Use it to check the state of switches and push buttons, and/or to switch relays, solenoids, and LEDs.
Digital Inputs
The Digital Inputs are activated by an external voltage source, triggering on a wide voltage range: 4 to 30VDC. They provide built-in filtering, to eliminate false triggering from electrical noise. They can be used to convey the state of on/off devices, such as push buttons, limit switches, relays.
Digital Outputs
The Open Collector Digital Outputs can be used to directly control substantial devices, switching up to 30VDC at up to 2 Amps. The Output acts as a switch to ground, so the circuit you're switching will need an external power supply. Each output is protected from transient voltages typical when switching inductive devices - relays, solenoids, motors. The Outputs can be used to directly control devices requiring substantial power such as incandescent lights, high power LEDs, relays, solenoids, motors.
