What Happens on the Day of a Supply Upgrade

A consumer mains or supply upgrade is not a mysterious job, but it does involve your power being off for a chunk of a day, and a distributor whose schedule you do not control. Knowing the sequence makes it much easier to plan around.

This is what actually happens, in order, and what is worth doing before the van arrives.

Before the day: the part that takes the longest

The electrical work is usually the short part. What sets the date is the process around it.

The assessment. Somebody looks at the existing supply arrangement, the mains, the board, the metering and the route. The output is a scope, and on an older property it should also name the things that could change once the cover is off.

The maximum demand calculation. This is what decides the answer, and it is worth understanding because it is the difference between a real assessment and a guess. Maximum demand is a calculated estimate of the greatest load the property will draw under normal operation, based on what is actually connected and what is planned. It determines whether you stay single phase, whether the mains need upsizing, and whether three phase is genuinely warranted.

Plenty of properties that think they need three phase need bigger single phase. The calculation tells you which, and it is a different question from whether your switchboard is old.

The distributor application. Connection work requires an application to the distributor, and it has its own lead time which does not compress because you are ready. This is also why confirming which network your address is on matters: Ausgrid and Endeavour Energy have different processes, and an application prepared for the wrong one goes nowhere.

The outage booking. Where the supply has to be disconnected at the network side, a window gets booked. This is normally what fixes the date.

Five things worth doing before the day

1. Sort out anything that has to stay running. Medical equipment is the important one; if anyone in the house depends on mains-powered equipment, say so when booking, not on the morning. For most households the real questions are the fridge, the freezer and working from home.

2. Deal with the freezer properly. A full freezer left shut holds for a good part of a day. Turn it to its coldest setting the night before, do not open it, and do not bother with the fridge contents beyond that. If the outage is a long one, a chest freezer full of food is worth moving.

3. Clear access to the board and the mains route. This is the one that actually delays jobs. Whatever has accumulated in front of the meter box or switchboard needs to be somewhere else. If the mains route runs through a garage, a wardrobe or along a fence line, that needs to be reachable too.

4. Plan the day around no power. No lights, no kettle, no internet, no hot water if it is electric, and no garage door if it is powered. Charge what needs charging. If you work from home, work elsewhere for the day.

5. Sort out pets and gates. Somebody needs access to the meter position and the route all day, including the side gate. Dogs and open gates are a bad combination.

The day itself, in order

Arrival and confirmation. The scope is checked against what is actually there before anything is disconnected. On older properties this is where surprises surface, and it is better for them to surface now.

Isolation and disconnection. The supply is disconnected at the network side. Only an accredited Level 2 ASP can do this, and it is the reason the job needs one at all. From this point the property is dead.

The new work. New consumer mains run, new board or new main switch fitted where it is in scope, metering installed or transferred, and terminations made.

Testing. Insulation resistance, earth continuity, polarity, RCD operation. This is not a formality; it is the part that the certificate certifies, and it is why the job takes longer than the installation itself suggests.

Reconnection and energising. The supply is reconnected and the installation brought back on. Circuits are checked and the board labelled.

Paperwork. A CCEW, the Certificate of Compliance for Electrical Work, is issued by the licensed person who did the work and lodged within 7 days of the compliance test. From 1 July 2026 that lodgement is online only, through the Building Commission NSW eCert portal. You get a copy, and you should keep it; it is what you hand over at sale.

Because this job involved the connection, a NOSW, a Notification of Service Work, also goes from the ASP to the distributor. Two documents, not one.

What to check before we leave

Worth doing while somebody is still there:

• Every circuit is back on, including the ones nobody uses. Check the oven, the hot water, the air conditioner, the garage door, the pool pump, the irrigation controller.
• The board is labelled, and the labels are right.
• Press the RCD test buttons. They should trip instantly.
• Reset the clocks you care about and check anything with a battery backup came back cleanly.
• Ask for the CCEW, or ask when it will arrive.

What can change the scope on the day

On a property built before about 1990, these are the realistic ones, and a good quote mentions them rather than discovering them:

• Insulation on existing circuits too brittle to be disturbed and reterminated
• An asbestos backing panel behind the equipment, which changes the method
• Aluminium tails needing a proper transition to copper
• The mains route turning out to be blocked, collapsed or not where it was assumed to be
• Existing defects that have to be rectified before circuits can be reconnected

None of these are unusual. What matters is whether they were flagged as possibilities at quote stage.

Frequently asked questions

How long will the power be off? Most of a working day is a reasonable expectation for a mains and board job. The booked outage window is the number to plan around, and you will have it in advance.

Do I need to be home? Someone needs to provide access at the start and preferably at the end to walk through the circuits. You do not need to be there for the middle of it.

Will the street lose power too? No. This is your service, not the network.

What if it rains? Work involving open supply equipment does not happen in the wet. It gets rescheduled, which is frustrating but not negotiable, and it is another reason the outage window matters.

Can I upgrade the mains without upgrading the board? Often yes. They are separate parts of the installation and the assessment can call for one and not the other. The reverse is also true: plenty of switchboard jobs need no mains work at all.

Do I need three phase for an EV charger? Usually not. Most home chargers run on single phase. The question is whether the existing supply can carry the charger alongside everything else, which is the same maximum demand question. Where the supply is the constraint, the options are upgrading it, load management, or a lower charger output.

Why does this need a Level 2 electrician when my electrician could do the board? Because disconnecting and reconnecting at the network side, and altering the mains or the metering, is connection work. A licensed electrician can do everything on your side of it. The dividing line is worth understanding.

Booking one in

If your lights dim when the air conditioner starts, or you are adding load and want to know whether the supply carries it, the first step is the assessment rather than the quote.

Call 0485 824 714. We are accredited Level 2 ASPs under the NSW Government's ASP Scheme, authorised to work on the distribution network, with 15 years on connection-side work and a Lifetime Labour Warranty on what we do. Free quotes, across Sydney and the Blue Mountains on both the Ausgrid and Endeavour Energy networks.