I have a porch light with a motion sensor outside the sliding doors leading to my backyard deck. It is on the same circuit as the lights in the kitchen.
When the kitchen lights are turned on the porch light will also come on. It will act normally after that.
Any ideas?
Yep, incandescent lamps take a high initial current that causes a transient on the supply lines.
The transient hits the control electronics on the motion sensor.
The motion sensor electronics cannot tell the difference between a transient on the supply lines and a signal from the sensor - so operates.
Solution 1 is to stick a mains filter on the power lines going to the sensor. A couple of ferrite cores and a capacitor should do nicely.
Before I tried anything too exotic I would be sure this wasn't just a loose connection somewhere in that circuit. (wirenuts or backstabbed devices are the first place to look) Sue is right, any dip in the line will trip the sensor. An AM radio will probably have static on it when you tap the bad device with your knuckle while the lights are on. You may even see the light flicker..
Are some such devices not made to light on first being powered up, so as to act both manually and automatically?
John
Not worth the trouble. The porch light comes on for 4 minutes and then shuts off.
Thanks for the help.
In what circuit are you referring? I checked the connections on the switches that control the porch light and they were o.k. I just replaced the porch light so I know those connections are o.k. as well.
Now for the kicker. The house has aluminum wiring (built in 1972). I have checked all the connections and even brought in an electrician to check out the main panel. Everything is tight but I suppose that could be a source of the issue.
Turns out not just incandescent lights turn on the porch light. The overhead fixture in the dining room and flood light above the sink also turn it on.
all that is happening is a surge on the lighting circuit is affecting the cheap electronics in the motion sensor.
If they are all on the same breaker I would think more about that loose connection.
You must be referring to a possible loose connection at the light (maybe with internal electronics).
Or the obvious solution is to check that you are not switching the neutral wire, this would have the same effect
Checked the two switches and they are wired correctly. Either it is something to do with the combination of sensor electronics and the aluminum wiring in the house. I am going to check the other connections on the entire circuit.
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