Supply for fluorescent desk lamp

[ban-all-sheds]

Got me an "Anglepoise" type desk light that uses an 11W PL lamp.

It's powered by a wall-wart (never wondered why), and the other day I managed to get the flex caught around my foot as I got up from my desk, and I ripped the thing sideways out of the socket. The earth pin snapped off the w-w and the L pin bent.

Anyway - "NP," I thought, "I'll buy a new supply, wonder what it is". Nothing on it to indicate o/p voltage and anyway, I began to wonder, why would you want an ELV supply for a fluorescent? (It is a regular PL lamp).

So I opened it up, and all that's in there is an isolation transformer.

Any ideas why?

Plan B is to see if I can fit the transformer into a generic empty w-w enclosure, or if not into an ordinary small case with a flying lead, but I'm resenting the hassle - it's an LV light, why can't it just be plugged in?

 

[Click-Sure]

Seems a bit strange and over the top to me BAS.

I take it the metal chassis of the fitting is either earthed or its class 2?

Unless the fitting is class 1 and the joints/springs are not sufficient to transmit the earth connection over?

 

[Spark123]

Is it an isolation transformer or a choke?

 

[hairyben]

It'll be the flourescent control gear/ballast etc inside an oversized plug- this keeps the lamp head slim.

 

[Steve]

I have what sounds like a similar luminaire.

Mine has the choke etc in a little box at the base of the arm, on top of the round peg that fits in the weighted base. The mains cable emerges from the box to a normal mains plug.

 

[ban-all-sheds]

It's not earthed - the flex is 2 core, but you wouldn't earth something that was supplied via an isolation transformer...

But ignore me, and the above

It won't be an isolation transformer, will it - it'll be the ballast.

Oh dear.

But, Scout's Honour, I did realise that myself - I'd only seen Click-Sure's reply when I started typing - it took me a while as I stopped part way through to do some tests to see if the body of the light was isolated, if the "transformer" output was isolated from the input...

I still need to get my coat though.