How is a dry contact best described?

A dry contact is best described as a relay output. This term refers to a switch or relay that does not provide any voltage or current on its own; instead, it acts as a contact that can be closed to facilitate the flow of electricity from an external source.

When the relay is activated, the contacts close, allowing current to pass through from an external circuit without imposing any voltage or current of its own. This makes dry contacts versatile in various applications since they can control different devices or systems across many voltage types and levels without interfering with the circuit they control.

In different contexts, a dry contact can be used for signaling in alarm systems, control panels, or interlocks, among others, often providing an isolated way to interact with other devices. Understanding this concept is critical for anyone working with or designing systems that utilize relays for control purposes.