Why do I sometimes get a periodic false trigger on motion detector?

The motion detectors are designed to look for human or animal body heat signatures.  It is possible to sometimes get what you think is a false trigger by smaller animals and it’s even remotely possible that direct sunlight or sudden changes in wind/temperature could cause a false trigger.  Care was taken to minimize these possibilities but it could occur.  Some general tips:

• Don’t put motion detection eye directly into sunlight
• Keep motion detection eye clean