Time Delay Relays

 Time Delay Relays

The time-delay relays are used for performing timedelayed switching operations such as starting, protecting and controlling circuits applications. 

This relay consists of a relay mechanism with a control circuit wherein the control circuit is made with solid state components and timing circuits so that a control operation with a predefined-timing range is

performed. 

This time-delay function includes on delay, off delay, repeat cycle, one shot, re-triggerable one shot, pulse generator, on or off delays, etc. 

A special type of such relay is a star-delta wherein within a certain time period it changes the terminal connection Along with the above types, time-delay relays can also be differentiated depending on normally open or normally closed contacts with the time delay in the direction of closing or opening. 

These are of different types like normally-open timed-closed contact (NOTC), normally-open timed-open (NOTO), normally-closed timed-open (NCTO) and normallyclosed timed-closed (NCTC) contact type relays.

Depending on the function, these time relays can also be triggered or initiated either with the application of a trigger or input voltage. 

These initiated signals can be controlledswitch-like push button, limit switch, float switch, etc., or simply a power trigger with

voltage excitation.