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From: miker@polari.UUCP (Mike Ranta)
Newsgroups: sci.electronics
Subject: Re: ? Regulation of transformer
Keywords: power supply, transformer
Message-ID: <3896@polari.UUCP>
Date: 29 Apr 91 00:38:01 GMT
References: <1991Apr26.050204.7569@vlsisj.uucp> <1991Apr27.135045.29595@eng.umd.edu>
Organization: Seattle Online Public Unix (206) 328-4944
Lines: 13

>I am confused with the definition of regulation of transformers.
>Say a transformer with 110 volts at primary and 24 volts(rms) at
>secondary with 10% regulation and 1 Amp(rms) at secondary.
>What is the correct explaination of this 24 volts(rms)? is this under
>0 amp cureent or under full load current(1 amp)?

The rated voltage is nearly always given at the rated current.  The
regulation figure indicates that for every 100% increase in load
current there will be a 10% decrease in output voltage (within the
maximum ratings of course).  In other words, if we were to load
your particular transformer at 0.5 amps, one would expect a 5%
increase in voltage to 25.2 volts rms.  This doesn't quite hold
true in the limiting case of no load, but it's close.