Overview
The Allen-Bradley 1746-NO4I is a four-channel analog output module designed for the SLC 500 programmable controller family. The module uses a 16-bit 2’s complementary binary format and provides output currents in the range of 0 to +20 mA with full-scale current output of 21 mA. This module is ideal for process control, machine automation, and systems requiring precise analog signal generation to drive proportional valves, actuators, and industrial instrumentation.
Key Features
- Four Independent Output Channels: Four current output channels providing an output range of 0 to +20 mA
- 14-Bit Resolution: 14-bit resolution for accurate signal representation
- Fast Update Response: 512 µs update response time for all channels operating in parallel
- Dual Power Options: Connections for user-supplied 24V dc power supplies; when external 24V dc power is used, the module only draws 5V dc current from the SLC backplane
- Backplane Isolation: 500 Volts DC backplane isolation for signal integrity and protection
- Industrial-Grade Design: Screw-terminal connections and proven reliability in manufacturing and process control environments
Technical Specifications
- Output Type: Current loop (non-isolated)
- Output Channels: 4
- Output Range: 0 to +20 mA with full-scale output of 21 mA
- Resolution: 14-bit
- Update Time: 512 microseconds
- Load Resistance: 0–500 ohms
- Backplane Current Draw (5V DC): 55 mA
- Backplane Current Draw (24V DC): 195 mA
- Power Supply Voltage: 24 Volts DC ±10%
- Operating Temperature: 0 to 60 degrees Celsius
- Storage Temperature: -40 to 85 degrees Celsius
- Relative Humidity (Non-Condensing): 5 to 95%
- Mounting: Single-slot SLC 500 chassis module
- Series: Series A
Typical Applications
The 1746-NO4I is a 4-channel analog output module designed for the SLC 500 control platform, providing current-loop output signals for controlling industrial devices such as valves, drives, actuators, and instrumentation requiring 0–20 mA signals. Common uses include:
- PID loop control outputs
- Proportional valve actuation
- Pneumatic and hydraulic positioner control
- Motor speed control via 4–20 mA reference signals
- Process instrumentation and data logging
- Machine automation and equipment sequencing
Compatibility & Replacements
Compatible With
- SLC 500 fixed and modular chassis
- SLC 500 processors (all Series)
- Standard SLC 500 power supplies (1746-P1, -P2, -P4)
- External 24V DC power supplies (24V ±10% tolerance)
- RSLogix 500 programming software
- Standard industrial control networks via SLC communication adapters
Replaces / Drop-In Replacement For
The 1746-NO4I is comparable with the 1746-NO8I (which has more output channels); when it comes to cost effectiveness, the 1746-NO4I costs lower than the 1746-NO8I, and functionality and configuration methods are identical for both modules. Direct compatibility with existing 1746-NO4I installations ensures seamless upgrades and replacements.
Works With
- RSLogix 500 controller programming
- SLC 500 I/O configuration tools
- Standard 4–20 mA field devices and instruments
- EtherNet/IP gateways via SLC communication adapters
- Multi-chassis SLC 500 systems
