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How would I wire this motion sensor to the fluorescent light? I’ve heard that not all motion sensors are created equal and it may shorten the lifespan of the bulbs or possibly the transformer but if it’s a light rarely used and not much traffic thru that area, then I’m not too concerned with that... right now it’s coming straight from the breaker box and it’s on 24x7! Just stupid simple instructions to wire it... cooors have me wondering what goes to what...enter image description hereenter image description hereenter image description here

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    Can you identify the sensor? Is it just a sensor or a sensor-operated switch? If it's a switch, you just replace the wall switch with it (or leave the wall switch on and wire this in series (instead of the wall switch feeding the light, it feeds the sensor switch and the sensor switch feeds the light). See if the sensor says that it works with fluorescents (some don't, some work only with certain kinds of ballasts). My experience was that even with the proper type of ballast, the light never came on with full brightness, and quickly destroyed two ballasts. – fixer1234 Mar 25 '18 at 1:31
  • It’s a defiant replacement motion sensor... it says it’s compatible with all bulb types but I’m not sure it’s really for fluorescent lights... there’s no switch, it’s wired straight to the braker box and the only way to turn it off is to turn off the breaker in the garage (the light is in the garage)... I guess it’s the handy work of the previous owner... you can see the motion sensor on the left in the first picture... it has a red, black and white wire... I wasn’t sure how to wire it. The power cable running into the fixture has a black, white, and a copper cable which has to be the ground. – Hector Mar 25 '18 at 4:23

I found a few different models of the Defiant sensor. It looks like they all contain an electronic switch, with some controls like timing and sensitivity.

Of the models I found, some say they only work with incandescent bulbs, and some with incandescent or LED, but none claimed to be compatible with fluorescents. One of the models that claimed to work with LED bulbs had customer feedback complaining about it not working with LED bulbs. So if you use it with fluorescents, be prepared to buy a replacement ballast if it works at all.

That said, the wiring would be as follows:

  • White is neutral and gets connected in common with the white leads of the feed and the light. The feed would be a wire running back to the breaker panel. If the white is already connected to the feed, just add the white fixture wire to it.

  • The models I saw had a bare or green wire, which is the ground wire and gets connected in common with the ground wire of the feed and the ground wire of the fixture. My understanding is that if your sensor does not have a ground wire, it won't work with a fluorescent fixture (not 100% sure that is universal, or even what role it plays with the ballast, but I'll pass on that nugget for what it's worth).

  • Black is power into the sensor and is connected to the black wire of the feed.

  • Red is the power output (hot) from the sensor and gets connected to the black wire of the fixture.

If you find a similar sensor on the Home Depot web site, you can download the installation manual there. It covers not only the wiring, but how to adjust and use the controls.

  • Thank you so much for taking the time to explain this! I hjust bought it and I have the wiring diagram but I couldn’t figure it out till you spelled it out for me... I’m going to see if I can add a picture of the instructions and model! THANKS!!!! – Hector Mar 25 '18 at 6:05
  • Ditch the fluorescent fixture and put in a suitable one that can take an LED or multiple LEDs. – Jim Stewart Mar 25 '18 at 13:20

black to black(s), white to white and red to the 'lamp' 'controlled' black (the thin black wire) Ground (bare copper or green-yellow is absent because your sensor is 'class II' so doesn't need it). Wire like in this picture:

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