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Ed Sirett
 
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Default Central heating Pump Overrun

On Sun, 04 Jan 2004 23:35:57 +0000, Andrew Gabriel wrote:

In article ,
Steve writes:
geoff wrote:


A microcontroller just to give you a 2 minute delay - bit of an overkill
isn't it ?


Cheap enough these days, and about 30 seconds of programming effort. Why
ponce about with 555 timers (flaky at long delays) ?


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?


--
Ed Sirett - Property maintainer and registered gas fitter.
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