Editing Remote terminal unit (section)

===Digital (status) inputs===
Most RTUs incorporate an input section or input status cards to acquire two state real-world information. This is usually accomplished by using an isolated voltage or current source to sense the position of a remote contact (open or closed) at the RTU site. This contact position may represent many different devices, including electrical breakers, liquid valve positions, alarm conditions, and mechanical positions of devices. Counter inputs are optional.