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high ac voltage destrucive or not?

After reading all the threads about ac voltage these past few months I pulled out my handy dandy fluke meter and meaured about 126 volts ac out of the wall and 128 out of my powervar. For all the electical gurus is this harmful to the electonics or part of the variables in ac delivery , thanks for any help. system consist of pass 350, sfl2 preamp and audiologic dac.
renotunes
gs5556
1,233 posts
 
If you're in the US, then the utility voltage will vary anywhere between 114 and 126 Volts - which is normal and the allowable US standard. Appliances with UL listings will operate between 110 and 127 volts with no damage. Also, utility voltage is RMS, meaning it's an average of sorts. The actual voltage at your outlets can be much higher - the peak to peak voltage can reach 170 volts. Your fluke meter is most likely not a true RMS meter and therefore not giving you an accurate measurment with respect to the average or RMS reading. You can call the utility and tell them you suspect high voltage and are concerned and let them make the call. If it was my house, I wouldn't worry.
sean
6,231 posts
 
You're right on the edge of being high enough to cause damage to some gear. Much of this will depend on the individual component and how it is designed.

Keep an eye on the voltage for a few days and chart the voltages and the day / time that you take those readings. If this is a regular occurance or only occurs at certain times, , being able to provide the power provider with specifics may help them to rectify the situation. Sean
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aball
2,016 posts
 
In circuit design, a 50% voltage rating increase is typical so there is no problem with 128V. If your components get damaged by it, you know never to buy from those companies again.

Also, upper-level Fluke meters ARE true RMS (beyond model number 77 (or new 177) I think).
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