What is a relay output?
Simple definition
A relay output is a switched contact used to control or signal another circuit.
Why it matters in wiring diagrams
Relays may be normally open, normally closed, powered or voltage-free depending on the device.
When reading a wiring diagram, this term usually affects cable choice, power path, signal path, device selection or commissioning notes.
Common mistakes
- Assuming the term means the same thing across all brands.
- Ignoring the actual terminal names in the manufacturer manual.
- Not documenting how the term applies to the final installed system.