Product Description
Allen-Bradley 1746-NR4 SLC 500 RTD/Resistance Input Module
Product Overview
The Allen-Bradley 1746-NR4 is an RTD/Resistance Input Module for the SLC 500 system, designed to interface with resistance temperature detectors (RTDs) and resistance-based devices. It offers high accuracy, configurable filtering, and isolation for industrial temperature monitoring applications.
Technical Specifications
| Attribute | 1746-NR4 Details |
|---|---|
| Manufacturer | Allen-Bradley |
| Model Number | 1746-NR4 |
| Description | SLC 500 RTD/Resistance Input Module |
| Backplane Current Consumption | 50 mA at 5V DC, 50 mA at 24V DC |
| Backplane Power Consumption | 1.5 W Max (0.3 W at 5V DC, 1.2 W at 24V DC) |
| External Power Supply Required | None |
| Number of Channels | 4 (Backplane Isolated) |
| A/D Conversion Method | Sigma-Delta Modulation |
| Input Filtering | Low-Pass Digital Filter with Programmable Notch Frequencies |
| Common Mode Rejection | > 150 dB at 50 Hz / 60 Hz (for 10 Hz and 50/60 Hz filter settings) |
| Normal Mode Rejection | > 100 dB at 50 Hz / 60 Hz (for 10 Hz and 50/60 Hz filter settings) |
| Max Common Mode Voltage | ±1V |
| Max Allowed Permanent Overload | ±5V DC or ±5 mA |
| Calibration | Auto-calibration when channel is enabled or settings change |
| Isolation Voltage | 500V DC for 1 min (Between Inputs & Chassis/Backplane) |
| Isolation Between Inputs | None |
| Termination Wire Size (Max) | Two 2.5 mm² (14 AWG) wires per terminal |
| Terminal Block | Removable (Allen-Bradley 1746-RT25G) |
Environmental Specifications
| Attribute | 1746-NR4 Details |
|---|---|
| Operating Temperature | 0…60°C (32…140°F) |
| Storage Temperature | -40…85°C (-40…185°F) |
| Relative Humidity | 5%…95% (non-condensing) |
| Vibration | Meets IEC 60068-2-6 |
| Shock | Meets IEC 60068-2-27 |
| Hazardous Environment Rating | Class I, Division 2, Groups A, B, C, D |
| Certifications | UL, CSA, CE |
Input Specifications
| Attribute | 1746-NR4 Details |
|---|---|
| Supported RTD Types | Platinum, Nickel, Nickel-Iron, Copper |
| Temperature Scale (Selectable) | °C or °F (Resolution: 0.1°C or 0.1°F) |
| Resistance Scale (Selectable) | 1Ω or 0.1Ω (all ranges) / 0.1Ω or 0.01Ω (150Ω potentiometer) |
| Input Step Response | See channel step response data |
| Channel Turn-On Time |
250 Hz Filter = 388 ms 60 Hz Filter = 1,300 ms 50 Hz Filter = 1,540 ms 10 Hz Filter = 7,300 ms |
| Channel Turn-Off Time | One module update time |
| Reconfiguration Time |
250 Hz Filter = 124 ms 60 Hz Filter = 504 ms 50 Hz Filter = 604 ms 10 Hz Filter = 3,004 ms |
| RTD Excitation Current (Selectable) |
0.5 mA (for 1000Ω RTDs, 3000Ω resistance inputs) 2.0 mA (for all other RTDs, required for 10Ω Copper RTD) |