William,
That's about all you can do besides measuring the internal coil twmperature
which is read in the center of each winding. Then make sure that temp is at
least 2X less than the wires maximum rating. In engineering, a factor of 2 is
at least used on anything as compared to its maximum. The core can be large
enough, but the wire not be big enough or wound for say ICAS instead of CCS.
That's a difference of 750-800 cir. mils per ampere compared to 1000-1200 cir.
mils per ampere. Some of the cheap ones uses 500 cir. mils per ampere and run
extremely hot but are not made to run or last that long. The efficiency can
generally be figured around 85-90% for most HV plate transformers. There the
I^2 X R losses and the iron losses combined.
Best,
Will
----- Original Message -----
From: "Dr. William J. Schmidt, II" <bill@wjschmidt.com>
To: kenw2dtc <kenw2dtc@comcast.net>, amps@contesting.com
Subject: Re: [Amps] questions on my tranformer test
Date: Sun, 12 Jun 2005 14:11:50 -0500
>
> I would think that the best way to tell is measure the wire size of the
> secondary winding. The second best way is measure he cross-sectional area
> of the transformer, as theoretically it is related to the power capabilities
> of the steel.... which you can back into current (after accounting for
> reasonable efficiencies). 180F seems a little warm for a CCS transformer...
> maybe Will can weigh in here...
>
> Sincerely,
>
> Dr. William J. Schmidt, II K9HZ
> Trustee of the North American QRO - Central Division Club - K9ZC
>
> Email: bill@wjschmidt.com
> WebPage: www.wjschmidt.com
>
> "If computers get too powerful, we can organize them into a committee; that
> will do them in." -- Bradley's Bromide
>
>
> ----- Original Message -----
> From: "kenw2dtc" <kenw2dtc@comcast.net>
> To: <amps@contesting.com>
> Sent: Sunday, June 12, 2005 1:39 PM
> Subject: [Amps] questions on my tranformer test
>
>
> > Hi,
> > I'm trying to figure out the current rating of a plate transformer. This is
> > my test setup:
> >
> > http://w2dtc.com/2005-0610-transformer-test-page.htm
> >
> > Questions:
> > 1. Is this a valid way to find the secondary current capability?
> > 2. Is the internal temperature of 180 degrees F too high for a transformer
> > under load for 5 hours?
> > 3. Is there a problem running this center tapped beast in a full wave
> > capacitive input configuration?
> >
> > Thanks and 73,
> > Ken W2DTC
> >
> >
> >
> >
> > _______________________________________________
> > Amps mailing list
> > Amps@contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
> >
>
> _______________________________________________
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> Amps@contesting.com
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