External security light has failed

[Clive]

Hi,

I had a 150W external, motion-sensor security light fitted. After a few months the performance became "intermittent" i.e the lamp wouldn't always sense movement - even if I truned the sensitivity up high. Then it worked fine for a month. Now it fails to light at all. The test used to be to swich off the electicity supply then switch on. The lamp would come on for 30 seconds then switch off. That action does not make the lamp light now. I have looked carefully at the bulb filament and it looks fine.

The way the unit is fitted it should, with an hour to get a new unit, take a couple of hours to replace. Once I have the unit off the wall, are there any simple tests that will help me decide if it is or is not not a unit problem? The only test I can think is to remove the unit, switch back on the electricity supply and test the voltage using an AVO meter. Any other suggestions?

Thanks

Clive

[The3rd Earl Of Derby]

£4.99 in Aldi for a new one. ;-)

-- Sir Benjamin Middlethwaite

[meow2222]

just see if powers reaching it. normally no need to remove it to do that.

Usual disclaimers and cautions about live risks apply, dont do if you dont know how safely etc. You never know, one of these days it may be Frank Spencer posting here.

NT

[marble]

Just replace it and keep the old bulb.

[Harry Bloomfield]

Clive explained :

They are so cheap that all it is worth doing is checking the 240v supply is there at the fitting and buying a new one if not.

[FaultyFiesta]

Things I would try:

1) Replace the bulb anyway. 2) If possible, disassemble the circuitry housing and check for water ingress (after isolating the light of course). 3) Can you hear the lamp clicking if you walk into the detection zone during daylight? - some do that.

I'd be interested in whether the £15 lights are more reliable than the £5 ones. For me the inconvenience of climing a ladder and drilling new holes in the wall (why does every light have difference hole spacing?) makes it worth spending more if the light is likely to last longer.

[dave]

How much is a new bulb compared with a completely new fitting?

Regarding different hole centres. What I have done is to fit a baseboard to the wall and screw the fitting to that. Diff. centres are then no problem.

[meow2222]

Who knows - I suspect there's little or no correlation though. When you look at what determines sale price in todays capitalism. The traditional price proportional to quality thing seems to be breaking down more often nowadays as other factors loom larger in the equation.

NT

[Broadback]

Others here have the right idea. I spent about 4 hours trying to remove the front plate of one just to replace the bulb, big mistake, in the end I admitted defeat and purchased a replacement. At little over £4 that was the biggest waste of 4 hours I can remember!

[mark_yh]

It would be a pity if there's no option to buy a "decent quality" version of these PIRs though. Most seem to be designed to last a few months, and as other posters have noted, the hours spent getting ladders out in nasty weather fixing or replacing these things is a lot more valuable than saving a tenner on the cost of the original unit.