1746-NR8

Overview

1746-NR8 is an 8-point RTD/resistance input module from Allen-Bradley’s SLC 500 series.
It supports high-accuracy temperature and resistance measurements with auto-calibration and advanced digital filtering.

Power Requirements

• Backplane Current (5V DC): 100 mA

• Backplane Current (24V DC): 55 mA

• Backplane Power Consumption: 1.82W max (0.5W at 5V DC, 1.32W at 24V DC)

• External Power Supply: Not required

Input Configuration

• Number of Channels: 8 (backplane isolated)

• A/D Conversion Method: Sigma-Delta Modulation

• Input Filtering: Low pass digital filter with programmable notch frequencies

• I/O Chassis Location: Any I/O slot except slot 0

Signal Performance

Common Mode Rejection

• 120 dB at 50 Hz (28 & 50 Hz filter)

• 120 dB at 60 Hz (28 & 60 Hz filter)

Normal Mode Rejection

• ≥ 65 dB at 50/60 Hz (with 50/60 Hz filter)

• ≥ 110 dB at 50 Hz (with 28 Hz filter)

• ≥ 95 dB at 60 Hz (with 28 Hz filter)

Max Common Mode Voltage

• ±1 V

Max Permanent Overload

• ±5 V DC or ±5 mA

Input Frequency Response

Filter Cut-Off Frequencies:

• 7.80 Hz @ 28 Hz filter

• 13.65 Hz @ 50/60 Hz filter

• 209.6 Hz @ 800 Hz filter

• 1676 Hz @ 6400 Hz filter

Calibration Features

• Startup Calibration: Auto-calibrates at power-up

• Periodic Calibration: Optional every 5 minutes

Isolation Ratings

• Input–Chassis & Input–Backplane: 500V AC for 1 minute

• Channel-to-Channel Isolation: 5V DC continuous

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