Some typical types of input modules are listed below.
* DC voltage (110, 220, 14, 24, 48, 15-30V) or current (4-20 mA).
* AC voltage (110, 240, 24, 48V) or current (4-20 mA).
* TTL (transistor transistor logic) input (3-15VDC).
* Analog input (12-bit).
* Word input (16-bit/parallel).
* Thermocouple input.
* Resistance temperature detector.
* High current relay.
* Low current relay.
* Latching input (24VDC/110VAC).
* Isolated input (24VDC/85-132VAC).
* Intelligent input (contains a microprocessor).
* Positioning input.
* PID (proportional, integral, differentiation) input.
* High-speed pulse.
