Relay turn-off time

Usually listed in the specs somewhere.

I've measured an average of 15mS for a quantity of the type known as 'Continental Cradle' relays. That was with a diode directly across the coil.

Thanks for the info. The data sheet for the relay did not have this information.

BRW

You can measure this, very roughly, by wiring up the relay as a buzzer. I usually get frequencies between 200 and 800 Hz.

I'm curious as to why you're asking this question.

Specs are specs, but while I don't know of a way to speed the drop-out of the contacts, a simple diode and series resistor across the coil is very effective in slowing the drop-out, as is "slugging".

Also, there is no typical "small ice cube" relay. Performance specs are dependent on both the manufacturer and relay model number. (These are usually available on the manufacturer's web site.)

If you have no specs available, you simplest solution (as another poster has already suggested is the wire the relay as a buzzer and measure the frequency. This should be sufficient to give you +/- 10% estimates of the dropout time.

Harry C.