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140 Volts AC out of your wall? That's really not good. I can't imagine your electrical appliances are happy with that. Even 130 Volts is out of spec. NEMA spec is +/- 10%, which is typically listed as 103.5-126.5 Volts

 

Wow, 140V off the wall? Is this regional thing? Are sensitive electronics rated for 110V works OK on 140V outlet without a step-down transformer?

 

Senior moment. My L2 is actually 240-248 most of the time. I think that's where I got the "40." My multimeter just decided to go on the fritz and not switch from DC to AC, so I can't check it now. But the L2 meter I've installed is reading 247 at the moment, so I'd assume, if the two sides of the panel are even that right now it's about 123-124 volts. I have seen 130 before.

 

That I can believe. BTW, are household wall outlet ever 110V? I have seen 110/220V on electrical specs, but most of the houses I have lived had 120V/240V. Are they two different standards in the US?

 

How so?

 

Decades ago, it was 110V, but has increased. I don't know when that happened. 120 is nominal, but it can vary. It's not by location, but it's by the load on the grid and how well the automatic tap on the utility's transformers adjust to keep the voltage in spec. For example, I got a late-night call from work back when I was supervising electricians that our voltage had climbed from 480 to WAY over 500V. I seem to recall seeing a 560 when I went in to check on it. They were blowing fuses all over the place! They had called the power company and the response, of course, was that all was well on their end. Well, we were such a big customer that they had assigned someone to be sort of a representative for us. I called him, he checked on it, and it went back to normal within an hour. Next morning, he called and told me they found that one of those taps was stuck. So, as people went to bed and the power load dropped, the voltage increased. A bunch!

 

Did you mean 4 kVA? They're usually measured in volt/amps. We blew one at our plant in Ohio that was 2,000 kVA. I was standing next to it at the time. Biggest boom I ever heard!!

 

Back to the DST issue, as I understand it, the NAV system in the car is using GPS (from satellites) and watches are using WWV, which is shortwave radio (5Mhz, 10MHz, 15Mhz, among other frequencies). GPS has no notion of time zone or DST; its all UTC, from the satellites. The problem with DST is when the rules about when DST is in effect change, not whether a particular area honors DST. On most DST-knowledgeable devices, just as one sets the time zone manually, one can manually set if your area honors DST. This deals with particular states not honoring DST (like Arizona) or DST not being honored in particular locations (like some Native American reservations). I think that what is currently under consideration is whether an entire state honors DST, where a fixed setting saying that DST is honored or not would suffice, not changing the formula for when DST is in effect.