How much can a monitor take??

djw90

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My pacman cocktail isolation transformer meters 135v at the monitor plug. Is this to much? Im reparing the monitor and need to know if I shoud buy a new isolation transformer. Would like to keep it original if I can.
 
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Monitor load won't affect the AC from the isolation transformer.

What are you reading on the other side? Same thing? What about from the wall outlet? Same thing? Then check the batteries in your meter...
 
Monitor load won't affect the AC from the isolation transformer.

What are you reading on the other side? Same thing? What about from the wall outlet? Same thing? Then check the batteries in your meter...


I will look at those other readings tonight. I think im prob due for new batteries in my meter too.
 
To get an accurate voltage reading of AC power, you need a meter that is equipped for "True RMS" reading.

A transformer will always read higher without a load connected.
 
I'll also add......135 volts doesn't seem like a big deal to me.

Remember when the US standard was 110 volts. Now we're at 120 volts.....hell, the wall plugs of my shop output 138 volts.

I have no idea why our standard operating voltage in the US keeps slowly rising......and I do believe at some point.....it's gonna be a problem for older equipment. I just don't think we're there.....yet.

Edward
 
I can say that it CAN cause a problem depending on which monitor you are using. Both Dokert and I have had issues with a transformer with 120 in and 132 out and it was blowing the monitor. The Monitors had a 123 or 130v regulator, and the 132 was too much for it...
 
all depends on the monitor model.
some will have a lower acceptance threshold.
some will accept 90-240 volts ac without the need to change anything on the board and run exactly the same.
a good meter would also be needed to get true rms reading.
 
I can say that it CAN cause a problem depending on which monitor you are using. Both Dokert and I have had issues with a transformer with 120 in and 132 out and it was blowing the monitor. The Monitors had a 123 or 130v regulator, and the 132 was too much for it...

Curious.....were these Wells-Gardner monitors?....with the STR series of regulators?....and was it killing the regulator or something else?

Edward
 
Remember when the US standard was 110 volts. Now we're at 120 volts...

That's a perception thing. 110, 115, and 120V AC all refer to the same thing, one a leg off a 220/240V two phase circuit.

As for you local voltage being higher, that varies by the stepdown transformer, line load, and ultimately distance from the head end of the transmission and distribution lines.
 

That's an interesting read, but I still dont understand how all that damage was happening unless the transformer was no longer isolating (or something going on I don't fully understand). All of those Wells-Gardner STR series regulators are rated at 200 volts maximum input......The 123V or 130V is the regulated output. I just don't see how 134 volts could damage those regulators.

I also see (and don't understand) the same thing Riptor mentioned in your old thread.....All new isolation transformers I buy generally output 132-136 volts.......even with the input dialed down to 120V exact.

Edward
 
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