How to fix flickering new lightbulbs?

hanspet

Hi,

I needed to replace the lightbulbs in our living room and I bough some LED ones (picture of green box 11W), but after installing them they were flicking constantly. I went back to bunnings and they told me that this was because the voltage (or something like that) was too high on those lightbulb,and that I should buy ones with lower voltage, becuae I risked damaging the electrical system (or something along those lines), so I bought another four light bulbs (picture of purple box, 6w). The setting is like on the third picture. Its an old house and I suppose this is an old electrical system? I dont know. But, when I installed this new lighbulbs from the purple box, they were still flickering a bit. Now they have stopped flickering, but each time I turn them on they do this weird thing: they sort of hesitate to turn on for a few second and then they turn on. This whole thing has now cost over $70, which is not OK.

Anyway, I just want to know if it is safe to have these light bulbs as they are now. They seem fine, not flickering, the only issue is how weirdly they turn on.

MitchellMc

Hi @hanspet,

Is this a simple on/off switch or is there a dimmer?

It sounds very much like you’ve got an older leading-edge dimmer in that circuit, which were commonly installed in older homes and are designed for incandescent bulbs, 240V linear halogen, 240V GU10 halogen, and even wire-wound low-voltage transformers. Those dimmers rely on a higher electrical load to operate properly, whereas modern LED bulbs draw very little power and use internal electronics that don’t play nicely with that style of dimming. That mismatch typically causes exactly what you experienced, including initial flickering, then partial improvement with different bulbs, and now that slight hesitation or delay before the lights turn on.

The explanation you were given about “voltage being too high” isn’t really accurate, as standard mains voltage in Australia is already around 230–240V and both sets of bulbs you bought are designed for that. The issue is how the dimmer is controlling the power, not the supply itself. Dropping from 11W to 6W doesn’t fix it either and can sometimes make it worse because it reduces the load even further. To test this, you can pop the globe is any other fitting that just has an on/off switch. I'm fairly confident you'll find the globes work fine with the power in your home.

If you want to use LED globes, you’ll need to have an electrician replace the dimmer with a modern trailing-edge dimmer that’s designed for LED loads, or remove the dimmer altogether and use a standard on/off switch. Otherwise, you may continue to get that slightly odd startup behaviour even if the flickering has stopped. Unfortunately, as I am not an electrician, I'm unable to qualify whether the current setup is safe. It would be my advice to consult one, and if you do have a dimmer which is not suitable for these LED globes, to either have them replace the dimmer, or switch back to incandescent or halogen globes.

I do apologise for this inconvenience. For the globes you haven't used, I'd just pop them back in the packaging and return them at the store.

Please let me know if you have any questions.

Mitchell