Will You Lose Power During a Switchboard Upgrade? What to Expect in Sydney

Will you lose power during a switchboard upgrade? Yes, almost every switchboard upgrade needs the main switch turned off for at least part of the job, because the electrician cannot safely work on a live board. The length of that outage depends on the scope of work, but it is genuinely unavoidable for a standard upgrade, and the practical question worth asking instead is how to plan around it rather than whether it will happen.

⚡ Quick Answers: Power During a Switchboard Upgrade

• Why does the power have to go off at all? The main switch has to be isolated before anyone can safely remove or rewire a switchboard, since live conductors inside an open board are a serious shock and arc flash risk.
• How long am I actually without power? It varies with the scope of the job, our guide to organising a switchboard upgrade covers typical timeframes for a standard residential swap.
• Can I keep my fridge and freezer running somehow? Not directly off the board being worked on, though a portable battery pack or a neighbour's power point for a few hours is a common workaround for perishables.
• What if someone at the property relies on medical equipment? Tell us before the job is booked, our backup power for medical equipment guide covers the planning that genuinely matters here.
• Can a generator keep the power on during the works? Sometimes, for a commercial site or a property that genuinely cannot go without power, arranging a temporary generator for the duration of the job is worth asking about at quote stage.
• Does a new switchboard need its own generator connection afterwards? Only if you want permanent backup power, which is a separate job, see our switchboard upgrade for generator guide.

1. Why the power genuinely has to go off

A switchboard is the single point every circuit in the property runs through, which is exactly why working on it safely means isolating the main switch first. AS/NZS 3000 requires that main switch to be clearly identifiable and reachable without climbing, under Clause 2.3.3.4(a), precisely because it needs to be operated quickly and confidently whenever isolation is required. Once that switch is off, everything downstream loses power at the same time, there is no way to keep part of an old board live while the rest is replaced.

This is different to a single circuit being worked on, where only that circuit needs to be dead. A full board swap, a new smart meter provisioned board, or a safety switch retrofit across every circuit all require the whole installation to be isolated for at least the period the main switch itself is being replaced or reconnected.

2. What actually stops working

Everything downstream of the main switch loses power together, your fridge and freezer, lighting, the NBN router and any alarm system not on its own battery backup, garage door motors, and anything plugged into a powerpoint anywhere in the property. Security systems and smoke alarms with a battery backup will usually keep functioning on battery alone, but anything relying purely on mains power stops the moment the switch goes off.

For a typical home this is an inconvenience rather than a hazard, closed fridge and freezer doors hold temperature for several hours, and most residential upgrades are planned to minimise the time without power. For a business, a medical household, or a property with equipment that genuinely cannot lose power, it is worth treating as a real constraint to plan around rather than an afterthought.

3. Planning around a residential upgrade

Tell your electrician in advance if anyone at the property uses home medical equipment, oxygen concentrators, CPAP machines or similar, since this genuinely changes how the job should be scheduled and whether a portable backup is needed for that specific period. Empty perishables you cannot afford to lose from the fridge or freezer the night before if you want extra certainty, keep the doors closed throughout the outage, and let anyone working from home that day know to expect no internet or phone charging for part of the morning or afternoon.

If the property has a boom gate, electric garage door or an intercom system, check there is a manual override before the day of the works, since none of these will operate on mains power while the board is isolated.

4. When a temporary generator genuinely makes sense

For a commercial premises that cannot afford a blackout, a strata building with lifts or fire systems to consider, or a household with a continuous medical need, arranging a temporary generator to bridge the outage is often the most practical option rather than something to just accept. We have arranged this on past jobs, including supplying a small generator for the duration of works on a commercial switchboard replacement so the site never actually lost power, and it is worth raising at quote stage if continuity genuinely matters for your situation.

This is different to installing permanent backup power, which is its own project involving an automatic or manual transfer switch wired into the board so a generator can take over automatically if the grid goes down in future. A temporary generator for the day of the works is a simpler, one off arrangement just to bridge a known, planned outage.

5. What a typical job actually looks like on the day

Your electrician isolates the main switch, removes the old board or the components being replaced, runs and terminates the new wiring and devices, and reconnects and tests the new board before switching back on. Larger jobs, a full rewire of an old fuse box, a three phase upgrade, or a board being relocated, naturally take longer than a straightforward breaker and safety switch retrofit on an existing board in good condition. Our switchboard upgrade price guide covers how scope affects both cost and time on site.

6. After the power comes back on

Once the new board is energised and tested, check that safety switches trip correctly if your electrician demonstrates this, reset clocks and any smart home devices that lost their settings, and confirm your fridge and freezer have come back up to temperature over the following hour or two. If anything seems off, a circuit not working, a breaker that will not stay on, call straight back rather than assuming it will sort itself out, since this is exactly the kind of fault that is easiest to fix while the job is still fresh.

Why it's Level 2 ASP work

Most switchboard upgrades themselves sit within a standard electrician's licence, but any work that touches the point of attachment, the meter, or requires a new supply arrangement needs a Level 2 ASP. If your upgrade is happening alongside a new meter, a three phase change, or any service alteration, that part of the job specifically needs this higher accreditation.

How High Demand Electrical helps

We are a licensed local team, not a call centre, and we plan every switchboard upgrade around minimising your time without power, not just getting the job done quickly from our end. If continuity of supply genuinely matters for your property, a medical need, a business that cannot afford downtime, tell us when you book and we will talk through whether a temporary generator or a staged approach makes sense for your situation, servicing homes and businesses across Sydney's West, South West and Sutherland Shire.

Switchboard Upgrade Power FAQs (Sydney)

Will my internet and phone charging stop working during the outage?

Yes, unless your router and any device you need charged are on a battery backup, both rely on mains power and will stop the moment the main switch is isolated.

Can I ask for the job to be done overnight so I don't lose power during the day?

It is worth asking when you book, though most residential upgrades are scheduled during the day for safety and visibility reasons, see our organising a switchboard upgrade guide for how scheduling typically works.

Does a strata building lose power to every unit during common switchboard work?

Often yes for the common switchboard itself, though individual unit boards downstream may or may not be affected depending on how the building is wired, this is confirmed during the site assessment.

Is losing power during the upgrade a sign something is wrong with my old board?

No, this happens on every switchboard upgrade regardless of the condition of the old board, it is a safety requirement of the work itself, not a reflection of a fault.

If you are planning a switchboard upgrade and want to talk through what to expect on the day, get a switchboard upgrade quote from High Demand Electrical or call 0402 559 777. A site assessment confirms the exact scope, timing and any temporary power arrangements before pricing is locked in.