Somehow 2.4Ghz wifi from esp8266 is triggering motion sensor. I tried shielding sensor with aluminium foil, adding capacitors… nothing helped. I googled and found that I’m not the only one.

Circuit diagram of the PIR Motion Sensor Light and Switch based on SB0061 shown here can be used for security or corridor lighting in power saving mode. ... Working of the circuit is simple and ...

The BOM on [Jeremy S Cook]’s build is extremely short – just a PIR sensor and an optoisolator, with a battery, a plug for the camera’s remote jack, and a 3D-printed bracket.

The sensor does have some limits. It can only detect motion up to about 16.5 feet away. And while Philips will give you the option of reducing that — that is, only turning on lights when motion ...

In that scenario, a simple motion detector would trigger lights when unnecessary. As a presence sensor, the FP2 can also take a step further when it comes to detail detection.

The build is a little on the expensive side at $90, but the bulk of the cost comes from the motion sensor and the power supply, two items you might have in your house already.