and begin processing it for operation. If
the two sets do not match the module reverts to the last valid configuration (in
case of original start-up this is the default configuration), set module Diagnostic
Status to "2" configuration failure, set outputs to fault states and do not start
operation.
Within the CIP-based Rockwell Automation (RA) control system all data is
transported and utilized in Little Endian format. As such the default mode of
operation for these modules is Little Endian.
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Since these modules are HART modules, and HART data is normally provided
in Big Endian format, the module is responsible for converting any HART in Big
Endian format into Little Endian format.
Examples
In each of the following examples, the module operates internally with little
Endian byte order.
Little Endian Byte Order
If Byte Order indicates Little Endian, utilize the configuration assembly directly.
Partial Configuration Assembly as Received
1Param A Ch2Param B Ch2Param A Ch1Param B Ch1
2Param C CH0 (2nd byte)Param C CH0 (low byte)
3Param C CH0 (high byte)Param C CH0 (3rd byte)
Partial Configuration Assembly after BYTE ORDER Inspection and Processing
1Param A Ch2Param B Ch2Param A Ch1Param B Ch1
2Param C CH0 (2nd byte)Param C CH0 (low byte)
3Param C CH0 (high byte)Param C CH0 (3rd byte)
Provide all data to the Primary Data table in Little Endian byte order.
The following two tables are an example of the Primary Input Data, if Byte Order
indicated Little Endian.
Primary Input Data Before BYTE ORDER Processing for Little Endian
1Ch2 Data A (REAL) (2nd byte)Ch2 Data A (REAL) (low byte)
2Ch2 Data A (REAL) (high byte)Ch2 Data A (REAL) (3rd byte)
3Ch2 Data CCh 2 Data B
Primary Input Data After BYTE ORDER Processing for Little Endian
1Ch2 Data A (REAL) (2nd byte)Ch2 Data A (REAL) (low byte)
2Ch2 Data A (REAL) (high byte)Ch2 Data A (REAL) (3rd byte)
3Ch2 Data CCh 2 Data B
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Word Swap BYTE ORDER
If BYTE ORDER indicates Word Swap, utilize the known structure of the
configuration assembly to reorder multi-word data elements to Little Endian byte
order, for example, word swap FLOATS).
Partial Configuration Assembly as Received
1Param A Ch2Param B Ch2Param A Ch1Param B Ch1
2Param C CH0 (high byte)Param C CH0 (3rd byte)
3Param C CH0 (2nd byte)Param C CH0 (low byte)
Partial Configuration Assembly After BYTE ORDER Inspection and Processing
1Param A Ch2Param B Ch2Param A Ch1Param B Ch1
2Param C CH0 (2nd byte)Param C CH0 (low byte)
3Param C CH0 (high byte)Param C CH0 (3rd byte)
Provide all data to the Primary Data table in Word Swap byte order, except the
MSW and EDT words (Words 0, 1 and 15), these remain in Little Endian byte
order.
The following tables are an example of the Primary Input Data, if BYTE
ORDER indicated Word Swap.
Primary Input Data Before BYTE ORDER Processing for Little Endian
1Ch2 Data A (REAL) (2nd byte)Ch2 Data A (REAL) (low byte)
2Ch2 Data A (REAL) (high byte)Ch2 Data A (REAL) (3rd byte)
3Ch2 Data CCh 2 Data B
Primary Input Data After BYTE ORDER Processing for Little Endian
1Ch2 Data A (REAL) (high byte)Ch2 Data A (REAL) (3rd byte)
2Ch2 Data A (REAL) (2nd byte)Ch2 Data A (REAL) (low byte)
3Ch2 Data CCh 2 Data B
Default: 0
Fault Mode (Configuration Word 0 – bit 15)
Selects whether the channel fault detection is enabled or disabled. There is a
100 ms filter for wire off/lead break and short circuit detection.
Range: 0=Disable, 1= Wire off/lead break and short circuit fault detection
enabled.
Default: 0
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Channel Fault Mode Selection
Analog Fault ModeDecimal ValueBits
98
10
Min Scale000
Max Scale100
Hold Last State210
User Specified Data Value311
Disable HART Channel 0…7 (Configuration Word 17 – bits 0…7)
When this bit is set, the I/O module inhibits HART Communication.
Range: 0=Enable, 1=Disable
Default: 0
HART Current Ratio (Configuration Words 4…7 – bits 3…7,
11…15.)
Delivers the percentage value (in steps of 1%, starting @ 5%) of the threshold for
causing a HART current fault indication (input signal deviation HART/
Analog) = 31% maximum deviation.
If there is no HART transmitter on the loop or the loop is not in the transmitter
list the function is switched off internally in the I/O module.
Range:
0=Disabled,
1…4=Not supported by the I/O module. A configuration request of 1…4 causes a
value of 5 to be utilized by the module.
5…31=Percentage threshold data (5…31%)
Default: 0
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1794-OF8IH HART Current Ratio
HART Current
Ratio Limit
Disabled000000
Not applicable100001
Not applicable200010
Not applicable300011
Not applicable400100
5%500101
6%600110
7%700111
8%801000
9%901001
10%1001010
…………………
30%3011110
31%3111111
Decimal
Value
(1)
Bits
1514131211
76543
(1) HART Current Ratio parameter bits are represented by Configuration Words 4, 5, 6, and 7,
bits 3…7, 11…15. See 1794-OF8IH Configuration Data Table
on page 71.
Data Format (Configuration Words 2, 3 – bits 0…3, 4…7, 8…10,
12…15)
Specifies the module data format for a channel.
If a module channel has never been configured, then it can be assumed to have
the default configuration Analog Data Format "0", 0…20mA and Analog Mode
Fault State minimum range. If a non-assigned format is selected, then the
diagnostic "2" for configuration failure is set and the module channel goes to the
default fault state minimum range.
If the configuration is changed from the default, and then changed again to a
non-assigned format, then the diagnostic bit "2" for configuration failure is set
and the module goes to the fault state for the last valid configuration.
Formats 13 and 14 are 2's complement data formats, and require data to the
module in that form.
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1794-OF8IH Data Formats
Output =
datatable
(
1000
)
Output = 20
datatable
(
10000
)
Output = 20
datatable
(
65535
)
Output =
datatable
(
1000
)
Output = 16
datatable
(
65535
)
+ 4
Output = 16
datatable
(
10000
)
+ 4
FLEX I/O Isolated Input/Output HART Analog Modules User Manual
Range: 0…15. See the 1794-OF8IH Data Formats table.
Data
Format
0 (default) mA as
1% as
20…20 mA—0…22 mA Not Assigned
3Unsigned
4mA as
54…20 mA—4…20 mA Not assigned
64…20 mA4…20 mA Not assigned
7Unsigned
80…20 mA0…20 mA Not assigned
90…20 mA0…20 mA Not assigned
100…20 mA0…20 mA Not assigned
110…20 mA0…20 mA Not assigned
124…20 mANot assigned
134…20 mANot assigned
14% as
154…20 mA4…20 mA Not assigned
FormatResolution Full
Output
Range
0…20 mA
0…20 mA
integer as
0…20 mA
4…20 mA
integer as
4…20 mA
4…20 mA
0.1% of
0…20 mA
0.2% of
0…20 mA
0.03% of
0…20 mA
0.1% of
4…20 mA
0.03% of
4…20 mA
0.16% of
4…20 mA
0…22 mA0…22000
0…22 mA0…11000
0…20 mA0…65535
2…22 mA2000…22000
4…20 mA0…65535
2…22 mA-1250 … +11250
Module Data ProcessingData Table Value
(Interpretation)
(0…22.000 mA)
(0…110.00%)
(0…20 mA)
(2.000…22.000 mA)
(4…20 mA)
(2’s complement)
(-12.50% …
+112.50%)
Count per
mA/
Resolution
1000/
1.0 µA
500/
2.0 µA
3276/
0.305 µA
1000/
1.0 µA
4095/
0.244 µA
625/
1.6 µA
Analog
Fault State
Min=0 mA
Max=22 mA
hold
Last=hold
FS value
Min=0 mA
Max=22 mA
hold
Last=hold
FS value
Min=0 mA
Max=20 mA
hold
Last=hold
FS value
Min=2 mA
Max=22 mA
hold
Last=hold
FS value
Min=4 mA
Max=20 mA
hold
Last=hold
FS value
Min=2 mA
Max=22 mA
hold
Last=hold
FS value
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Channel Data Formats for 1794-OF8IH
(2)
Format
BitsFormat NameSignal
15 141312
(1)
User RangeResolution
Range
11 1098
7654LOHI LOHI
3210
000000…20 mA in Milliamps0.0022.000 (0.000 mA)22000 (22.000 mA)1.0 µA
100010…20 mA in % Full Scale0.0022.000 (0%)11000 (110.00%)2.0 µA
300110…20 mA in UINT0.0020.000655350.3052 µA
(3)
4
(2)
7
(2)
14
(1) Data Format configuration bits are represented by Configuration Words 2 and 3, bits 0…3, 4…7, 8…11, and 12…15. See 1794-OF8IH Configuration Data Table on
page 71.
(2) All other formats are invalid.
(3) HART Communication supported with these data formats only.
01004…20 mA in Milliamps2.0022.002000 (2.000 mA)22000 (22.000 mA)1.0 µA
01114…20 mA in UINT4.0020.000655350.2441 µA
11104…20 mA in % Full Scale2.0022.00-1250 (-12.50%)11250 (112.50%)1.6 µA
If data is sent to the module, which is out of range, the value is clipped and
Diagnostic Data is set to “11” data out of range. To view a graphical
representation of this performance, see the example on page 23
.
Latch Mode (Configuration Words 4…7 – bits 2, 10)
Latch Mode determines channel operation under wire off/lead break fault
conditions. Channel fault detection occurs on a continuous basis. If a fault is
detected, the channel fault alarm is set (if Fault Mode is enabled).
If latch is ON the fault is latched until a Global Reset is issued at which time the
fault is reset.
If latch is OFF the channel reports the fault until the fault is corrected. Upon
correction the fault is reset.
Range: 0=OFF, 1=ON
Default: 0
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Reset
Hold Last
MIN Range
MAX Range
Hold Last
Fault State Value
Normal State
Value
Fault State
Value
Fault
Latch
Mode
100 ms
Filter
Blink
Timer
Reset
Output Mode
(Analog/Digital)
45287
FAULT_ALARM_0
FAULT_LED_0
CHANNEL_0
GLOBAL_RESET
LATCH_MODE_0
FAULT_MODE_0
SHRT_CRKT_0
LB_0
LOCAL_FAULT_MODE_0
PROG/RUN (EDT word Bit 15)
FAULT (EDT word Bit 14)
BUS_COM_FAULT, other internal module faults
ANALOG_DIGITAL_MODE_0
ANALOG_FAULT_STATE_0
DIGITAL_FAULT_STATE_0
OUT_0
ANALOG_FAULT_STATE_VALUE_0
Analog/Digital Output Normal and Fault State Operation
Analog/Digital Output Mode (Configuration Word 8 – bits 0…7)
Selects if the channel acts as a normal analog output or as a switched digital
output.
Analog Output Mode will follow the Analog Data Format selected.
Digital Output Mode will output 0 mA = OFF, 22 mA = ON if the Fault Mode
is 0 = Disable. Digital Output Mode will output 500 μA = OFF, 22 mA = ON if
the Fault Mode is 1 = Wire off fault detection enable.
Range: 0=Normal analog output, 1=Switched digital output
Default: 0
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Analog Fault Mode Selection (Configuration Words 4…7 –
bits 0…1, 8…9)
Determines how the module reacts to faults when channel is used in analog
normal mode.
Range: 0=Go to minimum value of Full Output Range, 1=Go to maximum
value of Full Output Range, 2=Hold last state, 3=Use channel fault state values
given in Words 10…17.
Default: 0
Analog Fault Value Output Data (Configuration Words 9…16 –
bits 0…15)
This parameter specifies the fault state value of the analog output data for the
channel. Specific format is controlled by Analog Data Format Control parameter,
see Data Format (Configuration Words 2, 3 – bits 0…3, 4…7, 8…10, 12…15)
page 76.
on
This data is used when the channel is in analog output mode.
Examples
If you choose format 2 and set the fault state value to 11000 (accordingly
110.00%), the I/O module provides 22 mA in case of fault state.
If you choose format 7 and set the fault state value to 32000, the I/O module
provides 11.813 mA in case of fault state.
The fault state value is treated in the same way as the normal output value is
treated. So you do not need to recalculate the current when you are used to work
in a special format.
Range: See Data Format (Configuration Words 2, 3 – bits 0…3, 4…7, 8…10,
12…15) on page 76.
Default: 0
Digital Mode Fault State (Configuration Word 8 – bit 8…15)
Determines how the module reacts to faults when channel is used in digital
mode.
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Range: 0=Reset, 1=Hold Last State
Default: 0
HART CMD 3 Disable (Configuration Word 7 – bits 0…7)
This bit disables the I/O channel from forwarding the associated HART
Command 3 information from the HART Field device through Cyclic EDT to
the adapter.
This does not disable the module from gathering HART Command 3
information from the HART Field device. As such, HART Command 3
information from the HART Field device is still available via an unconnected
message to the module.
This feature should be exercised by using a Null ForwardOpen method in the
Logix system. That is, the connection to the module and original configuration
has already been accomplished. If utilized, Command 3 Disable should be
utilized under program control (change bit in module configuration tag then
issue reconfiguration message to module) or, more unusually, a manual operation
by an operator (open module profile, change parameter then apply).
When the adapter powers up, it reads each module to determine who is out there.
For EDT modules, it reads Assembly 125 to gain knowledge of all the assemblies
the module has, whether they are EDT/CEDT and whether they are GET/SET.
If an assembly is a CEDT assembly, the adapter automatically creates a CEDT
entry and drops it into its EDT machine to gather/send this assembly and store
the assembly locally in the adapter.
After this powerup process, a ForwardOpen configuration arrives by the network
for the module. The adapter proxy strips off a portion (Configuration Part 1) and
sends the rest (Configuration Part 2) on through EDT to the module. Within
this module configuration part are the CMD3 Disable Chx bits. These bits
instruct the module to include or not include CMD3 scanning in its work for the
channel. Users may not have HART devices on every channel so some channels
may want CMD3 disabled.
If users do disable scanning, the module also disables the adapter from including
that particular associated assembly in the CEDT scanning routine by the
following method:
The module uses the CMD3 Disable Chx bits to adjust the CEDT entries in
Assembly 125. Initially the Assembly 125 CEDT assemblies (46…53) are
identified as CEDT (0xC0 Cyclic EDT Get or 0x40 Cyclic EDT Set) this causes
the adapter to add them to the CEDT scan. If the module receives a
configuration with CMD3 Disable CHx bits set to "1" (disable), the module
changes the appropriate channel Assembly 125 entry from 0xC0 Cyclic EDT Get
to 0x80 EDT Get or 0x40 Cyclic EDT Set to 0x00 EDT Set.
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Whenever the adapter receives a ForwardOpen to an EDT module, the adapter
automatically rereads the module Assembly 125 to gain a new view of the
assemblies. This reread is to check for any changes of CEDT Assembly status to
EDT status. If a CMD3 Disable Chx is received on any particular channel, now
the previous CEDT assembly is marked as an EDT assembly and the adapter does
not add that assembly to the CEDT scan. This ForwardOpen reread happens any
time that a module receives a ForwardOpen, including a Null-ForwardOpen
received during system runtime.
Range: 0=Enabled, 1=Disabled
Default: 0
Primary Input Data (RTD
Output Data) for the
1794-OF8IH
Primary Input Data (RTD Output Data) for 1794-OF8IH
Word/
SISOC
0/MSWReadRealTBus Fail Bits## Words to ReadModule ID/Type
1/EDTReadRealTPU/
2/S0ReadRealTF7F6F5F4F3F2F1F0Diagnostic status
3/S1ReadRealTReserved
4/S2ReadRealTC7C6C5C4‘C3C2C1C0Reserved
5/S3ReadRealTX7X6X5X4X3X2X1X0Reserved
6/EDTWriteRealTProg/
7/O0ReadRealTReser
8/O1WriteRealTOutput Data Channel 0
9/O2ReadRealTOutput Data Channel 1
10/O3ReadRealTOutput Data Channel 2
11/O4ReadRealTOutput Data Channel 3
12/O5ReadRealTOutput Data Channel 4
13/O6ReadRealTOutput Data Channel 5
14/O7ReadRealTOutput Data Channel 6
15/EDTReadRealTOutput Data Channel 7
Where:Fn: Channel n Fault alarm
Read/
Write
Cn: Channel n HART Current Fault
Xn: HART Transmitter List
Dn: Channel n Digital out
Data
Transport
Bit
1514131211109876543210
Cfg
Run
ved
Event
ReservedReadWriteSeqCountEDT Data Byte from Module
Pdg
FaultReservedReadWriteSeqCountEDT Data Byte from Module
Global
ReservedD7D6D5D4D3D2D1D0
reset
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Fault Alarm (S0 Read Word – bits 8…15)
Alarm signal for open-wire channel fault, detected @ <2 mA (<500 μA in digital
mode) and short circuit (R<42 in the 4…20 mA range, <86 in digital mode,
channel off).
This alarm is disabled when a data format is selected which includes 0 mA.
Range: 0=Normal, 1=Wire off/short circuit fault detected
Default: 0
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Diagnostic Data
Diagnostic Status Value: 0 ChannelFailure
0x56Channel 6Data out of range
0x57Channel 7Data out of range
0x80ModuleHardware Failure
0x90Channel 0Calibration Error
0x91Channel 1Calibration Error
0x92Channel 2Calibration Error
0x93Channel 3Calibration Error
0x94Channel 4Calibration Error
0x95Channel 5Calibration Error
0x96Channel 6Calibration Error
0x97Channel 7Calibration Error
0xA0Channel 0Internal Bus Com Error
0xA1Channel 1Internal Bus Com Error
0xA2Channel 2Internal Bus Com Error
0xA3Channel 3Internal Bus Com Error
0xA4Channel 4Internal Bus Com Error
0xA5Channel 5Internal Bus Com Error
0xA6Channel 6Internal Bus Com Error
0xA7Channel 7Internal Bus Com Error
HART Status Fields
The 1794-OF8IH module supports two connections for pass-through messages.
Pass-through messages provide the ability to send HART messages to the HART
device by passing through the I/O Module. In addition, HART device
information that is automatically gathered by the I/O module may be accessed
through this interface.
The 1794-OF8IH module provides eight queues for each of the two
connections. This allows each connection to have up to eight messages pending
at any given time, one for each channel. HART pass-through message
implements a timeout, which is fixed at 20 seconds.
The first connection is provided for a ladder logic user. The following status bits
are provided to simplify ladder logic. The second connection does not have status
bits provided in the RTD. It can obtain this status by implementing polling
messages using the pass-through message interface.
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HART Current Fault (S2 Read Word – bits 8…15)
Alarm signal for HART Current Fault, indicating the HART data value is
outside the HART Current Fault limit percentage. Active when limit is exceeded.
The analog measured current is compared with the digital current value, read out
dynamically via the HART interface. Active when limit is exceeded. See HART
Current Ratio (Configuration Words 4…7 – bits 3…7, 11…15.) on page 75.
Range: 0=Normal, 1=Fault detected
HART Transmitter List (S3 Read Word – bits 8…15)
Indicates that a HART transmitter has been detected on this channel, during the
last rebuild.
Range: 0=A HART Transmitter was not detected, 1=A HART Transmitter was
detected.
Primary Output Data (RTD
Output Data) for 1794-OF8IH
Analog Output Data
Specifies the value of the analog output data to the module. Specific format is
controlled by Module Data Format Control parameter. This data is used when
the channel is in analog output mode.
Range: See Data Format (Configuration Words 2, 3 – bits 0…3, 4…7, 8…10,
12…15) on page 76.
Digital Output Data (O0 Read Word – bits 0…7)
Specifies the value of the digital output data to the module. This data is used
when the channel is in digital output mode.
Range:
If the Fault Mode is 0=Disable: 0=Output 0 mA = OFF, 1=22 mA = ON.
If the Fault Mode is 1=Wire off fault detection enabled: 0=Output
500 μA=OFF, 1=22 mA=ON.
See Analog/Digital Output Mode (Configuration Word 8 – bits 0…7)
page 79.
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Global Reset (O0 Read Word – bit 14)
This bit resets all latched fault alarms. It acts in conjunction with the Latch Retry
parameter. If any channel faults occur, the Latch Retry parameter can be set to
cause the fault to be latched and the output to go to its fault state value if the
Local Fault mode bit is set.
This is an edge triggered signal. It must first be set to the “1” state, reset will then
occur on the “1” to “0” transition.
Range: 0=Normal, 1=Reset.
Fault (EDT Write Word – bit 14) and Run/Prog (EDT Write Word –
bit 13)
Fault bit = signal from the adapter to the module that communication has been
interrupted with the network.
Prog/Run bit = signal from the adapter to the module of the processor mode.
These 2 bits are used together.
When the adapter and I/O are first powered-up, the Fault bit is set to ‘0’, by the
adapter. On powerup, any module outputs remain OFF (0 mA out) or reset.
When the Fault bit is a ‘1’, the outputs follow the data specified in output data
words if the Prog/Run bit indicates that the processor is in the Run mode ‘1’.
When the Fault bit is a ‘0’ or Prog/Run bit indicates that the processor is in the
Program mode ‘0’, the outputs follow the data specified in fault state
configuration data words. The following is a truth table to explain this in more
detail.
Prog/RunFaultDescription
11Module outputs follow the output data table
all other statesModule outputs follow Fault State Values
Range: 0=Local control of outputs, 1=Adapter controls outputs
Default: 0
Data Table Reference: Fault, EDT write word, bit 14
Run/Prog Range: 0=Processor in PROGRAM mode, 1=Processor in RUN
mode
Default: 0
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Secondary Input Data
The description of this data table section is identical for HART input or output
modules.
(Cyclic EDT Input Data) for
1794-OF8IH
Secondary Input Data (Cyclic EDT Input Data) for 1794-OF8IH
WordBit
1514131211109876543210
0ReservedCH7CH6CH5CH4CH3CH2CH1CH0
1Reserved
2CH0 HART Field Device StatusCH0 HART Comm Status
3FVATVASVAPVACH0 HART Loop Status
4CH0 HART Primary Value (IEEE 754-1985 Single-Precision 32 bit floating point)
5
6CH0 HART Secondary Value (IEEE 754-1985 Single-Precision 32 bit floating point)
7
8CH0 HART Tertiary Value (IEEE 754-1985 Single-Precision 32 bit floating point
9
10CH0 HART Fourth (Quaternary) Value (IEEE 754-1985 Single-Precision 32 bit floating point)
11
12CH0 SV Units CodeCH0 PV Units Code
13CH0 FV Units CodeCH0 TV Units Code
14…25Words 2…13 for channel 1
26…37Words 2…13 for channel 2
38…49Words 2…13 for channel 3
50…61Words 2…13 for channel 4
62…73Words 2…13 for channel 5
74…85Words 2…13 for channel 6
86…97Words 2…13 for channel 7
Bit parameter descriptions are provided in the last row of the following table
(HART CMD 3 Communications Status)
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Secondary Input Data (Cyclic EDT Input Data) for 1794-OF8IH
WordBit
1514131211109876543210
Where:CHn: HART CMD 3 Communication Status
0: HART CMD 3 Communication Disabled or No Error; 1: HART CMD 3 Communication Error between Adapter and Module
CHn: HART Comm Status (HART CMD3 Response first status byte)
See HART Command 3 Communication Status (Input Word 0 – bits 0…7)
CHn: HART Field Device Status (HART CMD3 Response second status byte)
See HART Field Device Status (Secondary Input Word 2 – bits 8…15)
HART Loop Status
Bit 0: HART enable
Bit 1: Device Connected0: Not Connected1: Connected
Bit 2: Response Error0: No HART message failure1: Response ended in error
Bit 3: CMD 48 Update 0: CMD 48 not updated1: CMD 48 updated
Bit 4: HART Loop Tolerance Error0: No HART Current Fault1:HART Current Fault
Bit 5: HART Update0: HART Device information not updated1: HART Device information updated since last read
Bit 6: HART message0: No new message1: HART user message queue has completed a message
Bit 7Reserved
PVA – The primary variable for this channel has been acquired.
SVA – The secondary variable for this channel has been acquired.
TVA – The tertiary variable for this channel has been acquired.
FVA – The fourth (quaternary) variable for this channel has been acquired.
0: Disabled1: Enabled
on page 89.
on page 88.
Secondary Data Table Section Created by the Adapter
The description of this data table section is identical for HART input or output
modules. See HART Command 3 Communication Status (Secondary Input
Word 0, bits 0…7) on page 65 for more information.
HART Command 3 Communication Status (Input Word 0 –
bits 0…7)
The description of this data table section is identical for HART input or output
modules. See HART Command 3 Communication Status (Secondary Input
Word 0, bits 0…7) on page 65 for more information.
Secondary Data Table Section from Module CEDT Attribute
The description of this data table section is identical for HART input or output
modules.
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IMPORTANT
HART Field Device Status (Secondary Input Word 2 – bits 8…15)
This byte is part of the CMD 3 data response of the HART FD. It is the second
status byte of the HART response and the FD status, example: “primary variable
out of limits” or “analog output saturated”.
CMD 3 Second Status byte response codes
HART Field Device Status
Bit 0Primary variable out of limits
Bit 1Non-primary variable out of limits
Bit 2Analog output saturated
Bit 3Analog output current fixed
Bit 4More status available
Bit 5Cold start
Bit 6Configuration changed
Bit 7Field device malfunction
Data Table Reference: HART Field Device Status, Secondary Input Word 2, bits
8…15.
Interpret the Status
The module status indicators conform to the FLEX I/O standard. The module
will have a single Red and Green indicators for global module status/power
Indicators
indication.
The module supports six states, common to all Phase 1 EDT-compliant modules,
as described below. A single bi-color indicator displays the module status as given
below.
Module Status Indicators
Module
State
NewPower up initialization is complete and self-test has
No ConfigModule has not received configuration from Master.
IdleController in Program mode.
ConditionPU BitProg/Run bitFault bitLED Color and
been passed. Loads stored configuration, if it exists.
Read Module Information Block.
It can Set and Get attributes.
Communication is normal.
(1)
When a communication error is reported in the CMD 3 first status byte,
bits 0...7 will have the value of 0.
State
(2)
*
0**Green, blink @ 1 Hz
101Green, blink @ 1 Hz
**Red, blink @ 1 Hz
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IMPORTANT
IMPORTANT
Module Status Indicators
Module
State
ActiveController in Run mode and communication is normal. 111Green, solid
FaultFLEX I/O Communications Fault or PU bit is one
Fatal faultModule fails self test or detects illegal state
OffExternal power has not been applied.Off
(1) The status bits in the table correspond to module status bits available in the module status word.
(2) Bit state flagged as '*' depends on the state transition, per FLEX I/O Systems Specifications.
Edit Your 1794-IF8IHNFXT
ConditionPU BitProg/Run bitFault bitLED Color and
State
**0Green, blink@ 1 Hz
and Fault=0
***Red, solid
transition.
Studio 5000 Logix Designer® (or RSLogix 5000) programming software
automatically creates module-defined data types and tags when a module is
Configuration with Studio
5000 Logix Designer
created. This section describes how to modify the default configuration for your
1794-IF8IHNFXT module.
(Full Profile)
Configuring the 1794-IF8IH and 1794-OF8IH modules require
programming with RSLogix 5000 version 17. Configuration for the
1794-IF8IHNFXT module is done through the Module Definition interface
using Logix Designer version 24 and later, as described in the next
sections. See Use the 1794-IF8IHNFXT with the Generic and Thin Profiles
on page 153 if you are using RSLogix 5000 version 23 or earlier.
Data types symbolically name module configuration, input, and output data.
Tags let you provide each a unique name, such as where the user-defined data type
and slot reside on the controller. This information is used to communicate data
between the controller and module.
After you have set configuration for a module, you can review and change your
choices. You can change configuration data and download it to the controller
while online. This is called dynamic reconfiguration.
Your freedom to change some configurable features, though, depends on whether
the controller is in Remote Run Mode or Program Mode.
Although you can change configuration while online, you must go
offline to add or delete modules from the project.
The editing process begins on the main page of RSLogix 5000 or Logix Designer
software.
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TIP
1. On the I/O Configuration tree for your project in RSLogix 5000,
add your 1794-IF8IHNFXT module.
On the New Module dialog that appears when you add your module to the
I/O Configuration tree, specify the following properties of the module.
2. Click Open Module Properties. The Module Properties dialog appears
and has the following tabs available for configuration.
3. Click any of the tabs to edit the parameters for your module.
The next sections show you how to edit the different tabs in the Module
Properties dialog.
Tabs can be selected in any order. The following examples are for
instructional purposes.
General Tab
The General tab allows you to edit general properties such as Name, Description,
and Slot for your module, which you can specify in the New Module dialog, as
shown previously.
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You also can edit Module Definition properties such as revision and electronic
keying.
General Tab Field Descriptions
Field NameDescription
RevisionSpecifies the module major and minor revision.
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General Tab Field Descriptions
Field NameDescription
Electronic KeyingThe electronic keying feature automatically compares the
expected module, as shown in the RSLogix 5000 I/O Configuration
tree, to the physical module before I/O communication begins.
You can use electronic keying to help prevent communication to a
module that does not match the type and revision expected.
For each module in the I/O Configuration tree, the user-selected
keying option determines if, and how, an electronic keying check
is performed.
Typically, three keying options are available:
² Exact Match
² Compatible Module (default)
² Disable Keying
Exact Match is an electronic keying protection mode that
requires the physical module and the module configured in the
software to match according to vendor, catalog number, major
revision, and minor revision.
Compatible Module indicates that the module determines
whether to accept or reject communication. Compatible Keying is
the default setting. It allows the physical module to accept the key
of the module configured in the software, if the configured module
is one the physical module is capable of emulating. The exact
level of emulation required is product and revision specific.
Disable Keying indicates that the keying attributes are not
considered when attempting to communicate with a module.
Other attributes, such as data size and format, are considered and
must be acceptable before I/O communication is established.
With Disabled Keying, I/O communication may occur with a
module other than the type specified in the I/O configuration tree
with unpredictable results. We generally do not recommend using
Disabled Keying.
Comm FormatThe following Comm Format options are available:
² Input Data – specifies an independent connection where a
device receives inputs from the target device and send
configuration data to the target device. An Input Only
connection does not send outputs; it only receives inputs. You
can specify multiple Input Only connections to the target device
from different originators.
² Listen-Only and Input Data – The Listen Only mode option
lets the controller and module establish communication without
the controller sending any configuration data.
² Input Data and HART PV
² Listen-Only, Input Data and HART PV
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Connection Tab
The Connection tab on the Module Properties dialog box lets you enter a
requested packet interval (RPI), inhibit a module, and set a connection fault
when the controller is in Run mode. The RPI provides a defined, maximum
period of time when data is transferred to the owner-controller.
1. Choose from the options on the Connection tab.
Connection Tab Field Descriptions
FieldDescription
Requested Packet
Interval (RPI) (ms)
Inhibit ModuleCheck the box to prevent communication between the owner-
Major Fault On
Controller If Connection
Fails While in Run Mode
Use Unicast Connection
over EtherNet/IP
Module FaultThe fault box is empty if you are offline. The type of connection
A user-defined rate at which the module updates the
information sent to its owner-controller.
This interval defines the slowest rate at which a module sends
its data to the owner-controller. The time ranges from
2.0…750 ms and is sent to the module with all other
configuration parameters.
controller and the module. This option allows for maintenance
of the module without faults being reported to the controller.
Check the box to create a major fault if there is a connection
failure with the controller while in Run mode.
This option is enabled by default.
Unicast connections are point to point transmissions between
a source node and destination node on the network. A Frame is
sent to a single destination.
fault appears in the text box if a fault occurs when the module
is online.
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2. Do one of the following:
² Click Apply to store a change but stay on the dialog box to choose
another tab.
² Click OK if you are finished making changes.
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Configuration Tab
The Configuration tab on the Module Properties dialog box lets you program
information on each of the eight channels on the 1794-IF8IHNFXT module.
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1. Choose from the options on the Configuration tab.
Configuration tab
FieldDescription
ChannelIndicates the eight input channels 0…7.
Current rangeCurrent range with the following value options:
² 0…20 mA Milliamps (Default)
² 0…20 mA % Full Scale
² 0…20 mA BINARY
² 4…20 mA Milliamps
² 4…20 mA % Full Scale
² 4…20 mA Signed 2's Complement
² 4…20 mA Binary
Digital filterServes to reject higher frequency noise and harmonics.
Choose a value in Hz that specifies the time constant for a
digital first order lowpass filter on the input. A value of 0
disables the filter.
² 242 Hz (Default)
² 123 Hz
² 62 Hz
² 19.6 Hz
² 16.7 Hz
² 10 Hz
² 4.17 Hz
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Configuration tab
FieldDescription
Enable HARTAllows to enable or disable HART feature. Check the box to
enable HART.
Default: Unchecked.
The Enable HART check box (DHn bit in the configuration
data table) along with the HART OFF Dynamic control bit
determines if HART communication is enabled on a
channel.
The Enable HART check box has priority and will disable all
HART communication on a channel at all times even when
the HART OFF Dynamic control bit is False(0). If Enable
HART check box is checked, then the HART OFF output
control bit can be used to dynamically turn HART off and
back on again at any time.
See HART On/Off at Dynamic Runtime
Enable HART Current Ratio Allows for enabling or disabling ratio limit per channel.
Default: Unchecked.
HART Current Ratio LimitSets the ratio limit. For more information about this
parameter, see HART Current Ratio (Configuration Words
4…7 – bits 3…7, 11…15.) on page 75.
on page 98.
2. Do one of the following:
² Click Apply to store a change but stay on the dialog box to choose
another tab.
² Click OK if you are finished making changes.
HART On/Off at Dynamic Runtime
To enable HART at runtime:
1. Ensure that the Enable HART check box in Configuration tab is checked.
2. Change the HART OFF Dynamic Control bit (ChxxHARTCommOff)
to 1 to turn off HART dynamically.
3. Change the HART OFF Dynamic Control bit (ChxxHARTCommOff)
to 0 to turn on HART dynamically again.
Edit the output controller tag ChxxHARTCommOff using a configuration
software such as RSLogix 5000 version 24. To enable HART on each channel, set
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the tag value to 0. To disable HART, set the value
to 1 as shown below.
The HART OFF dynamic control output bit, along with the HART Disable
configuration bit, determines if HART communication is enabled on a Channel.
The HART Disable (DHn) configuration bit has priority and disables all HART
communication on a channel at all times even when the HART OFF output bit is
False(0). If the HART Disable configuration bit is False(0), then the HART
OFF output control bit can be used to turn HART off and on dynamically at any
time.
Alarm Tab
The Alarm tab on the Module Properties dialog box lets you program high and
low limits, and disable and latch alarms per channel.
Rockwell Automation Publication 1794-UM065D-EN-P - April 202099
FLEX I/O Isolated Input/Output HART Analog Modules User Manual
Click Channel button to set limits
and alarm configuration for each
of the 4 channels.
Use the sliders to set limits. HH
slider sets High High limits; HI
sets High limits; LL for Low Low;
and LO for Low.
1. Choose from the options on the Alarm tab.
Alarm Configuration Tab Field Descriptions
FieldWhat to doDescription
ChannelSelect a push
button to
correspond to a
channel (0…7)
Process AlarmsType a value for each of the four alarm trigger
High HighChoose from
-32,768...32,767
HighChoose from
-32,768...32,767
Click the channel that is being configured.
points that alert you when the module has
exceeded these limitations.
You also can use the respective slider icon to
set a trigger value.
Select a value so that any value out of range
in this field causes a profile validation error.
This value also appears in the HH slider on
this dialog.
Select a value so that any value out of range
in this field causes a profile validation error.
This value also appears in the HI slider on this
dialog.
100Rockwell Automation Publication 1794-UM065D-EN-P - April 2020
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