Today I had a power strip short out. The load on it wasn't very heavy at all. Just a tv, bose audio system, sat receiver, and dvd player. I measured the outlet feeding it and got 142 volts. I know house voltage fluctuates a little, but 142 volts seems like a lot to me, especially when the nominal value is supposed to be 120 volts. I think Alabama Power will be receiving a service call from me.
+- 5% is not uncommon where I live
can vary depending on time of the day/night
and if is weekend or not
I think some mains power suppliers promise that mains voltage
according to delivery terms
should be within +- 10% of nominal
For 120 VAC this would be +- 12V
giving maximal variation within: 108-132
142V, if your meter shows correct value, is definitely too much.
It is almost 20% above nominal.
It is plain dangerous, as some household equipment may overload and cause fire.
And in best case plenty of fuses will be blown for many people.
Send in all blown fuses and require new in compensation!
can vary depending on time of the day/night
and if is weekend or not
I think some mains power suppliers promise that mains voltage
according to delivery terms
should be within +- 10% of nominal
For 120 VAC this would be +- 12V
giving maximal variation within: 108-132
142V, if your meter shows correct value, is definitely too much.
It is almost 20% above nominal.
It is plain dangerous, as some household equipment may overload and cause fire.
And in best case plenty of fuses will be blown for many people.
Send in all blown fuses and require new in compensation!
I’m in South Africa – Cape Town region
Our Voltage standard is from 220v to 240v never higher than that
But in my place where I stay, it’s 230v and then all the people put on the ovens or heaters in the town it drops to 229 and lower, so it changes every time but never drops below 220 or go higher than 240, it never goes up to 240v not even if the operators is drunk.
And we have a power factor of 49.9%
Our Voltage standard is from 220v to 240v never higher than that
But in my place where I stay, it’s 230v and then all the people put on the ovens or heaters in the town it drops to 229 and lower, so it changes every time but never drops below 220 or go higher than 240, it never goes up to 240v not even if the operators is drunk.
And we have a power factor of 49.9%
Hi,
here in the UK we are 216 to 254 for a nominal 230 or 240Vac.
I often measure 246 and 238 but rarely outside these limits. But I design for 216 to 254.
Half our UK voltages and your 142V is way outside a reasonable tolerance.
COMPLAIN and ask for an explanation and if they cannot explain the event demand monitoring. There is something wrong
here in the UK we are 216 to 254 for a nominal 230 or 240Vac.
I often measure 246 and 238 but rarely outside these limits. But I design for 216 to 254.
Half our UK voltages and your 142V is way outside a reasonable tolerance.
COMPLAIN and ask for an explanation and if they cannot explain the event demand monitoring. There is something wrong
They will usually respond in one day for overvoltage. The power company has liability insurance too.
You can imagine how bad it could be for them if 'over-voltage' was found to be blowing their customers stuff up, and setting houses on fire.
Ihad the same issue as you,and the 142Vac blew my Belles 450 amp up at 3:30 in the mornig a while back. The amp was highly modified, at 300,000uf of capacitance. The rails were running at ~110VDC!, instead of the proper 80VDC. (modded it was floating at 89dc) A capacitor blew istself to smithereens. Magic smoke everywhere..and the amplifer kept playing through it all..until the 15amp slow blow 120vac power fuse blew. about 15 seconds later.
lessee...~110vdc x .7=75.6/8=9.45x75.6=~715wpc. uhm.... err..ok.
No wonder I seemed to have limitless headroom.
It was spectacular. I called, and the power company was there, lowering the voltage on the transformer, at 8:15 the ver next morning. That's 5 hours later. (I left the complaint at 3:30am)
You can imagine how bad it could be for them if 'over-voltage' was found to be blowing their customers stuff up, and setting houses on fire.
Ihad the same issue as you,and the 142Vac blew my Belles 450 amp up at 3:30 in the mornig a while back. The amp was highly modified, at 300,000uf of capacitance. The rails were running at ~110VDC!, instead of the proper 80VDC. (modded it was floating at 89dc) A capacitor blew istself to smithereens. Magic smoke everywhere..and the amplifer kept playing through it all..until the 15amp slow blow 120vac power fuse blew. about 15 seconds later.
lessee...~110vdc x .7=75.6/8=9.45x75.6=~715wpc. uhm.... err..ok.
No wonder I seemed to have limitless headroom.
It was spectacular. I called, and the power company was there, lowering the voltage on the transformer, at 8:15 the ver next morning. That's 5 hours later. (I left the complaint at 3:30am)
I opened up the shorted power strip. It was all black inside. Apparently the overvoltage caused the MOV inside to fail, putting a dead short across the hot and neutral lines. I wasn't there when it happened. I imagine there was a pretty loud bang and a big release of the magic smoke in the process. The breaker in the strip and the branch circuit breaker both kicked in the ordeal.
Hey Bamma. I think that MOV did you a favor. It surprising that more stuff didn't fail at 143 volts.
Glad to hear that you got it fixed, that voltage was WAY over what they the power company should supply. Nice to know they were prompt in replacing the transformer.
For others who may have over/under voltage problems. I have had the power company come out and monitor voltage at several sites. They were all commercial sites (USA and Europe), but they should do it for home service too. This is a case where you DON'T want more than you payed for!
Glad to hear that you got it fixed, that voltage was WAY over what they the power company should supply. Nice to know they were prompt in replacing the transformer.
For others who may have over/under voltage problems. I have had the power company come out and monitor voltage at several sites. They were all commercial sites (USA and Europe), but they should do it for home service too. This is a case where you DON'T want more than you payed for!
Stable? line voltages..
We have a major problem down here...Our 220 VAC comes & goes frequently , the other day the lights started tweaking & the shutdown protocol started again, shut off all electronics....soon the voltage dropped all lights to a dull glow...measured out at 87 volts AC, stayed that way for at least 24 HRS!
_______________________________________Rick........
We have a major problem down here...Our 220 VAC comes & goes frequently , the other day the lights started tweaking & the shutdown protocol started again, shut off all electronics....soon the voltage dropped all lights to a dull glow...measured out at 87 volts AC, stayed that way for at least 24 HRS!
_______________________________________Rick........
This problem also caused a far more impressive failure that I witnessed first-hand. This occurred before the power strip incident, before I found out about the overvoltage problem. 143 volts leg to neutral equals 286 volts leg to leg. I went out to the garage to use the air compressor and found its pressure gauge at zero psi. I opened up the breaker panel in the garage and found the 20 amp double pole breaker for the compressor had tripped (it's a 240 volt compressor). The garage panel is fed from a 60 amp double pole from the main 100 amp breaker box inside the house. I reset the breaker and immediately the compressor started up and ran fine. No obvious signs of malfunction. The only sound was the air-pumping noise it normally makes. I let it run until the gauge read about 40 psi then manually threw the breaker to "off" then back to "on" to see what would happen. The result was a bright flash of orange light and a loud bang from the pressure cycling switch. Apparently the overvoltage caused it to short out. The leg to leg fault tripped three breakers at once, the 20 amp breaker for the compressor, the 60 amp breaker for the garage feed, and the 100 amp main for the whole house. I can only imagine the current that was flowing in the split second before the breakers tripped. After changing out the cycling switch, the compressor works just fine.
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.