Flicking CFL bulb / fitting even after replacement

Forums › Home Workshop DIY › Flicking CFL bulb / fitting even after replacement

1 | 2

sparkz25

535 posts

Ultimate Geek

#1744659 20-Mar-2017 17:41

how old is the house? is it a 2 way switched circuit? is it livened at the lights? it will be inductance in the circuit if its 2 way or livened at the lights been through this process with a client many years ago and i couldn't find anything wrong until i hooked a meter up and watched the voltage increase and then drop off as the cfl ignited, the only way around it was a to put a incandescent lamp in to stop it,

i found that with the inductance within the 2 way circuit it was enough voltage to slowly charge a set of filtering caps within the cfl lamp itself and then when the voltage reached about 50-60v it would discharge and give the flicker of the lamp

timmmay

15907 posts

Uber Geek

Trusted

Subscriber

#1744736 20-Mar-2017 19:13

House is very old, but those lights were installed a few years ago so that part is new. I don't know the answer to any of your other questions @sparkz25 but thanks for asking.

There are two fittings on that switch, and two fittings on another switch on the same plate. Since only one fitting is flickering I guess it has to be the fitting. I chucked the first bulb out because I figured it was spent, but the second I have. I'll try a known good bulb in there just to prove it.

My neighbour's an electrician who put it in, well one of his guys did. I guess I should get them back out to check it.

Thanks all :)

andrewNZ

2200 posts

Uber Geek

#1744746 20-Mar-2017 19:33

Are you saying it's flickering when it's off or when it's on?

The question about 2 way switching is asking if there's more than one switch for the light.

Location: Dunedin

timmmay

15907 posts

Uber Geek

Trusted

Subscriber

#1744750 20-Mar-2017 19:46

Thanks Andrew. It's flickering when it's turned on, when it's off it's off. The light only has one switch, but the switch controls two fittings. Only this fitting flickers.

timmmay

15907 posts

Uber Geek

Trusted

Subscriber

#1752681 1-Apr-2017 14:50

I swapped the bulbs between fittings, the flickering stopped. My electrician was over, I mentioned it to him. He said sometimes the sockets expand when they get hot, screwing them in firmly can help, or finding the bulb that's the right size to make good contact.

Fortunately I didn't have to do anything. I'll get some LEDs at some point, but since they're rarely used it doesn't much matter.

Thanks for all the advice offered :)

tchart

1599 posts

Uber Geek

Trusted

Subscriber

#1752712 1-Apr-2017 15:39

@timmmay our previous house (80s Lockwood) did this in one room. Only did it with CFL bulbs. When I looked into it I came to the conclusion that the wiring was the problem and there was some current leakage (the CFL was storing and releasing every couple of seconds). Can't recall where I found that info but I think the issue is the switch had positive/negative switched or something like that.

tchart

1599 posts

Uber Geek

Trusted

Subscriber

#1752713 1-Apr-2017 15:41

Oh sorry just saw your is flickering when on. Mine did it when off.

sir1963

1167 posts

Uber Geek

Subscriber

#1753051 2-Apr-2017 09:30

timmmay:

I have two sets of two light fittings in my lounge, standard not downlight. One is used regularly, the ones over the TV only occasionally. They have GE tiny spiral warm white bulbs in them - these are CFL bulbs.

We've started using the TV set recently, I noticed one bulb was flicking. No problem, I changed it, with a replacement bulb purchased at the same time as the original. The new one flickers too. It's not a really huge flicker, it's subtle enough that some might not notice it, or might notice the light wasn't quite right but couldn't work out why.

Is it just bad luck? Could it be a bad fitting or bad circuit? Should I just put an LED bulb in to see what happens?

If LED is a good idea, any suggestion for brand / model / vendor? They're still not that cheap, but much better than they used to be.

Ok, CFLs etc have power factor correction caps in them.

ALL power cables have leakage, both resistive (Extremely small in good cable) and capacitive where by some when the light switch is off, the wire going to the lamp can get an induced voltage on it. This will put a charge on the Capacitor.

When this capacitor has sufficient charge on it, it will cause the start circuit to fire and the lamp Flashes.

These behaviour is most common on circuits with only one lamp on the circuit.

I have one which flashes with an LED lamp but not a CFL and another that flashes with a low wattage CFL but not a high wattage CFL.

OR, if the lamp is not used very often, just put a standard lamp back in its place, the power saving you going to make using an LED/CFL will be so close to none it won't matter.

timmmay

15907 posts

Uber Geek

Trusted

Subscriber

#1753080 2-Apr-2017 09:47

sir1963:

Ok, CFLs etc have power factor correction caps in them.

ALL power cables have leakage, both resistive (Extremely small in good cable) and capacitive where by some when the light switch is off, the wire going to the lamp can get an induced voltage on it. This will put a charge on the Capacitor.

When this capacitor has sufficient charge on it, it will cause the start circuit to fire and the lamp Flashes.

These behaviour is most common on circuits with only one lamp on the circuit.

I have one which flashes with an LED lamp but not a CFL and another that flashes with a low wattage CFL but not a high wattage CFL.

OR, if the lamp is not used very often, just put a standard lamp back in its place, the power saving you going to make using an LED/CFL will be so close to none it won't matter.

I think you described the situation where the light flickers when it's turned off. My problem was when it was on. It's solved now, thanks.

1 | 2