> Hi Harold. We use about 1,000 Amperite time-delay relays a year (110Vac
> 8sec
> SPSP NO). IIRC we pay about $14 each for them. The timing is not very
> precise on these. Our spec is 8 seconds, we test to make sure the units
> are
> between 3 - 15 seconds and we still get about 5% duds. I think Amperite
> makes "flasher" modules too. Although we use a lot of Amperites, I am not
> a
> big fan of these devices - they are a necessary evil in our application.
>
> Maybe you could use a timing motor, cam, and switch to get the desired
> timing? Or maybe somehow use a switch tied to one of the solenoids - the
> solenoids wont pull-in instantaneously so maybe you could get your delay
> from that. They probably take less than 0.5 sec though. In either case not
> very elegant.
>
> Sorry, that's the best I can suggest. Maybe somebody will come up with a
> clever solid state way to do this.
>
> -- Mark
>

THANKS! I used the Amperite relays 30 years ago and had no idea what the
current cost was. A couple limit switches on the solenoids would be a nice
simple solution, but we'd have would have almost no control over the
timing. As I was writing this, I got a call from another thermal time
delay manufacturer. I think they said price would be aout $7.50 in the 1k
quantity range, but they cannot go below 1 second. They generally run
about 8 seconds. A high voltage DC astable multivibrator is looking
better!

Harold


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