Running 240V Transformer at 120V

Unless the transformer has a split primary specifically for the purpose of running at either 120 or 240 V you would have to rewind the transformer. This is a fun and challenging task, but you'll spend less time if you flip burgers until you've earned enough to buy a new lamp at Home Depot.

--
-------------------------------------------
Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Ah. Mine is a Nemo Italiana Luce, so I am in the same situation. I was thinking of replacing the transformer that is internal to the lamp, but no luck yet finding one that has the same taps and the same dimensions. Probably I am best off with a 240->120V transformer on the power line. (I assume that I need something rated at 50W or more... right?)

If you can make it impossible for anyone to touch any part of the lamp, there's a possibility that you could run it right off the 240V in the normal household supply, like your dryer or stove.

But you have to be _absolutely sure_ that no part of the mains can EVER touch any part of the lamp that's accessible to human contact. It's also probably a violation of code and who knows how many safety regulations, but if you can _guarantee_ that it's 100% isolated, and double- or triple-insulated, just run it off a 240V outlet.

Probably cheaper and less trouble to get a new lamp, but I've seen people do stupider things.

All of the usual disclaimers apply here, don't try this at home, I take no responsibility for any injury, dismemberment, or death, and so on; I don't even recommend it.

Officially. (wink, wink, nudge, nudge) ;-)

Cheers! Rich

Hello Monty,

Short answer: Probably yes. No. Transformer.

I brought a couple of Artemide Tizio lamps from Europe that are excellent for viewing large schematic plots. The big one contains a 55W automotive halogen bulb. Could have bought new ones here but they are very expensive (no, Tim, can't buy these at Home Depot).

So I rigged up a transformer to feed them 230V.

Regards, Joerg

Ah ! The joys of transformer winding. :-)

I seem to doing it regularly these days.

Graham

Hello Monty,

Depends on the bulb. If it is a 55W like mine I'd go for a transformer of 100W or more. I needed >1000W because some other stuff is hanging on it as well. To save weight and space I built a few that took in 125V which is our local line voltage and put out 100V (Japanese line voltage). Then I connected the secondary in series with mains and got

225V, just about right for gear from the European mainland. You need two fuses if you do that.

Be careful with a straight 1:2 step-up. In many places in the US the line voltage is between 125V and 130V. 260V would be a real stretch for some European stuff. That can turn capacitors into spacecraft.

Regards, Joerg

Hello Rich,

That is usually a prerequisite in Europe. For example, if the lamp is sold in Germany their 230V power plugs are not polarized. Neither is there a clear scheme of which side is hot and which is neutral in a power outlet. Found that out the hard way as a kid (bzzzt...zing).

Regards, Joerg