On Mon, 4 Oct 2004 21:02:28 +0100, "Tom"
wrote:


Thanks for the responses, regarding signs: I enjoy the thought of making up
my own using "Printshop" as installed on my computer,(BTW, Epson printer
with latest superb long lasting inks) however I require a few appropriate
symbols to import, I can make up the words myself, it's the symbols I need.
Pump time delay: I've seen most of the commercial time delays at approx
£25 --£35 inc RS, I'm unwilling to pay that kind of dosh,

I too think they are expensive. But they are built and independantly type
tested to a standard of electrical safety (including fire), and you can
rely on that.

Write it off over 5 years or so and it's only 2-3 pints /year. ;-]

I just need a
circuit to build a delay timer based on a Triac or Thyristor, it can't be
very sophisticated as cheap bathroom fans have them,

Didn't someone post links to some .jpgs on here a couple of months ago of
a fan overrun timer PCB burning up? Ah yes:

Message-ID:

http://www.challoner.com/temp/extractor.html

all I need to do is
upgrade the power for the CH pump and decrease the time by a factor of
approx 20.

Don't go down that route, there's a good chap.

The process control delay relay has the advantage that done properly it
would be completely Kosher and all connections could be restricted to
those built into the type tested relay.

The pipe thermostat idea would also work, possibly better, and certainly
more elegant, (Providing a suitable place for the temperature sensor can
be found) but would involve more ad-hoc connections at 240v.

After all it is a DIY forum :-)

I wouldn't encourage DIY lash ups with a handful of semiconductor devices
and passive components running on 240v mains, though doubtless a solution
could be created (something like the fan controller above) for a few
pounds.

If you need to ask about it you shouldn't be doing it .

DG