What is a dry contact?

A dry contact is an electrical circuit that does not carry any voltage or current. It is typically used to provide an interface between different systems or devices, allowing them to communicate without actually connecting their electrical circuits. Dry contacts are often used in relay systems, security systems, and automation controls.

One common example of a dry contact is a relay switch, which opens and closes a circuit without actually carrying any electrical current. When the relay is energized, it closes the circuit and allows electricity to flow through it. When the relay is de-energized, the circuit is open and the flow of electricity is interrupted.

Dry contacts are often used in situations where it is not safe or practical to directly connect electrical circuits, such as in high-voltage systems or in situations where different systems need to communicate with each other without sharing a common ground. By using dry contacts, these systems can communicate effectively while maintaining isolation and safety.