The Allen Bradley 1746-IV8 is one version of the SLC 500 Digital Input Module series. It comes with 8 channels and a voltage capacity of 24 Volts DC. The 1746-IV8 module can also be referred to as a Current Sourcing DC Input Module. Its terminal has a self-lifting plate that receives two 14 AWG (2 millimeter) cables and LED indicators on the front. The operating voltage range of this module is from 10 to 30 Volts DC while the backplane current of this module at 5 Volts is 50 mA, and 0mA at 24 Volts. In its “off” state, the 1746-IV8 has a maximum input voltage of 5 Volts DC. The maximum signal ON delay of this module is 8 milliseconds; the maximum signal OFF delay of is 8 milliseconds.

The 1746-IV8 is supplied as open type equipment, intended for use in industrial environments. Stop power before removing this module. Removing or inserting a module with power applied can cause an electrical arc to occur, which can cause personal injury. Electrical arcing can also cause excessive wear to contacts on both the SLC 500 module and its mating connector. Worn contacts may create electrical resistance which can lead to reduced product reliability.