LED light flashing?

[BigSim]

Hi guys.

Came accross this issue and wondered if anybody else has experienced anything similar. Installed a new lighting circuit in some outbuildings and the customer supplied a little 10w LED flood light for one of them. Completed the installation and when the testing was complete energised the circuit. Turned the light switch on and the LED light came on (so far so good), but when I turned the switch off, the light started pulsing once every 3 seconds?

The light switch was IP rated with a location neon that would illuminate when the switch was off. The only thing that I could think off was that this was allowing enough current to flow to the LED driver (through the lit neon), but not enough to 'strike'. I've also had the same effect when a customer installed a replacement LED lamp, where the same switch was installed.

Installed a 30w LED flood light in another building, and it works fine (including turning off!). There were no other loads connected at the time just a bog-standard radial lighting circuit wired in SWA and surface clipped. It just seems to happen with low wattage LED lights/lamps.

 

[Nuvo]

did you undertake an insulation resistance test while the light was connected?

 

[BigSim]

No, all loads were disconnected to prevent damage to any sensitive electronics.

 

[davesparks]

Is the indicator lamp wired in parallel with the switch or from s/l toneutral?

 

[BigSim]

The neon is in parallel to the switch (no neutral).

 

[davesparks]

Then it's probably the current through the neon charging the capacitors in the LED driver

 

[BigSim]

Then it's probably the current through the neon charging the capacitors in the LED driver

I was thinking the same. But when I spoke to a work colleague all I got was a blank face! I'm glad somebody else has come to the same conclusion!

 

[davesparks]

I was thinking the same. But when I spoke to a work colleague all I got was a blank face! I'm glad somebody else has come to the same conclusion!

Drawing the same conclusion? Nah, more like stating the bleeding obvious!
Just chop the neon out or fit a dummy resistive load to dump the current somewhere.

 

[BigSim]

So has anybody else had the same issue?

 

[davesparks]

I should think every electrician has encountered a variant of this problem these days, it's a common issue with LED and low energy lighting.

 

[BigSim]

Didn't have this problem with a good old fashioned 500w halogen flood light! LED are still a new thing for us down here!

 

[Jimmyb]

it is the neon I had to remove the neon or run a neutral to the switch and connect the neon to that. come back halogen lol