gu10 leds

[snoged]

can anyone help
i have replaced 5 standard gu10 bulbs with some new gu10 led bulbs.
all is ok when switched on but when switched of some of the leds glow.
these bulbs are the cluster leds 21 per bulb and only a few of the cluster are glowing.
thanks

 

[Taylortwocities]

Dont have too much experience with LEDs but a similar problem can be seen with some low energy lamps.

Usually caused by inductance - possible problems from adjacent circuits or the circuit itself not haveing an earthed cpc. Apparantly an earthed cpc can reduce this effect.

 

[snoged]

thanks for the reply,not an expert with electrics,what is an earth cpc ?
thanks

 

[Taylortwocities]

As these are main-powered lights, there will be a cable carrying the mains power from light to light.

There should be three conductors
Live (brown)
Neutral (blue)
and a third conductor which will be either green&yellow if you are using flexible cable or it may be a bare unsleeved conductor.
This third conductor should be earthed at the start of the circuit and the earth should be carried through each light fitting right up to the last fitting.

Most downlight fittings dont have an earth connection but its important to connect the earths at each fitting so it runs right thru to the end. Check yours is there and is properly connected.

This conductor is called the Circuit Protective Conductor (cpc). Its job is to provide a fault path to earth in the event of dmage to the cable. It also could help your little problem.

To prove this problem is inductance, Take out one of the LED lamps that isnt glowing and put back one of the old GU10 halogen lamps - I'll bet your problem goes away - that's cos the halogen lamps dont have any fancy electronics that get confused by stray voltages. Even a few volts can make a LED glow.

 

[snoged]

many thanks for your advice ill try that tomorrow
kind regards