150v-155v on US Mains and not all Fuses Used??

Discussion in 'General Electronics Chat' started by Kuhny1, Jul 2, 2015.

  1. Kuhny1

    Thread Starter New Member

    Jul 2, 2015
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    Sorry if doesn't show up right I'm on mobile :/ any way I'm new to the forum and this is my first post, so hi all :D OK so as the title shows I'm having an issue with mains in a camp that was bought on state ground (a state lease camp) I would talk about it more but its off topic. The camp had a lot of water damage before we bought it and it was built I think around the 1970's -1980's. So my dad was the one who bought the camp and I'm helping to gutt it.

    The electrical system is oringinal, that's right lol, a 100A fuse box, no breakers. So my first question goes to the 150-155v mains. I'm completely lost on this. When we were hooking a new light on we wanted to check voltage to see if it was no longer live. It was, and it was way overvolting. So we turned off the switch and I measured it again. It was still hot with 30-33v. I think those are the original switches as well. That might have to do with the "leakage".

    Second question is that not all of the fuses are used. They weren't labeled so we pulled random fuses to see what turned off and made a key as we went. Another strange thing happened. The 240 (which may not be 240 because the 120 is 150) couldn't be turned off and in fact no outlets lost power, no matter what fuse we pulled. We didn't try pulling the block fuses yet. We are going to completely redo the electrical system if need be. Also the was one room that never lost any power either.

    I should mention that the lights that were wired through the switches did turn off when the fuses were pulled, except in that one room I was talking about.

    PS: my multimeter was low on battery but when nothing was connected the read out was 0. I'll check back tomorrow when I go to work on the camp again. I'll put a new battery in and check the mains again. But I doubt that has anything to do with it, because the continuity beep was still solid.
     
  2. tcmtech

    Well-Known Member

    Nov 4, 2013
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    I would start the voltage checks directly from the main power panel and disconnects that are directly tied to your utility meter and do the checks with a multimeter that is known to be working properly.

    If you have anything other than 120/240 +- 10% there or a large voltage imbalance between the two feed lines and the common/ground points for the main service your utility company needs to know about it right away.

    If not and the main supply checks out good then you have major electrical system repairs to do and likely a lot of updating to get things back up to code which it sounds like you do if you have circuits you can not turn off by pulling all the fuses.

    FWIW cheap/stupid people tieing in stuff ahead of the main fuses back in the day was fairly common when they ran out of fuse box capacity and needed additional circuits or needed circuits of greater capacity than the fuse box could handle.

    A buddy of mine moved into his grandparents house a few years ago and helped out with the major wiring redo. At some point in the houses past his grandpa had added an electric water heater but didn't have any fusebox space or capacity left so he simply tied it into the primary feeds ahead of the master fuse so the only way to shut the water heater off was to go out to the main service disconnect in the yard and pull the main beaker for the whole farm which as we found out was so corroded that it would have never tripped on its own. :eek:

    From there I have heard countless other stories of people finding similar things done in old houses and buildings they acquired as well like electric stoves tied in that way and welders, air compressors, large motors and large electric heaters in shops and old barns wired directly to the mains ahead of the buildings old fuse boxes. :rolleyes:
     
  3. Kuhny1

    Thread Starter New Member

    Jul 2, 2015
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    Thanks for that quick reply :) I'll check what you said tomorrow, when you said to check the feed lines you mean the lines coming in before the fuses, right? Also I suspect that the outlets bypass the fuses like you said because there was an old lamp that was left behind and we kept it to use as temporary lighting. The plug was bad and was shorting internally. It was smoking and almost caught fire. If there was a fuse protecting it then I'd imagine that should have blow it right? Also what would you say about the light switches not completely cutting the circuit to 0 volts
     
  4. tcmtech

    Well-Known Member

    Nov 4, 2013
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    I say old wiring does strange things and that's from personal experience.

    Yes check the lines ahead of the fuses at the panels and at the main power box where the utility meter is located as well. If the voltages are good at the utility meter connection panel then everything is on your end and your problem but if its present at the meter panel then your utility company has some work to do first.

    A common issue with finding odd phantom voltages on lines with little to no load is that the old tar saturated cloth coated types of wiring can get damp and allow just enough leakage for a high impedance multimeter like any typical digital one to pick up what is basically a false voltage reading.

    As for what is connected where don't be surprised. If it can make something work someone will have done it no matter what protection systems they had to bypass to make it work.
     
  5. LDC3

    Active Member

    Apr 27, 2013
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    How far is it to the pole transformer?
    If it's over 1000 ft, then the utility company may have set the voltage higher to compensate for line loss. You should check with the utility company to be certain.
     
  6. Kuhny1

    Thread Starter New Member

    Jul 2, 2015
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    Thanks for all of the advice I'll check back tomorrow :)
    Its overvolting to 150, the voltage isn't low
     
  7. ian field

    Distinguished Member

    Oct 27, 2012
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    Does the voltage sink to normal level at the time of day everyone's cooking dinner, boiling kettles and turning the TV on?

    As was suggested - you may have a long cable run and the power company boosts the output to compensate for volt drop.

    Any volt drop will be different at different times of day depending on how much load.

    There's usually some kind of regulation authority that tells power companies what tolerance they must stay within.
     
  8. KMoffett

    AAC Fanatic!

    Dec 19, 2007
    2,574
    230
    On 220VAC feeds with a common neutral, you can see intermittent over voltages if there is a poor neutral contact at the feed from the transformer, either at the transformer or at the panel. This can turn the loads on the two 110VAC sides into a voltage divider. The voltage drop across each "110V" circuit will depend on the load on that side. If both 110v circuits have the same load, then each will have 110V. But if one side has a heavier load, the voltage drop across that side will be less that 110v. The lightly loaded side will have the remainder of the 220V...higher than 110V. Happened in my parents old farm house. They had a couple of areas were lamps would last a couple of weeks or a couple of months. One day during a wind storm my dad saw arcing at the distribution pole in the barn yard. The electrician found a loose neutral. Fixed, and now more blown lamps. :)

    Ken
     
  9. ian field

    Distinguished Member

    Oct 27, 2012
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    Apparently the latest gizmo is an ultrasonic sniffer, basically a transducer like in the old style remote control TVs is amplified and fed to a mixer that down converts it to the audio range.

    The main purpose is for sniffing out corona discharge and any other form of arcing on the insulators of high voltage lines. It would probably also pick up loose connection arcing too.

    Long ago, one magazine published such a project for sniffing out the hiss from a punctured bicycle tyre - I think they missed a trick there!
     
  10. tcmtech

    Well-Known Member

    Nov 4, 2013
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    Unlikely. Voltage drop issues beyond the utilities primary meter and service connection point is not their concern and I have serious doubts they would ever purposely feed something as high a 150+ VAC a customers service to make up for at load voltage drops being ahtt whenever they were not running a specific load the utility company would be over voltaging their systems and would be liable for all damages done to the customers equipment.
     
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