How Much Does an RCD Safety Switch Cost in Perth? (2026 Prices)

An RCD — residual current device, or safety switch — is the device that turns a fatal shock into a trip. It watches the current going out and coming back on a circuit, and if even 30 milliamps leaks to earth (through a person, a wet appliance or a damaged cable) it cuts the power in under 300 milliseconds. Circuit breakers and fuses don't do this; they protect the cable from overload, not you from electrocution.

Western Australia has some of the strictest RCD rules in the country, written after a run of deaths in older homes. This guide covers what RCDs cost to install in Perth in 2026, what the law requires when you sell or rent, what's done on the day, and why a safety switch keeps tripping.

The RCD itself is $40–$90 at trade for a quality 40 A or 63 A unit; the rest of the price is the electrician's time to isolate the board, rearrange the circuits so the load splits sensibly, terminate, test every RCD's trip time and do the certificate. A $60 unit from a hardware store isn't the saving it looks like — installation is licensed work in WA, and the test is the part that matters.

• Circuit breaker — protects the wiring. Trips on overload (too many appliances) or a short circuit. Does nothing for a person touching a live part.
• RCD (safety switch) — protects people. Trips when current leaks to earth, at 30 mA, in a fraction of a second. In most Perth boards one RCD sits in front of two or three circuits.
• RCBO — both in one unit, per circuit. When something faults, only that circuit trips and you know exactly where the problem is. It's what we fit in any board we upgrade, and what the Wiring Rules push new work towards.

If you're adding RCDs to an existing board, the usual answer is two or three RCDs covering the power and lighting circuits. If you're upgrading the board, RCBOs on every circuit cost a little more and save you every time the toaster trips half the house.

• Selling. Under the Electricity Regulations, a home must have at least two RCDs protecting all power-point and lighting circuits before the title transfers. The seller is responsible, and penalties apply. Settlement agents in Perth check for it as a matter of course.
• Renting and short-stay. Landlords must have the RCDs installed before a tenancy starts, and short-stay hosts before guests stay. Property managers will ask for evidence.
• Maximum three circuits per RCD. This is why "two RCDs" often becomes three or four on a larger home: with a pool, ducted aircon and a shed, the circuits don't fit under two devices.
• New work since 1 January 2019. AS/NZS 3000:2018 requires RCD protection on all final sub-circuits — including hard-wired appliances such as ovens, cooktops, hot water units and air conditioners — for any new circuit or alteration. That's a reason new circuits often come with an RCBO.
• Licensed contractor only. RCDs are switchboard work; a licensed electrical contractor (our licence is EC15449) must install them and give you an Electrical Safety Certificate within 28 days.
• Test every three months. Building and Energy recommends pressing the "T" button on each RCD every three months (or as the manufacturer says, whichever is sooner). If the power doesn't drop, call an electrician.

Selling or renting soon? Our WA electrical compliance checklist covers RCDs, smoke alarms and the certificate in one place.

1. Look at the board. Type of enclosure, spare ways, how the circuits are grouped, whether the earthing and MEN link are sound. A photo beforehand usually tells us most of this.
2. Plan the split. Circuits are divided across the RCDs so no device carries more than three, and so a trip doesn't take out the fridge and the lights together.
3. Isolate and install. Main switch off, RCDs fitted on the DIN rail, circuits re-terminated through them, neutrals moved to the RCD's neutral bar (the step handymen miss — a shared neutral makes an RCD trip constantly).
4. Test. Every RCD gets a trip-time and trip-current test with a calibrated tester, plus polarity and earth continuity checks on the circuits behind it.
5. Label and certify. Updated circuit labels, and your Electrical Safety Certificate — the document your settlement agent or property manager wants.

Two RCDs on a modern board is about an hour and a half. Power is off for most of it.

An RCD that trips is usually doing its job. The common causes we find across Perth:

• A faulty appliance — old fridges, kettles, toasters, washing machines and heaters with a damaged element or moisture inside. Unplug everything on the circuit, reset, plug things back one at a time.
• Moisture — outdoor power points, garden lights and reticulation controllers after rain; bathroom fans; a leaking hot water unit.
• Too many circuits on one RCD — small leakages from several appliances add up and cross the 30 mA threshold.
• Damaged cable — rodents in the roof, a nail through a cable, old perished insulation.
• A worn-out RCD — they don't last forever; 15–20 years is a good run.
• A wiring fault — a borrowed or shared neutral from a previous DIY job.

Our guide to why a safety switch keeps tripping goes through the checks you can do yourself. If it still trips with everything unplugged, that's fault finding — we quote it as a fixed price, not by the hour.

• The board. A modern enclosure with spare ways is a quick job; a full board needs an extension; a ceramic-fuse board can't take RCDs and needs upgrading.
• How many circuits. More circuits means more RCDs to stay under three per device.
• Circuit rearranging. Old boards often have odd groupings — lights and hot water on one fuse — that need sorting before RCDs go in.
• Earthing problems. A missing MEN link or a corroded earth stake has to be fixed for RCDs to work reliably.
• Fault finding. If an RCD is tripping already, the fault has to be found first or the new device will trip too.
• Bundling. RCDs plus smoke alarms plus the compliance certificate in one visit is cheaper than three visits.

Stick with the established switchgear brands sold through Perth electrical wholesalers — Clipsal, Hager and NHP are the common ones. They're made for the fault levels on Western Power's network, spares stay available for the life of the board, and they fit standard DIN-rail enclosures. Skip unbranded units bought online: an RCD is life-safety equipment, and every one we install gets a trip-time test with a calibrated tester before we leave.

Send a photo of the open switchboard — that's usually enough for a fixed price the same day. Tell us if it's for a sale or a tenancy and we'll include the compliance check and certificate.

• Fixed price before we start, $0 call-out fee.
• Same-day or next-day for sale and tenancy deadlines where we can.
• Every job includes a trip-time test on every RCD and the Electrical Safety Certificate.
• Licensed electrical contractor EC15449, 300+ five-star Google reviews. See our RCD and safety switch service and RCD testing page.

We fit and test RCDs across the Perth metro, from Morley, Dianella and Bayswater to Fremantle, Rockingham and Midland.

• Do it before the settlement rush. A booked job is cheaper and calmer than an urgent one the week before settlement.
• Bundle the smoke alarms and the certificate into the same visit.
• Fix the tripping cause first. Unplug suspect appliances before we come; if the RCD holds, it's the appliance, not the board.
• If the board is old, upgrade it once rather than paying to add RCDs to a fuse board that will need replacing anyway.

Need RCDs installed or tested in Perth?

Send a photo of your switchboard or call 0422 117 839. Fixed price, $0 call-out fee, tested and certified. You can also request a free quote online or read about our RCD and safety switch service.