Time delay relay

curious_mind

Member level 5
I have high reliability hermetically sealed relay and all I have to do is to convert it to a timer relay. I have two questions

1. How do I design high reliability timer circuit?
2. How to make it configurable (say 1 to 60 s )

I do not want to use MCUs

barry

Advanced Member level 5
1) How do you define "high reliability"? Is it exposed to radiation? Vibration? Temperature extremes? That's a REALLY vague question.
2) You could use a 555 timer, or any number of other timing devices whose output drives a transistor which then drives the relay coil.

andre_teprom

Super Moderator
Staff member
Hardly achievable unless by using a number of discretes devices and integrated circuits, as 4060, 4017, crystal oscillator, etc...

curious_mind

Member level 5
I meant reliability with respect to temperature (industrial grade) and timing acuracy

barry

Advanced Member level 5
You still don't give us anything to go on. What KIND of accuracy? Yoctoseconds?

Brian.

barry

Advanced Member level 5
Yes, a cheap MCU would do it. But, again, if OP only needs one of these then the cost of an off-the-shelf solution versus the cost of design-build-code-test-debug is orders of magnitude cheaper. Unless you work very cheaply.