Odd LED floodlight problem

[ImpededLoop]

A couple of months ago I installed two LED floodlights. One is 10W, the other is 30W. They are both connected to the same PIR and each light is no more than 400mm from the PIR.

Everything works when installed, but within a few days the 10W floodlight stops working. I've replaced it four times, most recently with a light from a different manufacturer. Within three days it's stopped working again.

I'm now intending to replace the 10W floodlight with one that has it's own PIR. However I'm curious to find out what the cause of the failures is. I must confess that I haven't tested any of the units that I assumed to have failed. There's definitely no wiring fault and the PIR and 30W floodlight have always worked perfectly.

Cheers.

 

[Dozer 73]

Just to follow this up, I visited the job again and found that the 10W LED floodlight had indeed failed and didn't work when connected to a 230V supply.

The PIR definately has a relay, is rated upto 1200W (I know LED's will have a high inrush current) and is still switching the 30W floodlight with no problems.

My gut feeling is the cause of the problem was something to do with the 30W and 10W floodlights being wired in parallel from the same PIR and therefore energising at exactly the same time; somehow damaging the 10W floodlight, on each occasion, within days of installation.

I've now installed a 10W floodlight with it's own PIR and am confident that the problem won't now reoccur!

Thanks to everyone who replied.

Strange fault that one , costly too I presume

 

[ImpededLoop]

Strange fault that one , costly too I presume

Luckily the lights were exchanged each time and I can access the job at any time so the only cost was my time. Still a pain though but intriguing too!

 

[GeorgeCooke]

Just to follow this up, I visited the job again and found that the 10W LED floodlight had indeed failed and didn't work when connected to a 230V supply.

The PIR definately has a relay, is rated upto 1200W (I know LED's will have a high inrush current) and is still switching the 30W floodlight with no problems.

My gut feeling is the cause of the problem was something to do with the 30W and 10W floodlights being wired in parallel from the same PIR and therefore energising at exactly the same time; somehow damaging the 10W floodlight, on each occasion, within days of installation.

I've now installed a 10W floodlight with it's own PIR and am confident that the problem won't now reoccur!

Thanks to everyone who replied.

LEDs don't have a high inrush current.

There is no reason why two different sizes of LEDs in parallel on the same PIR could damage one of them.

 

[ImpededLoop]

LEDs don't have a high inrush current.

I've always understood that they do.

There is no reason why two different sizes of LEDs in parallel on the same PIR could damage one of them.

A few weeks ago I would have agreed. However, I can't think of any other explanation - can you?

 

[GeorgeCooke]

A few weeks ago I would have agreed. However, I can't think of any other explanation - can you?

Possibly cheap nasty lamps or a batch fault.

 

[DPG]

LEDs don't have a high inrush current.
.

Yes they do. It is because of the integral electronic drivers used to convert mains AC voltage to a suitable DC for the LEDs themselves.

 

[HandySparks]

LEDs don't have a high inrush current.

I've always understood that they do.

Yes they do. It is because of the integral electronic drivers used to convert mains AC voltage to a suitable DC for the LEDs themselves.

Depends entirely on the design of the driver. I've measured LED drivers with both outrageously high and pretty low surge currents. If you have a current clamp meter with a peak hold facility, you can test for yourself. Of course, the line impedance of the supply will have an effect on the measured values. The bad ones were, in effect, close to a dead short across the supply (for a limited period).