Digital Timers
are like clocks, keeping track
of timing; to trigger
an action, to start
timing once triggered
by an action , or
both. Some are programmable
while others may have a
fixed internal time
and function.
Suppliers of Digital Timer offer
many different types, which
include:
- Timer Meters - They are used in applications for display of elapsed process time or tracking running time of factory machinery.
- Delay-on Timers – These timers require a predetermined period of time to pass between when the timer receives the input signal and when the output is energized. When the time delay ends, the contacts open or close. At the end of time period, the load energizes if the contact is normally open (NO) and when it is normally closed (NC), the load de-energizes. The time delay and output can be reset by removing power.
- Delay-off Digital Timer
– These timers start
their timing functions
when the power
supply is interrupted. When the
power supply is
removed, the output relay
contacts stay activated
and the time
period starts.
- One shot Timers - Also called pulse formers, these timers are designed so that when power is applied, the contacts change position immediately and remain so for the set period of time after the timer has received power. After the set period is over, the contacts return to their normal position.
- Interval Digital Delay Timers – These timers are the opposite of delay-on ones. The relay is energized immediately upon the application of the supply or closure of the switch input, and going off at the end of the period.
- Recycle Timers - These timers work in such a way so that the closing of the control switch starts the cycling function. For as long as the control switch is closed, the load continues to turn ON and OFF at regular time intervals. When the control switch is open, the cycling function stops.
