[SOLVED] LED bulbs won't turn off in outdoor light/motion sensor base.

[Thankful]

replying to trader_4, Thankful wrote: The one incandescent bulb did the trick on a sensor-ed system. Thanks

[trader_4]

Always good to hear that suggestions worked. Thanks for letting us know.

[gfretwell]

It depends on the design. If it has a relay in it, the bulb type does not matter.

[TimR]

According to the kill-o-watt meter I tested with, incandescents have a power factor of 1.0, while CFLs and LEDs were running at 0.6.

Just throwing it out there, I don't know what kind of circuit that would be a problem for, if any.

[Mike_Duffy]

Power factor of the load is not relevant. The original problem was that many models of motion-activated light switches use the load as a virtual ground for the sensor circuit. Thus there is always a small current flow through the load while the sensor is checking for motion.

Full current is applied when motion is detected, and the small continuous flow while it is 'waiting' is not enough to light an incandescant bulb.

But it *is* enough to light the much more efficient LEDs. Thus they end up being slightly 'on' while no motion is detected. Because of the design of the AC power supply in the base of the LED that convert & filters the current for the LED, often they will blink very fast instead of lighting up very dimly.

[Mark Lloyd]

[snip]

Also, LEDs don't have to heat up to produce visible light.