Motion sensor instructions says one sensor per switch, Why?

[keane1]

Hi. I'm new to the board and have two questions about security lighting with motions sensors.

1) I have 2 new LED security lights and 2 new motion sensors. The instructions says to only install one sensor per switch. Both lights are on the same switch and I want a sensor on each light, one in front of the house and one in back. Is there any valid technical reason to only have one motion sensor on the same switch?

2) The lights are 100 watt LED each. So 100 watts per sensor. The sensor says 500 watts incandescent/tungsten/halogen or 50 watts LED. Again is there a valid reason why the sensor can only handle 10% of the load on LED lighting?

Thanks for you help.

 

[brianmoooore]

Can't see any reason why you shouldn't connect sensors in parallel.
I would expect the sensor to be derated for LED use, because of the greater inrush (surge) of current at switch on, but 90% seems excessive.

 

[keane1]

Should I consider adding a relay. Let the motion sensor control the relay and the relay turn to power on?

 

[Avo Mk8]

If the motion sensors are purely solid-state, ie no relay inside, and you connect them in parallel, when one switches on it may prevent the other from switching on.
At least for solid state switches this is true, as apparently they need a voltage across them to operate!