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Help me build a simple delay off timer

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mikesmixes

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I need to build a simple delay off timer. When the input is triggered (pulse only) the output must go high and stay high for a period of say 1 hour or 4 hours or selectable. When the input is triggered again, the output timing is restarted.

Any idea's? Would a 555 timer work? Not sure about the long delays.
Supply is 24Vdc.

Thanks.
Mike
 

VVV

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Re: Delay off timer

Yes, the 555 would work. The time delay required is rather high, though. That means you have to use a good quality cap. The CMOS version of the 555 would be more suitable.

You will also need a regulator, since the supply voltage is 24V and the 555 cannot work at that voltage.
 

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