Overview
The Allen-Bradley 1746-NIO4V is an SLC500 analog combination module. This I/O module is installed on the 1746 Chassis and has 2 user-selectable (per channel) current or voltage inputs and 2 voltage outputs. The module provides differential analog input channels with flexible configuration and precise analog output generation, making it suitable for process control, sensor monitoring, and instrumentation in legacy SLC 500 systems.
Key Features
- Two differential, voltage or current selectable per channel with input signal ranges of -20 to +20 mA (or) -10 to +10V dc and two current outputs with signal range of 0 to +20 mA
- Individual switches control input mode—ON position configures for current input, OFF position configures for voltage input
- Uses R-2R Ladder Digital-to-Analog Converter (DAC) with converter resolution of 14 bits at voltage output and response time of 2 milliseconds
- Offers field wiring-to-backplane isolation at 500 Volts DC
- Single-slot mounting in a chassis without requiring terminal block removal
Technical Specifications
- Input Channels: 2 current-loop inputs with normal rating of -20 to 20mA at 250 Ohm impedance
- Voltage Input Range: -10 to 10 Volts DC with impedance of 1M Ohm
- Current Input Accuracy: ±0.642% at a drift rate of 79 ppm/5 degrees Celsius
- Voltage Input Accuracy: ±0.504%, overall drift accuracy of ±63 ppm/degree Celsius, maximum gain error of ±0.461%
- Voltage Output Range: -10 to 10 Volts
- Output Resolution: 14-bit converter
- Output Accuracy: ±0.384% of 10 Volt DC full-scale voltage, maximum drift accuracy of ±54 ppm per degree Celsius
- Overvoltage Protection: 220 Volts AC or 220 Volts DC
- Mounting: Single slot, 1746 Chassis
- Cable Requirement: Shielded Belden #8761 recommended cable, 14 AWG size
Typical Applications
The 1746-NIO4V is commonly deployed in legacy SLC 500 systems for:
- Process control and closed-loop feedback systems requiring precision analog input monitoring
- Temperature, pressure, and flow rate measurement using 4-20 mA sensor loops
- Proportional control valve and actuator command generation via analog outputs
- Multi-parameter equipment instrumentation and data acquisition
- Analog signal conditioning in machine automation and production lines
Compatibility & Replacements
Compatible With
- SLC 500 modular controllers and chassis systems
- 1746 series I/O chassis (slots 2–7)
- SLC 5/01, 5/02, 5/03, 5/04, and 5/05 processors
- Allen-Bradley RSLogix 500 programming software
- Industrial analog sensors and instrumentation (4-20 mA loops, ±10 VDC signals)
Replaces / Drop-In Replacement For
Verify compatibility with your system integrator or controls engineer before ordering. The 1746-NIO4V is a direct replacement for equivalent serial numbers and hardware revisions of the same catalog number.
Works With
- RSLogix 500 and Studio 5000 Logix Designer (with appropriate migration tools)
- SLC 500 I/O Image tables for real-time data acquisition
- Allen-Bradley industrial automation networks and hardwired field wiring
- Analog sensor networks using industry-standard 4-20 mA and ±10 VDC signal protocols
