Skip to content
    • Licensed electrical contractor (REC 38187)
    • Lifetime workmanship guarantee
    • Upfront pricing: you get the price before we start
    • 5.0 from 21 Google reviews
    • Family-run, 19 years in the industry
    • Free, no-obligation quotes
    • Based in Altona Meadows, serving Melbourne's west
    • One local team for electrical, heating and cooling
    • Open Mon–Sat, 7am–5:30pm
    Total Comfort Electrical & Air
    Call 03 9116 9050
    Switchboards & safety switches

    Why does my main switch trip?

    Updated 9 October 2026

    The short answer
    Many main switches are only isolators and can't trip on their own. If yours does, it has built-in protection: either a circuit breaker that trips when the whole house draws too much current, or a safety switch covering every circuit. Repeated whole-house trips usually point to an overload, a leaking appliance or a fault at the board or mains, and that needs a licensed electrician to find.

    Overload: the house asking for too much

    A main switch with a breaker built in has a rating matched to your consumer mains. On a cold winter evening, an oven, heaters, a dryer, electric hot water and an EV charger running together can add up to more than it allows, and it trips after a few seconds or minutes. If the trips line up with busy times, note what was on.

    Depending on what the house now runs, the fix might be spreading the load, load management for something like an EV charger, or a switchboard capacity upgrade with heavier mains. Swapping in a main switch with a higher rating isn't safe, because that rating protects the mains cable.

    Leakage: one safety switch for the whole house

    Some boards, often from earlier upgrades, use one safety switch as the main switch, so a leak anywhere in the house blacks out everything, fridge included. The causes are the same as any safety switch trip: a faulty appliance, moisture in an outdoor point or fitting, or tired wiring. Because one device sees every circuit, small leaks from many appliances can also add up. Splitting the circuits across several safety switches or RCBOs stops one fault taking out the whole house.

    When it's the board or the mains

    If the main switch trips with little running, or the board feels warm, buzzes or smells hot, the problem may be a loose connection at the main switch, a failing device or damaged consumer mains. Don't keep resetting it.

    If nothing on the board has tripped but the whole house is dead while the neighbours have power, the fault may be before your main switch, such as the network's service fuse. That needs your electricity distributor or a licensed electrician, not a reset.

    What you can safely do now

    • Switch off big appliances such as heaters, the oven, the dryer and any EV charger before resetting.
    • Reset the main switch once, only if the board is dry, cool and undamaged.
    • If it trips again, leave it off and note the time and what was running.
    • If the board is hot, buzzing or smells burnt, leave it alone, and get everyone out if there is smoke or fire.

    Services that can help

    Switchboard RepairsFaulty breakers, loose connections and damaged boards repaired.Electrical Repairs & Fault FindingFinding out why circuits trip, flicker or go dead, then fixing them.Switchboard Upgrade for Air Conditioning, EV or InductionRoom on the board for a new system, charger or cooktop.

    Read more in our guides

    Related questions

    Sources for this answer

    1 source, with the date each was checked
    1. 1.Energy Safe Victoria: Locate your electricity box outside your home and check whether the safety switch has tripped. If it has tripped, reset the switch. If the switch won’t reset, call a licensed electrician. Accessed 30 September 2026.

    General information for homes in Victoria. Every installation is different, so treat this as a starting point. Where this answer refers to Victorian safety or rental rules, the sources above have the current requirements.