rfc@briar.Philips.Com (Robert Casey) (12/05/90)
I've had a little adventure with the powerline voltage at my parent's house. About 6 weeks ago, I was at my parents', and for some reason, I measured the powerline. (Now I remember, an old powerline volt monitor meter I had in the hamshack room seemed to be reading high. Must be broken, get out a good digital meter to check the voltage. Oh, 128V! That meter is not broken. tried another digital meter, got the same thing.) Told my father, who is also a ham. Called the power company (your standard generic "Public Service Electric and Gas"). "No don't want to talk to billing Dept. Ah, guess I want the line to "downed wires, and other such". Talking to phone answering person: "I think my power voltage is too high." "What's too high?" "The voltage, it's a few volts too high" "Duh, well, we'll send some guys out to check out the, ah, what did you call it?" "the voltage in my house". About a week later, a power company person with a Fluke multimeter visits, and takes the circuit breaker panel off and measures the lines. "yes, you're right, it is too high. What kind of meter did you use? That's just like the ones we use. Must be some bad capacitors on our distribution net. Have to check out the substation." Somehow, the guy broke one of the circuit breakers in the panel. Company says that they'll pay for a replacement. Guy leaves, a few hours later, calls. "try measuring the voltage" "Still too high, 127V." "Found some bad caps, must be more bad ones. This is gonna take us a while to get this figured out" About 4 weeks later, two guys from the power company pay a visit. They go to their kilowatt-hour meter in the basement. "We are gonna take the cover off the meter box and measure the voltage from the street. gotta break this old porcelain seal". So, they break their power security seal, the one they use to keep you from cheating on the electric bill. They measure the voltage, 128V. "We're gonna try a house across the street". Did that, same reading. "gonna check the stuff on the distribution net some more, looks like a tough one to fix." "Don't you have to replace your seal?" "Naw. We'll be back in a few days to take another measurement, takes too long to seal it just to remove it again. we trust that you're not gonna steal power". Next day, one of them returns, takes another measurement, still too high. "I'm gonna have your local pole transformer re-tapped to reduce your line. I removed some caps off the net, but I can't take too many off, or else the other end of town will have too low voltage. We like to set the voltage at 120V at houses." He puts a new seal on the meter in the basement. My father said that he haden't seen the insides of the meter box since 40 years ago, when the house was built. Guess I made the power company guys spend a few weeks work on this. It's not over, yet. About a year ago, I smelled gas next to a mailbox on the streetcorner. Told the gas company, and saw them drilling holes in the ground throughout the neighborhood for weeks looking for the leak. I suppose all the neighbors are wondering why their light bulbs don't seem to last as long as they used to. :-
brian@ucsd.Edu (Brian Kantor) (12/06/90)
Yeah, that's not that unusual. The voltage here in my house right now is 125v, and has been pretty much that for the last seven years. And my lightbulbs don't last real long either. Our mountaintop repeater site had line voltage around 132 volts back in 1971; it's been dropping steadily since and is now down to about 118 - either the lines are aging or it's all the additional load as more equipment gets installed. At work the voltage is a nice 117.5 on two of the three phases. It's about a volt higher on the third; I think there are fewer VAXes on that phase. - Brian
rsd@sei.cmu.edu (Richard S D'Ippolito) (12/06/90)
Excerpts from article <114172@philabs.Philips.Com> by Robert Casey: >I've had a little adventure with the powerline voltage at my parent's >house. About 6 weeks ago, I was at my parents', and for some reason, I >measured the powerline. (Now I remember, an old powerline volt monitor >meter I had in the hamshack room seemed to be reading high. Must be >broken, get out a good digital meter to check the voltage. Oh, 128V! >Guy leaves, a few hours later, calls. "try measuring the voltage" "Still too >high, 127V." >We like to set the voltage at 120V at houses." Yeah, but not too high by much... The typical electric utility tariff (what the utility must provide under its contract with your state government) calls for 120v +/- 5% at your meter, or 114-126 volts. You can't really complain about 126 volts. Also, a 'good' digital (or analog) meter will not necessarily give an accurate reading, as most of them are average-responding, rms-reading, because if there are a lot of solid-state power controls on your feeder, the AC waveform can get fairly chopped up. Rich
jcallen@Encore.COM (Jerry Callen) (12/06/90)
In article <9780@fy.sei.cmu.edu> rsd@sei.cmu.edu (Richard S D'Ippolito) writes: >The typical electric utility tariff (what the utility must provide under its >contract with your state government) calls for 120v +/- 5% at your meter, or >114-126 volts. You can't really complain about 126 volts. Also, a 'good' >digital (or analog) meter will not necessarily give an accurate reading, as >most of them are average-responding, rms-reading, because if there are a lot >of solid-state power controls on your feeder, the AC waveform can get fairly >chopped up. Then what IS the basis for the 120V +/- 5% if not rms? Seems like the only fairly repeatable reading would be peak to peak... BTW, there is all sorts of interesting hash riding on the 60Hz sine wave. Solid state power controls may be the least of the problem; inductive loads can put a lot of crap on the waveform, too. -- Jerry Callen jcallen@encore.com