Low Power From Power Point - Watts Going On?

Discussion in 'Electronics & Electrics' started by Optimus., Feb 5, 2020.

  1. Optimus.

    Optimus. Member

    Joined:
    Jun 27, 2002
    Messages:
    6,374
    Hi,


    I've recently moved and have noticed that my computer and other gear in my office seems slower... I suspected low power based on what I was seeing eg. standing desk pausing/slower, PC boot time longer and monitor turn on time delayed. Electric oven seems poor too.

    Last night I tested my wall socket with the multimeter twice and it showed 165-170v! In fact most plugs did at the back half of the house. The front half plugs showed 248v coming from the wall.

    I looked in the meter box and saw there were 2 safety switches so I believe there's 2 circuits in the house. One switch had '63A' on it and the other '40A' (40A would be on the second 'poor' circuit because there's a stove switch next to it).

    Could someone suggest what's going on and what my next steps should be? I do need some electrical work done shortly so hopefully I can get this fixed at the same time.



    Thanks!
     
    asho444 likes this.
  2. MUTMAN

    MUTMAN Member

    Joined:
    Jun 27, 2001
    Messages:
    7,039
    Location:
    4109
    might be a loose contact somewhere in the swbd might be dirty contacts on a cb or rcd.
    either way time to call a sparky out to go over the swbd and find the problem.
    i wouldnt wait around to fix it either, its a fire hazard just waiting to happen
     
    sTeeLzor likes this.
  3. zero_velocity

    zero_velocity Member

    Joined:
    Sep 16, 2010
    Messages:
    2,648
    Location:
    QLD
    Call a sparky ASAP, worse case is you have a hot joint or even network disconnected neutral connection - both can lead to loss of life if not addressed.
     
  4. OP
    OP
    Optimus.

    Optimus. Member

    Joined:
    Jun 27, 2002
    Messages:
    6,374
    Excellent, ta.

    Part of the sparky coming around is to put in a new circuit so I guess it can be looked at at the same time.
    I did try some isolation testing eg. oven on/off, fridge unplugged etc but power remained low on that circuit.


    Cheers for the help.
     
  5. ArmoureD

    ArmoureD Member

    Joined:
    Sep 12, 2002
    Messages:
    669
    Location:
    Earth
    Voltage drop on a 240v power circuit supplying your pc will not make it slower.

    You definitively have a major issue and that requires a licensed electrician to take a look at.

    Keep us updated. I'm curious to know what it was.
     
  6. OP
    OP
    Optimus.

    Optimus. Member

    Joined:
    Jun 27, 2002
    Messages:
    6,374
    I simplified my PC going slower bit there but it's mostly in the peripherals. Things like the time the monitor takes to turn on after the button is pressed (the time taken can be varied by turning on before and after PC is switched on and drawing power). Also the standing desk is slower/cuts out if the PC is turned on.


    And don't worry - beyond poking my multimeter around, I'm done with it. :D
     
  7. sTeeLzor

    sTeeLzor Member

    Joined:
    Dec 12, 2005
    Messages:
    2,381
    Yeah thats massive volt drop. Curious as well to know the cause. At a guess, theres a loose connection to your wiring in the switch board for that circuit.
     
  8. ArmoureD

    ArmoureD Member

    Joined:
    Sep 12, 2002
    Messages:
    669
    Location:
    Earth
    Do you own the place or are you renting? And what city are you located.
     
  9. OP
    OP
    Optimus.

    Optimus. Member

    Joined:
    Jun 27, 2002
    Messages:
    6,374
    Own & SA.

    Is there a current OCAU member tradies list?
     
  10. aXis

    aXis Member

    Joined:
    Jun 27, 2001
    Messages:
    5,441
    Location:
    Kalgoorlie, WA
    100% a fire hazard, dont use those low voltage outlets until you get it fixed.

    Any current drawn by those outlets will likely cause a large voltage drop over a dodgy junction, which will then get extremely hot.
     
    zero_velocity likes this.
  11. OP
    OP
    Optimus.

    Optimus. Member

    Joined:
    Jun 27, 2002
    Messages:
    6,374
    Would this also be making my electricity use skyrocket? Haven't got a bill yet...
     
  12. MUTMAN

    MUTMAN Member

    Joined:
    Jun 27, 2001
    Messages:
    7,039
    Location:
    4109
    possibly a small amount depending on useage and device
     
  13. ArmoureD

    ArmoureD Member

    Joined:
    Sep 12, 2002
    Messages:
    669
    Location:
    Earth
    I'm in NSW so sorry I can't help you. Keep us posted. Good luck.
     
  14. aXis

    aXis Member

    Joined:
    Jun 27, 2001
    Messages:
    5,441
    Location:
    Kalgoorlie, WA
    Sli
    Slight increase, but not skyrocket.

    If the fault was actually consuming a lot of power, your house would be on fire by now.
     
    zero_velocity and sTeeLzor like this.
  15. RobRoySyd

    RobRoySyd Member

    Joined:
    Jan 24, 2008
    Messages:
    8,091
    Location:
    Sydney
    There has to be another distribution board somewhere as domestic circuits are less than 63A, typically 16A or 20A for power and 8A or 10A for lighting. The 40A circuit probably does feed the stove directly and the 63A feeds another board to split out to the power and lighting circuits.
     
  16. MUTMAN

    MUTMAN Member

    Joined:
    Jun 27, 2001
    Messages:
    7,039
    Location:
    4109

    its likely to be the rcds are separate and downstream of the circuit breakers.
    now days asnz3000 wants individual rcbo's but back in 90s rcds were expensive so youd spec one or two four pole rcd's and split the circuits out through them ANAN
    they were also called earth leakage back then too
     
  17. RobRoySyd

    RobRoySyd Member

    Joined:
    Jan 24, 2008
    Messages:
    8,091
    Location:
    Sydney
    Yes multiple circuits could be run from one RCD however a circuit has to be protected by a current limiting device that'll limit the current to no more than the conductors are rated to carry. For example you cannot connect six 20A conductors to a 63A circuit breaker or fuse. Each conductor must be individually protected.
     
  18. MUTMAN

    MUTMAN Member

    Joined:
    Jun 27, 2001
    Messages:
    7,039
    Location:
    4109
    did you miss the bit where i said
    "downstream of the circuit breakers"
    ?
     
    ArmoureD likes this.
  19. RobRoySyd

    RobRoySyd Member

    Joined:
    Jan 24, 2008
    Messages:
    8,091
    Location:
    Sydney
    Yes I did skim over that but...
    It's pretty unlikely there would be a 63A RCD protecting multiple circuits if its after multiple MCBs. In theory it can be done by running
    all the active and neutral wires through the one current transformer.

    A much simpler explanation is this 63A RCD feeds another board somewhere else in the building. It's probably not even a RCD, rather a MCB.
    The 63A MCB protects the wiring to the sub board. The 40A MCB feeds the stove directly which kind of makes sense.
     
  20. ArmoureD

    ArmoureD Member

    Joined:
    Sep 12, 2002
    Messages:
    669
    Location:
    Earth
    It also could be a 63a rcd down feeding multiple circuit breakers (downstream of the rcd)

    Probably best that the o.p post a bloody picture already instead of us fluffing about in the dark.
     

Share This Page

Advertisement: