Page 1 of 3 123 LastLast
Results 1 to 10 of 23

Thread: intermittent buzzing in electrical panel

  1. #1
    Join Date
    Mar 2016
    Location
    Washington State
    Posts
    70

    intermittent buzzing in electrical panel

    Hi All,

    We do mainly small to medium sized residential PV systems. On occasion we get a customer who notices a buzzing sound in the main panel that comes and goes after the PV install.

    In fact, it happens on my own, in my house. I never really cared much because the panel is nowhere near a bedroom.

    I think it may happen in all our installs(no way to be positive of this) but its only a few who notice the sound.

    Has anyone experienced this?

    thanks

  2. #2
    Join Date
    Jul 2007
    Location
    Clark County, NV
    Posts
    1,098
    How often does it "come and go" and for what duration? I'm not meaning exact numbers, but is it often enough where you can camp and wait for it, and long enough where you can poke around while it's doing it?

    This is especially nice that you can check it out on your own system. Grab a book and a chair.

  3. #3
    Join Date
    Dec 2008
    Location
    Oklahoma
    Posts
    652

    Probably a bad breaker to bus stub connection

    while it is buzzing , use your thumb and "wiggle " each breaker.

    If it starts or stops while buzzing ,then, it is usually that breaker or one adjacent to it.


    Or..

    Turn off the main and remove each breaker and look at the bus-stab connections for burnt ends,
    Also . smell each breaker for that lovely"burnt Tuna flavoring"

    and take a screwdriver and tighten all connections that are not live.

    if it is the Main breaker ,or "live connection" then call an electrician.

  4. #4
    Join Date
    Mar 2016
    Location
    Washington State
    Posts
    70
    [QUOTE

    if it is the Main breaker ,or "live connection" then call an electrician.[/QUOTE]


    I am an electrician.

    the thing is, this has happened a number of times now on different locations. It sounds like a fly is in the panel for about 5-10 seconds

    One customer we had, his panel was in his bedroom so it bothered him a lot. He changed the breaker out twice and it did not fix it. It is directly correlated to when the solar has been installed.

    I do not think it has to do with the inverter because it happens at night as well.

    My best guess is someone to do with the production meter.

    thanks for any further suggestion.

  5. #5
    Join Date
    Jul 2005
    Location
    LA basin, CA
    Posts
    1,805
    Quote Originally Posted by bbartmasse r View Post
    ..It is directly correlated to when the solar has been installed..
    Few months back, a solar contractor reported a similar issue with burning breakers at my local Orange Empire IAEI
    See attached letter regarding SMA inverters with certain Siemens breakers, burning up.

    Dave Moore.pdf
    Roger Ramjet NoFixNoPay

  6. #6
    Join Date
    Dec 2007
    Location
    NE Nebraska
    Posts
    37,098
    AC current has magnetic fields that fluctuate at same rate as frequency of the supply. Anything that can be moved by such magnetic fields - including two conductors in a raceway that have such fields around them are subject to movement by the force of those fields. The higher the current level involved the more likely it is to create such a problem. An object that is trying to change direction 60 times a second will essentially "vibrate".

    Now go to typical loads in a dwelling and often there are not that many constant loads or high level loads, and you only notice such problems when say an AC compressor unit or other larger motor load starts the rest of the time the magnetic fields are low enough there isn't too much noticeable effects. The goal with a solar install is to collect and distribute the unit's rating as much as possible so this sort of becomes a constant load at the units rating as long as there is sunlight to harvest.

  7. #7
    Join Date
    Oct 2009
    Location
    Austin, TX, USA
    Posts
    9,592
    [QUOTE=bbartmasse r;1881891]

    if it is the Main breaker ,or "live connection" then call an electrician.


    I am an electrician.

    the thing is, this has happened a number of times now on different locations. It sounds like a fly is in the panel for about 5-10 seconds

    One customer we had, his panel was in his bedroom so it bothered him a lot. He changed the breaker out twice and it did not fix it. It is directly correlated to when the solar has been installed.

    I do not think it has to do with the inverter because it happens at night as well.

    My best guess is someone to do with the production meter.

    thanks for any further suggestion.
    At night there is (of course) no current in the conductors associated with the PV system, and that includes the PV production meter if there is one. The fact that whatever is causing the buzz started when the PV was installed is, IMO, either a coincidence or due to some other wiring or breaker that was disturbed when the system was put in.

  8. #8
    Join Date
    Dec 2007
    Location
    NE Nebraska
    Posts
    37,098
    [QUOTE=ggunn;1881955]
    Quote Originally Posted by bbartmasse r View Post

    At night there is (of course) no current in the conductors associated with the PV system, and that includes the PV production meter if there is one. The fact that whatever is causing the buzz started when the PV was installed is, IMO, either a coincidence or due to some other wiring or breaker that was disturbed when the system was put in.
    I agree. May have first noticed after PV was installed, and that install may have disrupted something already there. I'd be seeing if this sound coincides with maybe HVAC starting (particularly a compressor unit) or something like that. If it does then you just need to figure out what component related to that is making the noise, maybe just loose fitting components within the breaker supplying that equipment - those magnetic forces are there from the day they get put into service, a component may take a long time to vibrate enough to wear away the plastic it is mounted into - then that allows even more movement and louder vibration noises.

  9. #9
    Join Date
    Oct 2009
    Location
    Austin, TX, USA
    Posts
    9,592
    [QUOTE=kwired;1881960]
    Quote Originally Posted by ggunn View Post
    I agree. May have first noticed after PV was installed, and that install may have disrupted something already there. I'd be seeing if this sound coincides with maybe HVAC starting (particularly a compressor unit) or something like that. If it does then you just need to figure out what component related to that is making the noise, maybe just loose fitting components within the breaker supplying that equipment - those magnetic forces are there from the day they get put into service, a component may take a long time to vibrate enough to wear away the plastic it is mounted into - then that allows even more movement and louder vibration noises.
    Or it could be a long existing condition that the HO just happened to notice after the PV was installed. We have gotten that a few times where the HO is convinced that we "did something" in our installation process that caused some perceived problem where there is no connection whatsoever between what we installed and what he is seeing. We even once had a complaint from a guy who claimed that after we installed PV on his next door neighbor's house his lights flicker - even at night. We always check out these claims - even the neighbor's - but so far not one of them could be traced back to anything we did.

  10. #10
    Join Date
    Sep 2008
    Location
    UK
    Posts
    11,572
    Quote Originally Posted by rt66electric View Post
    while it is buzzing , use your thumb and "wiggle " each breaker.

    If it starts or stops while buzzing ,then, it is usually that breaker or one adjacent to it.
    Not a bad idea. We'd do that with contactors.
    Si hoc legere scis nimium eruditionis habes.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •