MPN

Timer Relays

What are Timer Relays?

A Timer Relay is a control relay with a time delay function built in. They serve as a combination of an electromechanical output relay and a control circuit, in which contacts can be opened or closed before or after a pre-selected timed interval. Relays can be normally open or normally closed and can be used to delay timed functions from milliseconds to hours or even days.

Timer Relay or Electromechanical Relay?

The difference between the timer relay and electromechanical relay is that when the output contacts open or close. On a conventional Control Relay, the contacts are opened or closed when a voltage is applied and removed from the coil, however, for timer relays the contacts will open or close before or after an intentional time period. When choosing the right Timer Relay, it is important to consider the kind of delay required for your application.

What are the Types of Timer Relays?

The most common timing function of Delay Relay are:

On Delay (Time delay starts on the application of voltage)
Off Delay (When a voltage is applied the relay is ready to accept a trigger)
Single Shot (One-shot)
Interval On (Interval) and Flasher (On First / Off First)
Repeat Cycle (When a voltage is applied the relay contacts change state and the timer starts)

When designing your application, it is important to understand the difference between the types of the Timer Delay Relays, considering what should initiate the delay and if it should start at the same time as the application, as well as when the voltage is released. More information can be found in our Timer Relays Guide

Timer Relays are triggered/initiated by either:

Voltage being applied or
The closing or opening of a trigger signal

Applications of Timer Relays

Delay Relays are typically used in industrial applications and OEM equipment play an important role for many industrial processes such as small panel or sub-panels requirements.