Description
The Allen-Bradley 1746-NO4I is a 4-channel analog output module designed for the SLC 500 programmable logic controller platform. This module provides four current-based output channels, specifically engineered for precision control of external industrial devices such as actuators, valves, and variable frequency drives. It is optimized for integration within the 1746 chassis and features high-resolution output capabilities to ensure accurate process regulation.
Features
- Four (4) independent current output channels
- 14-bit high-resolution output for precise control
- Configurable output ranges: 0 to 20 mA or 4 to 20 mA
- Galvanic backplane isolation for signal integrity
- Fast dynamic response times suitable for demanding control loops
- Supports external power switching for application flexibility
Applications
- Water and Wastewater Treatment: Controls dosing pumps and valves based on flow or level setpoints.
- Food and Beverage Production: Manages pasteurization temperatures and conveyor speeds.
- Chemical and Petrochemical: Provides high-precision PID control for reactor pressure and temperature.
- HVAC and Climate Control: Regulates dampers and cooling tower fan speeds.
- Metals and Mining: Controls hydraulic press pressure and positioning.
Technical Specifications
| Parameter |
Specification |
| Product Model |
1746-NO4I |
| Series |
SLC 500 |
| Output Channels |
4 |
| Output Current Range |
0 to 20 mA |
| Full Scale Output |
21 mA |
| Overrange Capability |
5% (0 to +21 mA - 1 LSB) |
| Backplane Current (5V) |
55 mA |
| Backplane Current (24V DC) |
195 mA |
| Operating Temperature |
0 to 60 degC |
| Storage Temperature |
-40 to 85 degC |
| Field Wiring Isolation |
Up to 500V DC |
Installation Guidelines
- Ensure the SLC 500 chassis is powered down before inserting or removing the module to prevent electrical damage.
- Use shielded cables, such as Belden #8761, to maintain signal integrity and minimize EMI interference.
- Maximum permitted wire size for terminal connections is #14 AWG.
- Ensure proper grounding of the cable shield at the source to prevent ground loops.
- Maintain adequate ventilation within the enclosure to keep ambient temperatures within the 0 to 60 degC operating range.
- Handle with care to prevent electrostatic discharge (ESD) damage to the module circuitry.
FAQ
What is the Allen-Bradley 1746-NO4I?
The 1746-NO4I is a legacy 4-channel analog current output module for the SLC 500 PLC platform, designed to convert digital data into analog current signals for process control.
What type of signals does it output?
It provides four current-only output channels with a range of 0 to 20 mA.
What is the load resistance range?
The output circuits are designed to handle a load resistance of 0 to 500 ohms.