The Allen-Bradley 1794-IR8 FLEX I/O RTD Input Module is a robust, high-reliability solution designed for direct temperature measurement in harsh industrial environments. As part of the Rockwell Automation FLEX I/O family, this module offers eight individually isolated RTD input channels, each configurable for 2-wire, 3-wire, or 4-wire RTD sensors to eliminate lead resistance errors. The 1794-IR8 supports a wide range of RTD types including platinum (Pt100, Pt1000), nickel (Ni120, Ni1000), and copper (Cu10), with a measurement range from -200°C to +850°C (depending on sensor) and a resolution of 0.1°C. Its 16-bit A/D converter ensures high accuracy, while the module's built-in cold junction compensation (CJC) and per-channel open/short detection guarantee reliable data integrity. Designed for demanding applications such as oil & gas, chemical processing, and power generation, the 1794-IR8 operates over a 0-60°C ambient temperature range and features a rugged IP20-rated enclosure. It communicates via the FLEX I/O backplane, offering seamless integration with Allen-Bradley controllers and supporting remote I/O configurations up to 1,500 meters.
| Parameter |
Specification |
| Module Type |
RTD Input Module |
| Number of Channels |
8 (individually isolated) |
| Input Type |
RTD (Resistance Temperature Detector) |
| Supported RTD Types |
Pt100, Pt1000, Ni120, Ni1000, Cu10 (per IEC 751, DIN 43760, JIS C1604) |
| Wiring Configurations |
2-wire, 3-wire, 4-wire (per channel selectable) |
| Measurement Range |
-200°C to +850°C (Pt100); -200°C to +600°C (Pt1000); -60°C to +250°C (Ni120) |
| Resolution |
0.1°C (16-bit A/D converter) |
| Accuracy |
±0.1% of reading ±0.5°C (Pt100 at 25°C, 3-wire) |
| Input Impedance |
> 10 MΩ |
| Update Rate |
55 ms per channel (typical) |
| Isolation Voltage |
250V AC continuous between channels and backplane |
| Cold Junction Compensation |
Built-in, per module |
| Diagnostics |
Per-channel open/short detection, under-range/over-range indication |
| Power Supply |
5V DC from FLEX I/O backplane (typical 150 mA) |
| Backplane Current |
150 mA Standard Models 5V DC (max) |
| Operating Temperature |
0°C to +60°C (32°F to 140°F) |
| Storage Temperature |
-40°C to +85°C (-40°F to 185°F) |
| Relative Humidity |
5% to 95% non-condensing |
| Enclosure Rating |
IP20 |
| Dimensions (H x W x D) |
94 x 51 x 75 mm (3.7 x 2.0 x 3.0 in) |
| Weight |
Approx. 200 g (7.0 oz) |
| Communication Protocol |
FLEX I/O backplane (proprietary Allen-Bradley) |
| Compatible Controllers |
ControlLogix, CompactLogix, SLC 500, PLC-5 (via FLEX I/O adapter) |
| Maximum Cable Length (RTD) |
100 m (328 ft) for 3-wire, 200 m (656 ft) for 4-wire |
| Certifications |
CE, UL, cUL, ATEX (for hazardous locations), IECEx |
| Mounting |
DIN rail (EN 50022) or panel mount |
What Does Our Clients Say
Mitsubishi MR-J4
Laura Navas
Great product!
2019/12/01
Keyence sensor
EQDR SALES
Original and fast!
2020/02/22