Product Summary
The Allen-Bradley 1746-IV8 is a discrete input module for the SLC 500 platform. It provides eight 24 Volt DC sourcing input channels in a single group. This module draws only 50 milliamps from the 5 Volt backplane. It installs directly into any single slot within the SLC 500 chassis. The module interfaces with auxiliary contacts, limit switches, and sensors. It delivers reliable change-of-state detection for your control program.
Expert Technical Evaluation & Performance Review
Signal Processing and Timing Accuracy
The 1746-IV8 module delivers consistent performance with a signal delay of exactly 8 milliseconds for both ON and OFF transitions. This predictable timing allows engineers to design precise control logic. The module accepts an input voltage range from 10 to 30 Volts DC. Its nominal input current sits at 8 milliamps when operating at 24 Volts DC. This combination ensures stable signal reading from a variety of field devices.
Electrical Characteristics and Isolation
The module operates as a current sourcing DC input type. It requires a minimum input voltage of 10 Volts DC to register an ON state. The off-state voltage must not exceed 5.0 Volts DC. The off-state current remains below 1 milliamp. These thresholds prevent false triggering from electrical noise. The backplane current draw is only 50 milliamps at 5 Volts DC. This low consumption allows for more modules in a single chassis.
Environmental Tolerances for Industrial Use
The 1746-IV8 withstands harsh industrial environments with ease. Its operating temperature range spans from 0 to +60 degrees Celsius. The storage temperature extends from -40 to +85 degrees Celsius. It operates reliably in relative humidity levels from 5 to 95 percent without condensation. This module is supplied as open-type equipment for industrial settings. It requires installation within a suitable enclosure for protection.
Wiring and Termination Standards
This module requires 14 AWG cables for signal termination. The cables should have a maximum diameter of 2 millimeters. Each channel connects to sourcing type field devices. The front panel provides LED indicators for each input channel. These LEDs show the current state of every connected device. This feature simplifies troubleshooting during system startup and maintenance.
Installation Best Practices for Longevity
Always remove power from the rack before installing or removing this module. Electrical arcing can damage the module and its connector contacts. Worn contacts create electrical resistance and reduce system reliability. The module occupies only a single slot in the SLC 500 chassis. The host processor limits the total number of module instances. Consider both slot availability and processor I/O capability when planning your system.
Logistics & Standard Packaging Details
- One Allen-Bradley 1746-IV8 SLC 500 Input Module
- Product documentation and installation guide
- Anti-static packaging for safe transport
- Express delivery shipping via FedEx, UPS, and DHL
