Electronics > Projects, Designs, and Technical Stuff

copper "belt" around transformers

(1/3) > >>

I have noticed that on many power supply transformers, there is a copper "belt" that encircles the entire unit for magnetic shielding. If that's not required, will removing it significantly increase the efficiency?

Google is your friend......


The professional audiophile (no not audiofool this time) community know much about transformer eminations and the effect of copper and Mu metal screens. This is one area where appliance poor design can create havoc with mains hum on an amplifier output.

I would always leave the copper screen in place.

I'm going to be using it (actually an inductor) in a power inverter, so I plan to remove the "belt" if it would significantly increase efficiency, especially at low load. I will leave it if the gain would be insignificant.


If the copper actually absorbed useful energy from the transformer/inductor it would be a very bad idea because it infers that it is acting as a shorted turn on the core.....not a great idea in any transformer/inductor design.

From what I understand, the copper 'belt' isn't a shorted turn around the cores operational (useful) magnetic flux, and is purely a containment method for spurious E, and to some extent, H field emanations from the core & windings. I don't see how your efficiency will be adversely effected by a correctly installed and implemented copper belt. You could end up with an increased chance of an RFI problem without it though.

>>> so I plan to remove the "belt" if it would significantly increase efficiency

The few transformers I have used that have this belt seem to work as designed. The power transformer in my TEK 455A2B2 has just such a belt, and it, too, works just fine.

I cannot see how removing it would increase efficiency in any way. It is probably (in my cases) there for shielding.

... C


[0] Message Index

[#] Next page

There was an error while thanking
Go to full version