VLV (Very Low Voltage)

[n2ize]

I notice I am getting very low voltage into my house tonight. Incoming utility voltage is between 100-102 VAC... the lowest its been since my power was restored. I assume it has to do with the recent catastrophic events. But if it continues I might have to have Con edison check my local connection.

[N2CHX]

Fortunately, most modern electronics are designed to run on anything between 90-250 volts.

[XE1/N5AL]

I can spare a few volts for you, John.

Here, I have the opposite problem: the voltage is too high. Power to the house is three-phase 220Vac, rather than the 208 Vac which is common for three phase systems in the U.S. As a result, Each of the three lines to neutral have a nominal 127 Vac potential (usually runs at 130Vac), rather than the 120 Vac common in the U.S. Light bulbs just don't seem to last as long!

[n2ize]

Prior to the storm my AC voltage was almost always running a bit on the high side (around 125 - 126 VAC). Since the storm its been fluctuating between 100 VAC to 116 VAC. Seems like it always tends to dip to the low side in the evening hours. I have noticed that the batteries on my UPS power supplies very slowly start to drain when the voltage goes way down. It could perhaps have something to do with the power supply trying to compensate for the low input voltage but then again, a decent UPS should be able to compensate without using any battery. A multi tap autotransformer in the output side of the power supply should be able to provide adequate compensation for low or high input voltage without having to touch the battery. . Matter of fact I believe that is how many of them do compensate for low/high voltages.Perhaps the cheaper UPS's do it differently or, perhaps it is just the charging circuit or some other anomaly. In any event it is a hands on learning experience for me.