Hello, and a question

Hello all, this is my first post on what looks like an excellent site. I'm starting with a question if that's ok

I've upgraded my old 240v enlarger to one that has a 12v transformer. I use an inline switch (no timer) and need to know whether to place it between the mains socket and the transformer or between the transformer and the enlarger.

To tell you a little about myself; I enjoy film photography, mainly B&W, using my Rolleicord Vb and Zorki 4. I haven't been doing as much photography as I'd like to, but I'll try to remedy that this year.

Thanks in advance,

Alex.

Alex -

Welcome!

I would put the switch between the mains socket and the transformer.

There was another thread a few days ago on the issue of transformer losses. If you place the switch between the transformer and the enlarger, the transformer will be continuously energized, and will incur continuous losses. Over time, these will cost you money. It is also possible that they could result in accelerated failure of the transformer.

Louie

It will work either place, but I would recommend placing it between the mains and the transformer. There are two reasons for this. The most important is that it needs to handle less current in that position. The 12V lamp will draw 10 amps or so, which requires a high current switch. The second reason is that a switch in the mains line disconnects the transformer and its wiring when opened, which, for the usual setup, is marginally safer.

OK, between the mains and the transformer it is. Thanks for quick replies, and for explaining the reasons so clearly.

Alex.