On Tue, 06 Jan 2004 00:04:07 +0000 (GMT), Dave Plowman
wrote:

In article .uk,
Ed Sirett wrote:
Low power 555's handle minutes without problems, but this application
probably only really needs around 10 seconds, and it doesn't need to
be accurate.

Wouldn't a slow release relay/contactor be suitable?

You can buy variable delay relays from RS etc, but they're far more
expensive than making your own.

I used a multifunction electronic staircase timer (RS 277-3520) - £18;
for a similar application.

It seemed to me that by the time I had bought the bits, put them
together, got a small power supply, put the whole lot in a box, it
would approach this on parts before considering the time taken.

..andy

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