HELP! Triggering Relay with Motion Sensor Lights

Hi, I really need some help. I want to turn on several lights in my house when the motion sensor light/camera mounted at the front door is triggered. I've opened the motion sensor light/camera and it has two very small wires going to the attached LED floodlights. I checked the voltage with a multimeter to the LED floodlights and it appears to be 70-77 volts (AC?) depending on whether they are set to dim or bright. I have been trying to learn about electronics but am clearly a novice... I thought I could use a mechanical relay that could be triggered by the LED light output (i.e., I don't need the floodlights, so I intended to cut the wires from the motion detector/camera to the LED lights and connect them to the coil of a relay). Then I'd wire the 120VAC line wire of the relevant house lights through the Common and Normally Open terminals of the relay. Also add a diode to prevent getting "flyback" or a spike going back to the motion sensor circuit. However, I can't find a mechanical relay that would "energize" the coil at 70-77 volts AC and have contacts rated for 120VAC 15 amps. Can you help? What relay should I be using and do I need to add anything other than the diode to ensure that it works and is safe? Just in case, I'll mention that the house lights that I want to turn on are a mixture of 120VAC LED lights and a couple of 12VDC lights that are connected to a 12VDC power supply connected to the same 120VAC circuit. Thanks for any and all help...

by Ronin54
January 17, 2022

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