House wiring question.

[GSD-Keegan]

I have outside motion flood lights that need replaced. The motion sensor is a 3 wire sensor. Red, black and white. Two switches in the house. One switch turns lights always on. The second switch turns the motion sensor on, allowing it to function and detect motion….im assuming that is the red wire. I’m having difficulty finding a new 3 wire sensor light. Can I wire the black hot directly to the bulbs bypassing the sensor, and the red hot to the sensor? The way I see it this would back feed into the sensor? What if both switches were on and the bulbs were received two hots?

 

[shelkol]

The two sources must be on the same leg of the power coming into the house.

Usually you just hook the black to the incoming power and the red to the bulbs. If you turn the switch off and back on relatively quickly it should turn the lights on and keep them on.

I have not heard of anyone hooking it up as you say, but I don't think it will hurt anything. That would be the black from the second switch to the red and bulb wire connection

 

[Roadworthy]

If you're having problems finding a three wire sensor light it's probably because the sensor is wired internally and only the hot wire for the sensor comes out for connection. This will normally be a black wire. If you open your sensor light you'll find the actual wiring to the sensor inside with the expected three wires. With that in mind you can follow the instructions above and make the new light like your old one. Normally the black wire is the hot line to the sensor and the red line is the power out of the sensor to the light. White is neutral to complete the circuit and any green wire should be grounded.

 

[GSD-Keegan]

This is how old one was wired. Red blk and white going to sensor. Two smaller gauge blk for lights with red. So I’m guessing when motion is triggered red becomes hot to turn on lights. Or when second switch is turned on red again is hot to turn on lights. So if I buy a light with only 2 wires I can wire the same? Thanks

 

[shelkol]

I guess I don't understand - what do you mean by a light with only 2 wires? If you don't have access to the red wire then you can not wire it the same way