Photocell programming???

[powerplay]

I have installed a few photocells before but for an 400W Metal Halide fixture, it didn't work and I was told it had to be programmed. Does the photocell need to be "trained" to recognize the difference between day and night? I had installed the Intermatic K4221C in an box ahead of the fixture. The wall faced south so I faced the photocell eye towards the building. I had the power to the black, red to the load, white to common. I was told to put black tape on the eye, then remove it at nighttime...someone tried it and apparently it worked, but I never heard or read that before. Fact or fiction??

Thanks...Powerplay

 

[qcroanoke]

I have installed a few photocells before but for an 400W Metal Halide fixture, it didn't work and I was told it had to be programmed. Does the photocell need to be "trained" to recognize the difference between day and night? I had installed the Intermatic K4221C in an box ahead of the fixture. The wall faced south so I faced the photocell eye towards the building. I had the power to the black, red to the load, white to common. I was told to put black tape on the eye, then remove it at nighttime...someone tried it and apparently it worked, but I never heard or read that before. Fact or fiction??

Thanks...Powerplay

That's how I test them. Leave the tape on long enough to make sure the light comes to full brighness then remove the tape so it will turn off.
Some photocells will turn the light on on initial power up also but will go off as soon as it sees enough light to turn the light off.

 

[powerplay]

That's the trick, I installed it when the sun was setting, so i used my LED flashlight to simulate daylight but the light didn't turn off. I may have hooked it up in reverse, but was sure the power was hooked to black...if it was reversed would it not turn off? The point that puzzled me was that someone said it needed to be trained to discern night from day....the photocell simply uses energy from light to create an barrier to prevent power from reaching the load doesn't it? This person said to tape the photocell during the day, then take it off at night and it would work...sounds like too much work to me

 

[lakee911]

That's the trick, I installed it when the sun was setting, so i used my LED flashlight to simulate daylight but the light didn't turn off. I may have hooked it up in reverse, but was sure the power was hooked to black...if it was reversed would it not turn off? The point that puzzled me was that someone said it needed to be trained to discern night from day....the photocell simply uses energy from light to create an barrier to prevent power from reaching the load doesn't it? This person said to tape the photocell during the day, then take it off at night and it would work...sounds like too much work to me

LED puts out a specific wavelength of light. If the photosensor wasn't designed for that wavelength it may not see it. Try an incandescent bulb ...

 

[qcroanoke]

I may have hooked it up in reverse, but was sure the power was hooked to black...if it was reversed would it not turn off?

If it was wired backwards the light would cycle on and off until you corrected the wiring.
At least any I have seen wired wrong did........

 

[steve66]

I don't think photocells need to be trained. But some do have a sensitivity adjustment. Others have a sensitivity adjustment that basically a cover that you can adjust how much is let into the photocell.