The Allen-Bradley 1771-IXHR, also cataloged as the 1771-IXHR High-Resolution Thermocouple Module, operates as a dedicated hardware component for temperature and millivolt signal digitization within Allen-Bradley 1771 Universal I/O Chassis platforms.
Hardware Specifications
Parameter
Specification
Model
1771-IXHR
Brand
Allen-Bradley
Origin
USA
Weight
1.50 lbs (0.68 kg)
Dimensions
Standard 1771 single-slot chassis module
Operating Temp
0 to 60 deg C (32 to 140 deg F)
Power Consumption
4.255 W maximum (14.5 BTU/hr thermal dissipation)
Backplane Current
750 mA at 5 VDC
Input Channels
8 floating differential inputs
Input Types
Thermocouple (Types B, E, J, K, R, S, T) and +/- 99.99 mV
Resolution
15 bits + sign (0.1 deg C / 0.1 deg F or 1 uV per bit)
Channel Update Speed
25 ms for all 8 channels
Wiring Arm
1771-WH (or 1771-WI)
High-Density I/O Isolation and Deterministic Network Response
The 1771-IXHR module processes low-level thermocouple millivolt signals through on-board cold junction compensation, converting analog temperature metrics into natural binary data blocks for PLC-5 processors. Operating within EtherNet/IP and remote I/O deterministic network architectures, the internal analog front-end isolates common-mode noise and floating sensor offsets, ensuring stable backplane bus communication velocity without delaying scan times across adjacent control cards.
Frequently Asked Questions
Q: Does the 1771-IXHR require an external power supply for signal processing?
A: No external field power is required; the 1771-IXHR derives all operating power directly from the 1771 chassis backplane bus, drawing 750 mA at 5 VDC.
Q: What keying pin positions are required on the chassis backplane slot for the 1771-IXHR module?
A: Keying bands must be positioned between pins 20 and 22 on the upper backplane connector and between pins 24 and 26 on the lower connector.
Field Installation Guidelines
De-energize 1771 chassis backplane power before inserting or removing the 1771-IXHR module from the rack slot.
Verify that cold junction compensation sensors are correctly wired to the designated terminal locations on the field wiring arm.
Use shielded twisted-pair extension wire matched specifically to the thermocouple type, grounding the shield wire at a single point to prevent ground loop noise.
Route low-millivolt thermocouple wiring away from high-voltage AC motor lines, switching power supplies, and output relays.
