Specifications

Publication 1794-SG002D-EN-P - May 2012
Select FLEX Ex I/O Modules 95
HART Interface Modules
FLEX Ex HART analog modules (1797-IE8H and 1797-OE8H) are ideal for
use in applications that need connection with FDT (Field Device Tool)
compatible asset management software, such as Rockwell Software FieldCare
HART Communication bundle or Endress + Hauser Fieldcare. For HART
Device Type Management (DTM) programs and drivers, go to
http://www.ab.com/io
, and select Configurations Files, DTM files for HART.
• FLEX HART analog modules can be used on ControlNet or EtherNet/IP.
The FLEX Ex Ethernet adapter requires firmware v3.1 or later, which is
flash upgradeable, to support these modules.
• Each HART field device is wired to its own input or output channel:
– 8 single-ended channels
– does not support multi-drop
– 2- or 3-wire devices
• HART commands can be transmitted by unscheduled message:
– sample RLL subroutines are available.
– currently limited to one instance of RLL subroutine per module, one
channel at a time.
Input signal range 0…500 Ω
-40…100 mV
TC
RTD
Settling time 8 ms to 99% of final value (mV mode, °F thermocouple)
Open RTD detection Out of range upscale reading
Lead resistance compensation < 15 Ω total
Transfer characteristics, accuracy RTD: 0.1% of span @ 20 °C, filter cutoff < 1 Hz
Thermocouple: 0.1% of span @ 20 °C, filter cutoff < 1 Hz
Cold junction compensation: ± 1 °C
Temperature drift 150ppm/ °C (primary range)
Data organization Overrange Alarm – Individually for each channel
Lead Breakage Alarm – Individually for each channel
Fault State – Individually for each channel (includes overrange,
lead breakage and short circuit)
Sensor Mode RTD 2, 3, or 4-wire – Common to groups of 4
channels (ch 0…3, ch 4…7)
TC Sensor Type (for example TC, Type B, E, J..., RTD or mV) -
Common to groups of 4 channels (ch 0…3, ch 4…7)
Internal Reference Junction (TC mode) – Common to all
channels (0 °C, 20 °C, 25 °C, 30 °C, 40 °C, 50 °C, 60 °C, 70 °C
Noxious gas exposure Tested to severity level G3, ISA-S71.04-1985
FLEX Ex power consumption 1.6 W @ 9V
Power dissipation, max 1.6 W
Thermal dissipation, max 5.46 BTU/hr
Dimensions (H x W x D) 46 x 94 x 75 mm (1.8 x 3.7 x 2.95 in.)
94 x 94 x 91 mm (3.7 x 3.7 x 3.6 in.) installed
8 Point 16-bit Non-isolated RTD Thermocouple/mV Input Module
Specification 1797-IRT8