Connecting a photocell

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  #1  
Old 04-09-16, 10:02 PM
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Connecting a photocell

Hello,

I have a quick project that has me scratching my head. The ballast in my coke machine is bad so I decided to use 12v LEDs that I have laying around. How ever, I didnt want them to be on 24/7. So I bought a 12V DC or AC Photocell off Ebay.

The problem is that I cannot get it to work correctly. I have searched the internet and youtube with out much luck. Heres what I wanted to do.

I was going to have the 12vdc power supply feed the photocell and the photocell feed the LEDs.

Only issue I have is the instructions for the photocell are all in Chinese. It has 3 wires, Black Red and White.


Can some one tell me how to hook this up? I know in VAC is RED & Black are HOT and White is Neutral, Green is ground.. But this has me a little stumped.

Appreciate any feedback.

Bryan
 
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Old 04-09-16, 10:17 PM
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Black Red and White
Sounds like 120 volt AC photocell but if 12 volt Line goes to black and white of the photocell and load to the red of the photocell and the white.
 
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Old 04-10-16, 07:29 AM
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I agree with Ray. If it's a 'standard' photocell that you'd use on an outdoor light, it is designed to work at 120v, and likely won't work at 12v.

I would connect it before the power supply. Usually the black and white connect to the main power, then red (and all 3 whites) connects to the load (light bulb/power supply).
 
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Old 04-10-16, 10:35 AM
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Hi Ray,

Thank you for your response. I am a little confused about your answer. You said to take Pos and Neg from power supply and hook it to black and white of the photocell, and red of the photocell goes to the LEDs. But I'm a little confused about the last part of the sentence. If I hook the white wire to both power supply and and load. Wont that cause a short?

The power supply have only 2 wires. black and red. (Pos and Neg)

Here is a link to the item I purchased...

2X Auto on Off Switch Control 12V 10A Street Light Photocell Photoswitch Sensor | eBay
 
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Old 04-10-16, 10:41 AM
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How are you powering the 12v LED's ? It should be some type of 120v to 12vdc power supply.

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Last edited by PJmax; 04-10-16 at 01:19 PM. Reason: corrected diagram
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Old 04-10-16, 01:00 PM
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You said it was a 12 volt power photocell but I doubted it was given the colors you had. That is why I asked if you are sure it is a 12 volt.
You said to take Pos and Neg from power supply and hook it to black and white of the photocell,
No because only one side is switched. If you switch the positive and assume black and red are positive then your positives go to those and whites are negatives. How ever since the colors are not that of a 12 volt photocell no way to know. I really think you have a 120 volt AC photocell.
 
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Old 04-10-16, 01:20 PM
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I corrected my post. I had thought 120v photocell. The new diagram reflects 12vdc operation.
 
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Old 04-10-16, 01:27 PM
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But since we don't know if it is a 12 volt photocell and if it is which is positive and which is negative we are only guessing. (At least I am. I can't say for Pete.)
 
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Old 04-10-16, 01:47 PM
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He posted a link to the one he got. I find it strange that it works on 12v AC and DC.

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Old 04-10-16, 03:28 PM
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Even stranger white is marked neutral. A 12 volt supply AC or DC doesn't have a neutral. Wonder if 12 is a typo and should be 120.
 
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