A(n) ________________________ relay is a type of control relay that switches its contacts to a new state after a predetermined time has elapsed.

• A. Immediate-action
• B. Time delay
• C. Pulse
• D. Continuous

Answer: (B)

The key idea is introducing a controlled wait between the control signal and the contact change. A time delay relay is built to wait for a preset interval after the control input changes, then switch its contacts to the new state. This allows safe sequencing and prevents actions from happening at once, such as staggered motor starts or timed safety steps. It can operate as an ON-delay (delay after energizing the coil) or OFF-delay (delay after de-energizing).

Immediate-action relays, by contrast, switch contacts as soon as the coil is energized, with no intentional delay. Pulse relays produce a short, momentary change rather than a sustained delayed state. Continuous isn’t a timed-delay function; it relates to maintaining the state based on input rather than introducing a timed change.