Light/ Dark sensor with delay circuit , HELP !

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Im new to this, im trying to add a delay circuit on my project. I have connected a diode to be lit by the relay, now it is turning on instantaneously when dark and i need to add a delay circuit such that when it is dark, the light may remain on and when light falls, the light may stay on controlled by a timer . I need to be able to adjust the delay period.

thanks

Please help with some schematic extension . Im stressed !

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The basic operation of this circuit is to turn on a lamp when is is dark. But when daylight strikes, i need the lamp to stay on depending on infinitive period

How did you manage to make a blank post?

Very impressive, the forum software doesn't normally allow you to do that.

What do you mean by delay?

If you just want a delayed response then connecting a large capacitor (470µF) across R1 would achieve that.

Giggabite said:

The basic operation of this circuit is to turn on a lamp when is is dark. But when daylight strikes, i need the lamp to stay on depending on infinitive period

Click to expand...

Easy to make

Get a relay with another set of switched contacts (2 or more sets of contacts)

Conect a 10K resistor with a make contact (from the relay) from the +12V to the Base of the transistor, this will switch the transitor on until it is reset.

Put a reset contact in this line that is controled by hand or timer to reset the devise to "automatic ON switching" state

Robert-Jan