Add motion sensor to flood lights

Old 02-04-17, 10:21 AM
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Add motion sensor to flood lights

I have four exterior flood lights that are controlled by one switch, inside the house. When I turn the switch on they all come on. I'd like to add a motion sensor to turn them all on.

Is it possible to add a motion sensor to turn on all four lights at the same time, or would I need a sensor at each light?

I do not have access to the wiring except for what's at each fixture.
Old 02-04-17, 10:57 AM
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In a perfect situation.... the power goes to the switch, then to the first light and on to the others. So typically that would mean that the switch connects to the closest light and the motion sensor goes at that light.

However, since you have four lights.....where would one motion sensor be located that all four would need to come on ?

When it comes to wiring..... there is no "typical" method.
Old 02-04-17, 10:58 AM
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Does the switch feed the first light asnd is the other lights daisy chained from the first light?

Daisy chain:
Power in > Switch > Light 1 > Light 2 > Light 3 > Light 4

Tell us how many wires are in the switch box and each of the light boxes. (Do not include grounds in the wire count.)
Old 02-04-17, 01:43 PM
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What you need is ...

Think of a motion detector as a camera; wherever it's located, it "sees" one fixed view. That view could be the front walk-way or the shed door in the back yard, but it can't be both.

If you want to turn on all the lights when someone comes up the front walk-way, it probably won't be that difficult.

However, if you want to turn on all the lights when someone approaches the house from any direction, then you're going to have to build a "system".

Stop and decide exactly what you want to do, and then post.
Old 02-04-17, 03:11 PM
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Sorry, I guess I should have been more specific.

All four flood lights are located on the back of the house, and light up the back yard. One on each corner and two spaced equal distance between...about a 32 foot span.

So, in my perfect world, I'd like to place the sensor at one of the two middle fixtures, so that it would turn on all of the lights when motion is detected from either side. Not so much for security as it is for convenience. The boss wants the lights to turn on automatically when she takes the dog out early in the morning, when it's still dark. One light turning on would actually suffice, but I thought it would be helpful to have them all turn on.

I know how motion sensors work and I know what I want it to do, I'm just not sure if it's feasible, electrically.

I'm not sure of the wiring at the switch. I will have to check it out and then post back my findings.
Old 02-04-17, 03:47 PM
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Randy, you can install a sensor after the switch and before the first light, mounting it at a convenient place so it can "see" things move. It doesn't necessarily have to be incorporated in the lights, but maybe between. With the switch on the sensor will work normally. If you want the lights to come on and stay on, you turn the light switch off and on within one second. The lights will stay on.

Mount this in a weatherproof box

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Old 02-04-17, 04:06 PM
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OK, that makes sense Larry, so long as the other lights are daisy chained from the first light. Not sure how the electrician wired it, but I will try and find out.

The switch is around the corner on the side of the structure, inside a door. The power source is on the other side of the structure. I have a feeling that it's just a switch loop from the switch to the first light on that corner.

I think I'm beginning to get a pretty good feel for what I need to do, I just needed a little push in the right direction.

Thanks for all the help everyone!

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