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mattg2k4 · 01-22-2004, 08:12 PM

You might want to check what wattage bulb the nightlight is rated for, and see if your 4 cc's exceed that rating.

And as for calibrating it, its a heck of a lot easier to stick a pot on, calibrate it, and leave it set that way than to find out what the precise resistance the photoresistor is at when you want it to turn on, and then calculate the proper resistor divider. Or you could build a prototype with a pot, measure the resistance its at when calibrated, then switch it out for some regular resistors.

And yes the photo resistor would be destroyed if you ran too much current through it. However, most photoresistors have fairly high resistances IIRC, so it would not allow a destructive amount of current at 12v, but it also would not be sufficient to turn on the cc's.

Do you want to make the circuit I described? If so, I could draw up a diagram.

01-22-2004, 08:12 PM	#5
mattg2k4 Member (10 bit) Join Date: Jul 2002 Location: University of California, Santa Barbara Posts: 800	You might want to check what wattage bulb the nightlight is rated for, and see if your 4 cc's exceed that rating. And as for calibrating it, its a heck of a lot easier to stick a pot on, calibrate it, and leave it set that way than to find out what the precise resistance the photoresistor is at when you want it to turn on, and then calculate the proper resistor divider. Or you could build a prototype with a pot, measure the resistance its at when calibrated, then switch it out for some regular resistors. And yes the photo resistor would be destroyed if you ran too much current through it. However, most photoresistors have fairly high resistances IIRC, so it would not allow a destructive amount of current at 12v, but it also would not be sufficient to turn on the cc's. Do you want to make the circuit I described? If so, I could draw up a diagram.