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Calculating transformer loads #217593
09/09/16 03:38 AM
09/09/16 03:38 AM
sparkyinak  Offline OP
Joined: Jul 2007
Posts: 1,329
Just carious. If I had running data from with the primary or secondary side of a transformer, can the other side be calculated based off of the transformer data plate or perhaps other data?

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Re: Calculating transformer loads [Re: sparkyinak] #217594
09/09/16 09:07 AM
09/09/16 09:07 AM
ampherder  Offline
Joined: Sep 2011
Posts: 20
Volt-amps in = volt-amps out + losses.

Re: Calculating transformer loads [Re: sparkyinak] #217595
09/09/16 01:32 PM
09/09/16 01:32 PM
gfretwell  Offline

Joined: Jul 2004
Posts: 9,185
It is calculating those "losses" that separate electricians from engineers. wink

Greg Fretwell
Re: Calculating transformer loads [Re: gfretwell] #217596
09/09/16 02:44 PM
09/09/16 02:44 PM
twh  Offline
Joined: Mar 2004
Posts: 928
Regina, Sask.
My guess is the losses are I squared x R, calculated for the line side and the load side. I don't think the hum uses much power.

Re: Calculating transformer loads [Re: sparkyinak] #217597
09/09/16 05:52 PM
09/09/16 05:52 PM
wa2ise  Offline
Joined: Nov 2002
Posts: 786
Oradell NJ USA
There's also the losses in the transformer laminations. Better quality steel would have lower losses, but would be more expensive. The transformer would not get as hot while it is powered but unloaded. Probably less hum.

Re: Calculating transformer loads [Re: sparkyinak] #217598
09/09/16 11:01 PM
09/09/16 11:01 PM
gfretwell  Offline

Joined: Jul 2004
Posts: 9,185
If Scott stops by I am sure he can tell us about a whole lot of things that affect "loss" in a transformer. I have bumped around the edges of this stuff but just enough to understand this is more than 2 coils of wire and a core when you get down to the nitty gritty of the difference between the "goesinna" and the "comesoutta". The only thing I know is the loss ends up being mostly heat so the temp this thing runs at is a pretty good clue about the efficiency.

Greg Fretwell


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