Power Logging Sydney: Can Your Building Handle EV Chargers?

Can your building actually handle EV chargers, more solar or a new commercial kitchen? A power logging study answers that with data instead of guesswork. A recording instrument measures your building's real electrical demand for seven days, and the result tells you how much spare capacity the switchboard and consumer mains genuinely have before you spend a dollar on hardware or upgrades.

⚡ Quick Answers: Power Logging

• What is power logging? A professional-grade logger is installed at your switchboard to record voltage, current and power on every phase for seven days.
• Why seven days? One full weekly cycle captures weekday peaks, overnight troughs and weekend patterns, so the measured maximum demand reflects how the building really runs.
• Why not just calculate it? Paper calculations for existing buildings are often conservative. Measured demand is frequently well below the theoretical figure, which can mean you already have the capacity you need.
• Does the power go off? Only briefly. Installing the logger's clip-on sensors typically takes about 30 minutes on a planned outage, then the building runs as normal all week.
• Who does it? A Level 2 electrician handles the study end to end. Network-side upgrades, if the data shows you need one, involve Level 3 design and Level 1 construction.

1. Calculated vs measured maximum demand

Every electrical design starts with a maximum demand calculation: the designer adds up the loads and applies diversity factors from the Wiring Rules to reach a theoretical peak. That approach is right for new buildings, where no history exists. For existing buildings it is often conservative, because not every apartment runs the oven, aircon and hot water at once. The gap between the paper figure and the measured one is exactly where a logging study creates value. If you want the concept behind the calculation itself, our free maximum demand calculator on this page and the maximum demand explainer cover it.

2. What a logging study reveals

The report shows the real peak your building hits in amps and kVA per phase, when those peaks occur, the overnight and weekend troughs, and how much headroom remains in the switchboard and mains. From our own studies across Sydney, measured peaks in residential strata buildings commonly land well below the calculated figure, which is why many blocks can support a shared EV charging system with load management and no mains upgrade at all. Commercial buildings dominated by daytime HVAC often have generous overnight capacity, which is exactly when EVs want to charge.

3. Why Sydney buildings are ordering studies now

Three trends drive it. EV charger rollouts in strata blocks, car parks and fleet depots add a significant continuous load the original design never imagined; our EV ready provisions guide and 3 phase EV charger guide cover the home end of that story. Electrification replaces gas with induction, heat pumps and electric hot water, stacking new load onto old boards. And solar or battery applications above certain sizes often need real load data before Ausgrid or Endeavour Energy approve the connection. Not sure which network your building is on? Check your network area in seconds with our postcode checker.

4. How the study runs

We attend site and install the logger at the main switchboard or sub-main using non-intrusive clip-on current transformers, typically a 30 minute job on a brief planned outage. The building operates normally while the logger records for seven days. We then collect it, analyse the data and deliver a written report with the measured maximum demand, the spare capacity, and a clear answer on whether your planned load fits. Allow two to three weeks from first call to report in hand.

5. What happens if you need more capacity

The logging itself is a Level 2 job with no network involvement. The follow-up can be different: if you need substantially more capacity than the existing supply can deliver, the network side may need upgrading, which means a Level 3 ASP designs the solution and a Level 1 ASP constructs it. That is the exception rather than the rule, and it is precisely the expensive step a logging study either justifies with evidence or saves you from entirely. See our Level 3 design and Level 1 network installation services for how that path works.

6. The two mistakes logging prevents

Over-upgrading: spending big on supply works because the paper calculation said you were at capacity when the real peak was far lower. Under-upgrading: adding load unmeasured and buying yourself nuisance tripping, blown service fuses or a defect notice. A week of data costs a fraction of either mistake. If a big new load does go ahead, remember that load increases can trigger a Notification of Service Work with your distributor.

How High Demand Electrical helps

We run 7 day power logging studies across Sydney as a standard Level 2 service: install, retrieval, analysis and a written report you can hand to a strata committee, installer or the network. Because we also hold Level 3 design and Level 1 construction accreditation, we can carry the rare job that needs a genuine supply upgrade all the way through power supply upgrades and switchboard upgrades without handing you between contractors.

Power Logging FAQs (Sydney)

How much does a power logging study cost?

It depends on the site and metering arrangement, so we quote each study fixed-price after a quick phone walkthrough. It reliably costs a small fraction of an unnecessary capacity upgrade.

Will the building lose power during the study?

Only during the brief planned outage while the logger is connected, typically around 30 minutes. The seven recording days run with everything operating normally.

Can a home order a logging study, or just buildings?

Homes can, though most houses get their answer faster from an assessment and a maximum demand calculation. Logging earns its keep on strata blocks, commercial sites and anywhere the paper numbers look tight. See our home EV charger cost guide for the residential path.

Is the report accepted by Ausgrid and Endeavour Energy?

Measured load data is exactly what networks want to see attached to connection applications that need it. We prepare the report so it supports your application rather than raising new questions.

Want the real number?

Get a power logging study quote from High Demand Electrical, or call 0402 559 777. Every study starts with a site assessment so scope and pricing are confirmed before work begins.