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12071 Views 4 Replies Latest reply: Apr 7, 2015 11:44 AM by Robert_B RSS
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Jun 9, 2014 9:30 PM

Power Fluctuations at Home

Hello everyone!


I just have a quick question, the place I'm living in has two power sources. One from a generator to power lights and other lower power appliances while the other source is the local power company for appliances that require large supply like Airconditioning units, etc. The Neutral for both is joined in the same power house.


We have always been experiencing fluctuations and am wondering if this is because their neutrals are joined? How would i stop it? Could we install a voltage regulator or something?

I'm not very knowledgable with these things so help is much appreciated.



  • LanceLK Novice 42 posts since
    Apr 4, 2014
    Currently Being Moderated
    Jun 10, 2014 10:58 PM (in response to Riley)
    Re: Power Fluctuations at Home

    Hi Riley,


    There is absolutly nothing wrong with joining the neutrals. Actualy, all neutrals connect with each other eventualy, so there is no problem there. I think the problem is the regulation of either your local power company or your generator. Are the fluctuations a normal occurence? Or did it just happen recently?


    You might also want to check with other people who rely solely on the Power Company and see if they are experiencing any fluctuations. If not, then it probably is your generator. Is it old? You might need to have it checked, or install a regulator at the very least.





    I found this pdf online and you might be interested in reading for additional clarification.


  • WiNorthOutdoors Novice 2 posts since
    Jun 14, 2014
    Currently Being Moderated
    Jun 14, 2014 4:42 PM (in response to Riley)
    Re: Power Fluctuations at Home

    Had similar issue in new house, lights dim when geothermal compressor kicks on.  The power company replaced the transformer feeding mine and neighbors house.  For you maybe the generator is also undersized.  If your house is older than 4 years, I recommend retighten all the mains and breaker connections in the panel.  Even new, the wires expand and contract under load and require maintenance regularly - this is one of the reasons older housed burn down.  Also check for any type of junction box along the route where a splice may occur (seen it, almost burned down apartment with students, arcing over time, charred wood above the metal box and the metal connecting components destroyed).  Any splice could be loose, ideally remove and run full length wire without splice.

    If  you have fuse panels, other issue could be possible.  Even breakers can go bad.  See if you can trace down what equipment is activating when power drops.   If house is from the early 80's (I think) there could be aluminum wire, which has reduce current carrying capacity, which will also has a greater impact on the screw connections in the electrical panel of being loose.  When I check other peoples panels, it's not uncommon to find 30-50% of the screws on the breakers to be anywhere from 1/4 to 1/2 turn loose.

  • utap Novice 1 posts since
    Jun 27, 2014
    Currently Being Moderated
    Jun 27, 2014 12:07 PM (in response to Riley)
    Power Fluctuations at Home

    Your question needs clarificatiion please.

    "We have always been experiencing fluctuations"  Which power supply are you referring? The one supplying lighting is easier to validate

    fluctuations because the lights dim. That makes it a possible generator issue! Not a power company isssue.


    What do you mean by "fluctuations"? Dimming lights from the generator supply? How serious are the dips. Have you put a volt meter to monitor?


    Having been an electrical power engineer for 8 years with a power company, the reliability of power company feeds,though not impeccable,

    are very "robust" and designed to NOT give fluctuations unless heavy motors are being started from an adjacent industrial park.


    I can't make any recommendations w/o more information.


    Control Engineer


  • Robert_B Novice 2 posts since
    Apr 7, 2015
    Currently Being Moderated
    Apr 7, 2015 11:44 AM (in response to Riley)
    Power Fluctuations at Home

    I agree with TAP but one thing comes to my mind is the ground connection from house to grid; if it's loose, you may end up with line unbalance (?)

    Good lock

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