Monitor Iso. transformer question

mike200mph

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Trying to Bring a Carnival back to factory life again, When I measure the a/c voltage coming out of my house outlet and I have 124.5. when I measure it coming out of the big black(Sega/Gremlin) transformer that goes to the monitor it's 131-131.5.My question is, Is the iso.transformer bad?Am I going to burn up the monitor chassis with the voltage being that high? should I change the Isolation transformer.I have not installed a monitor yet and I was thinking about useing a g07 monitor.
Any help would be appreciated.

Thanks Mike
 
You are measuring the transformer output without it being under a load. You will always read higher voltage when there's no load connected to the transformer.
 
Probably ok.

Remember, to accurately measure AC volts, you need a "true RMS" style meter.

Interesting. So my el-cheapo DMM is probably not going to accurately read AC voltage. How much would you expect it to be off? Substantially? 10%?

edit: My DMM instructions say "response: average responding, calibrated in RMS of a sine wave". I assume this doesn't qualify as a "true RMS" style meter?
 
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Also, a low battery can cause your readings to be off by up to 15 volts...
 
A true RMS reading meter will state so in it's owner's manual and usually on the meter itself. Plus the fact that true RMS meters cost more than regular meters.
 
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