Product Overview
The Allen-Bradley 1746-NR8 is an RTD/Resistance Analog Input Module designed for the SLC 500 system. This module features eight channels compatible with RTD sensors such as Platinum (385), Platinum (3916), Copper (426), Nickel (618), Nickel (672), and Nickel Iron (518). It also accepts direct resistance inputs across ranges including 0-150 ohms, 0-500 ohms, 0-1000 ohms, and 0-300 ohms. The Allen-Bradley 1746-NR8 supports both fixed and modular SLC 500 chassis configurations, making it a versatile choice for temperature and resistance measurement applications.
Technical Specifications
| Parameter |
Value |
| Inputs |
8 |
| Backplane Current (5V) |
100 mA |
| Backplane Current (24V) |
55 mA |
| Update Time |
6 ms to 2 seconds |
| Operating Temperature |
0 to 60 °C |
| Storage Temperature |
-40 to 85 °C |
| Resolution |
0.01 °C |
| Power Consumption |
1.82 W max (0.5 W @ 5 Vdc, 1.32 W @ 24 Vdc) |
| Step Response |
60 ms in, 2.5 ms out |
| A/D Conversion |
Sigma-delta modulation |
These specifications are sourced directly from the product data. The Allen-Bradley 1746-NR8 delivers reliable performance in demanding industrial environments.
Industry Applications
The Allen-Bradley 1746-NR8 module is ideal for temperature monitoring in manufacturing processes, such as plastic extrusion or chemical reactors. Its resistance measurement capability allows for precise tracking of mechanical displacement, making it useful for position feedback in linear actuators. In process control, the 1746-NR8 ensures accurate data acquisition, reducing downtime and improving product quality.
Installation & Setup
Install the Allen-Bradley 1746-NR8 in any I/O chassis slot except slot 0. The module is powered via the backplane; no external supply is needed. For 2-wire RTD sensors, use Belden 9501 shielded cable or equivalent, and minimize cable length to maintain accuracy. For 3-wire or 4-wire RTDs, Belden 9533 or Belden 83503 cable is recommended. Use the compatible 1746-RT-35 terminal block for wiring. The module supports auto-calibration at power-up or every 5 minutes as programmed.
Compatibility & Integration
The Allen-Bradley 1746-NR8 is fully compatible with Allen-Bradley SLC 500 fixed and modular controllers. It occupies one slot and integrates seamlessly into existing control systems. The module works with 2-wire, 3-wire, and 4-wire RTD sensors, providing flexibility for various installation scenarios.
Selection Guide
Before purchasing the Allen-Bradley 1746-NR8, verify your system's backplane power capacity and available slot. Confirm the RTD types required for your application. For a reliable supply, consider ordering from UBEST Automation. This module is a cost-effective choice for upgrading older RTD input solutions, offering improved accuracy and lower maintenance.