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How to replace light bulb load in a motion sensor circuit? Answered

I am using a outdoor light replacement motion sensor to trigger a relay which will turn on a fog machine for some Halloween effects. The setup is pretty simple and I am going to enclose the components in a project box so the motion sensor can be hidden near the walkway to my house.

My problem is the motion sensor requires the load of a light bulb in the circuit to operate so that the relay can be engaged but I don't want to have a light since this is suppose to be hidden in the dark. My first thoughts were to just replace the bulb with one or more resistors in the circuit but I am not sure if this will be possible or dangerous (in terms of heat).

How should I set up the relay circuit to have a load but not have a light bulb? Since my timeline to get this complete is the next couple days for Halloween I need to find options which I can source locally (radio shack, home depot, etc.). Any thoughts?


i am asuming that your fog machine is 110V.  Just hook up the fog machine to the internal relay of the motion light.  We did something like this for a project.  Except we needed 5V out.  Anyways all the motion sensor is, is a relay that when tripped turns on lights just replace lights with fog machine.  only problem i see is that fog machines take time to work (heat up).

You're correct, the fog machine is 110V. My initial plan was to just use the motion sensor relay but for some reason I couldn't figure out how to properly connect it to the fog machine circuit. Which is why I went this direction.

I just need something that can replace the light bulb load that doesn't cause heat problems or create a big light source.

I am considering a cell phone charger as the load for the short term. They are small, and don't put out much heat. It could act as the load.