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From: jj@alice.UUCP
Newsgroups: rec.audio,sci.electronics
Subject: Re: Audio equipment on 220V/50Hz
Message-ID: <7465@alice.UUCP>
Date: Thu, 19-Nov-87 13:08:54 EST
Article-I.D.: alice.7465
Posted: Thu Nov 19 13:08:54 1987
Date-Received: Sat, 21-Nov-87 19:20:35 EST
References: <4032@watdcsu.waterloo.edu> 8884@utzoo.UUCP <63KEN@ORION>
Organization: AT*T-BL, Murray Hill, Signal Processing Research Department
Lines: 26
Xref: utgpu rec.audio:3629 sci.electronics:1546
Summary: Oh, wrong, just WRONG!  60 vs. 50 Hz.

In article <63KEN@ORION>, ken@orion.bitnet.UUCP writes:
> Using a 60 Hz transformer at 50 Hz will probably be ok, the opposite might
> not.  Heat generated by the transformer is a function of the 'area' of
> the hysterious curve multiplied by the frequency.

Plus, the heat generated by resistive losses in the windings, which
could be remarkably severe if the transformer, designed for 60Hz,
just happens to saturate at 50Hz.  The resulting inrush, which would
certainly nuke fuses at least, might also create some spikes that
would cause trouble downstream of the transformer.


The eddy current losses go up with frequency, yes, but the maximum
voltage-time integral goes up with decreasing frequency, and
is what determines the saturability of the transformer.

Even if it doesn't saturate, you can get out far enough on the BH
curve to cause more losses and funny waveshapes/etc in the secondary
that can cause lots of excess heat.


-- 
OPUS FOR PRESIDENT IN '88, TEDDY BEARS SUPPORT THE MEADOW PARTY!
"...Kulimani, Kulimani sizwe! ..."
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