LED Floodlight with Time Lag Switch - LED Keeps Flashing

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It might be that the timer when OFF "lets through" a lot more current than is norma for similar timers and controllersl. The fact that the web site mentions a 4 uF power factor correction capacitor is a big hint that the let through current has to be high. The flash rate of what is quite a large LED supports the theory the let through is high.

The is a let through current as there has to be some current through the timer when OFF in order to power the timer's electronics.

If capacitors cannot solve the problem and the timer is not defective then it maybe necessary to use relay to provide a clean break switch for the LED but the relay coil may not allow the necessary let through to power the timer.

When I search for a 4uF capacitor they all seem to be "motor run capacitors". Will this work?

My local Maplin has a 3uF Motor Run Capacitor http://www.maplin.co.uk/motor-run-capacitors-440v-30309 or a 4.7uF "Audio Grade" capacitor http://www.maplin.co.uk/audio-grade-polypropylene-axial-capacitors-393 Will either of these work? or am I now thinking way too far outside the box. LoL.
 
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So my LED light is now working off the timer properly. No flashing in sight! All thanks to this £2.80 eBay bargain that arrived today, sooner than expected.

207000_206763_64793_84262411_thumb.jpg


In a strange twist of irony it was originally installed in a fluorescent light fitting and was REMOVED from said brand new fitting to allow for conversion to LED?!

I was just about to give up my search for the correct capacitor when I stumbled across this 5uf one and thought it was worth a punt for less than £3.

So thank you to everyone who provided their opinion and expertise!
 
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Been asked and answered many times

When the switch is OFF capacitive coupling between Live and Switched Live in the wiring to the switch allows enough energy to reach the lamp and make it flash. A well known problem with energy saving lamps. They save this very small trickle of energy until it is enough to make the lamp flash.

Putting a capacitor across the lamp will absorb this energy and prevent the lamp flashing.

Capacitor 0.047uF micro Farads 250 volts AC in series with a resistor 100 ohms

Which come pre-packaged as a contact suppressor from RS Components

RS Stock No. 206-7847
Manufacturer Evox-Rifa
Manufacturers Part No. PMR209MB5470M100

There are other sources of the contact suppressors
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Read more: http://www.diynot.com/forums/electrics/low-energy-lightbulbs.354983/#2674731#ixzz2b6MVZeeg[/QUOTE]

I have this same problem and have read this post throughout. Can you please specify something about the type of capacitor to be used, polyester, tantalum etc? Or will any capacitor type do? I was thinking of installing it in the motion sensor base with the terminal block leading to the outside led lamp (about one metre away from the motion sensor).

Thanks for any info.
 
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I've just encountered this problem too & fixed it for no cost :)
Inside my PIR switch was a capacitor across one of the the relay contacts that is meant to suppress relay arcing when switching the incandescent load. If converting to led bulb this suppression isn't needed so the capacitor can be removed, or just as easy, just snip the leg. The tiny amount of leakage current through this suppression capacitor is just enough to make the LED flash momentarily as it sits there charging and discharging.
It will normally be sat right next to the relay block inside the PIR switch.

Please note - This solution ISN'T valid if you have a mixture of halogen/incandescent lights being switched by a single PIR switching unit, since you'll still need the arc suppression to ensure the long life of your switching relay, however in a pure LED set-up, the relay is not switching anything near the usual (halogen) current so the capacitor isn't required and can be dispensed with.

Hope this helps someone else who's confused with the 'flashing LED bulb' issue :)
 
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Since you solved your problem by removing a capacitor, and most people need to add one to solve theirs, the chances of you helping people who are confused are much much lower than the chances of confusing people who need help.

Did you actually read the posts in the topic?
 

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