Unknown Micro Switch Transformer any use in tube amps?

[molomo74]

Hello,

i recently got a "unknown" transformer out of an old automotive exhaust measuring device.
Unfortunately i can't find any information about that transformer online and my knowledge of transformers in general is pretty limited.

Maybe anyone of you knows that type of transformer. It it any good in using in a tube amp related build? May it only be useful as a choke or maybe as a 5V rectifier filament supply?
I really don't know the application this was used in the former measuring device, but i guess it in a kind of relay circuit for the many pilot lights.

It has 3 pairs of wires coming out which show continuity.

I am based in europe, so i would run the transformer at 230VAC.

Kind regards,
Mo

 

[Pete Farrington]

I am based in europe, so i would run the transformer at 230VAC.

It’s noted as being intended for 115V, so I think it’s of no use to you.

 

[radiocaster]

If you hook it up to 230V, you;ll get 12V on the other end, which can be used for heaters on 12A*7.

Not sure what the other pair of wires gives, maybe also 12V, maybe something else. Doesn't say, but someone else might know about these.

 

[Pete Farrington]

If you hook it up to 230V

As a general principle, my understanding is that’s a bad idea, primary inductance may be be too low, the magnetising excitation current may be far higher than the designer intended, and the core may saturate at low loads, causing primary inductance to collapse (and it’s only 15VA to start with).
So this idea seems it may be a potential fire hazard.
Have you tried it?

 

[molomo74]

Thank you for the quick replies!

I did not try to hook it up to 230 yet, and i am afraid after your remarks Pete.
Do you know if that kind of transformer could be useful as a choke and how to determine the inductance, max amperage and DCR?

 

[Pete Farrington]

I did not try to hook it up to 230 yet, and i am afraid after your remarks Pete.

If you try it, use a light bulb limiter.

Do you know if that kind of transformer could be useful as a choke

I don’t think it could cope with much DC before the core saturates, as it’s designed for AC. When the core saturates, the inductance collapses.