CFL voltage rating

[Adrian Godwin]

What are the factors affecting the voiltage rating of a CFL or other electronically-ballasted lamp ?

For some time, I've been trying to find a 110V circline lamp & holder for a particular fitting. I'm in the UK, and even 240V circlines aren't very common. The equipment has a 240-110V transformer that I didn't want to rewire.

Eventually, I decided to try a 240V CFL - and it strikes and runs perfectly (not sure whether it's running dimly or not, but it's bright enough for the application).

Is this OK, or likely to be overstressing the ballast, by taking more current for a given power than the 240V circuit would normally need ?

-adrian

[Andrew Gabriel]

Have you checked the ballast rating? I bought some electronic ballasts for a kitchen lighting project a while back. Some of them were rated something like 95-277V input.

If you are underrunning the tube and the ballast wasn't designed to do this, you will shorten the tube life. It's difficult to predict how a ballast will behave when operating outside its design rating.

[Adrian Godwin]

It's a Philex spiral "Eco" CF lamp with an integrated ballast, rated at 18W, 220-240V. I don't much care if the tube life is reduced, but I'm not sure what the ballast consists of and if it's running twice the current to provide 18W at 110V I guess something might get hot.

-adrian

[Eeyore]

The only practical solution I can think of is to break one open, discover the components used and 'reverse engineer' it. The main difference is that the 'HT' is going to be running at half the intended voltage. Better than the other way round at least !

Graham