Originally Posted By: Kruse
Originally Posted By: SecondMonkey
But when I tested my regular "110 volt" outlets, they read 138 volts! I know 110 isn't supposed to be an exact number, but 138 seems awful high!
The electric companies have slowly raised the voltage over the years to help stop the loss of electricity between the power station and your plug in outlets. The higher the voltage, the less loss they have.
Older appliances, such as tube audio amps, have a hard time with the increased voltages.
Typical household voltages now run from about 118 to 125, but can vary all over the place. If your measurement is indeed accurate at 138, it is too high.
Call your power company and have it measured and adjusted.
+1
Cut all breakers off to the building as to insure 0 current flow and measure the voltage at the main breaker. This voltage will be very close to the output of the transformer. report this number to the power company if it is above 125 VAC. As some of the reports stated above, sometimes higher voltage is better becuase it reduces the current draw to get the same power, but running devices that were designed to run a particular voltage, on higher voltages will reduce life or blow them up. 138V is to high, get it fixed. Make sure your meter is reading VAC RMS. I dont think this is a major issue with most meters but there is a differance between RMS and Peak to Peak. Just make sure your meter is measuring true RMS and not some funky reading.