Why Does My Safety Switch Keep Tripping?

You’re halfway through dinner and the power cuts out. You head to the switchboard, flick the safety switch back up and everything comes back on. Then it happens again the next day.

A safety switch that keeps tripping is annoying, but it’s also telling you something. Here’s what usually causes it, what you can safely check yourself and when it’s time to get a licensed electrician in.

What a safety switch does

A safety switch, also known as a residual current device or RCD, watches the flow of electricity through a circuit. If it detects current leaking somewhere it shouldn’t, it cuts the power in a fraction of a second. That’s what helps protect people from electric shock.

So when it trips, it’s usually doing exactly what it was designed to do. The question is why.

Common reasons a safety switch keeps tripping

A faulty appliance

This is one of the most common causes. Kettles, toasters, heaters, washing machines, fridges and pool equipment can develop faults as they age. Sometimes the fault only shows up when the appliance heats up or starts a cycle.

Moisture getting in

Water and electricity don’t mix. Outdoor power points, garden lights and anything near a pool or laundry can let moisture in after heavy rain. If your switch tends to trip after a storm, that’s a useful clue.

Too many things on one circuit

Plenty of older homes have a single safety switch protecting several circuits. That means more appliances sharing the same protection and more chances for small leakages to add up.

Damaged wiring

Wiring can be damaged by age, renovation work, rodents or a nail through a wall. This one is a job for an electrician to track down.

A worn out safety switch

Safety switches don’t last forever. Occasionally the switch itself is the problem.

What you can safely check yourself

There are a couple of simple steps that can help narrow it down without touching any wiring.

Unplug and reset

Switch off and unplug the appliances on the affected circuit, then reset the safety switch. If it stays on, plug things back in one at a time. If it trips when a particular appliance goes back in, you’ve probably found the culprit. Stop using that appliance and have it checked or replaced.

Note when it happens

Does it trip when it rains? When the air conditioner starts? Only at night? Jotting it down helps us find the cause faster.

What not to do

Don’t keep resetting it over and over if it won’t stay on. Don’t tape it, wedge it or try to bypass it. Don’t open the switchboard or take covers off. If it trips straight away with everything unplugged, leave it off and give us a call.

When to call straight away

Some situations shouldn’t wait for a convenient day. Get a licensed electrician in as soon as you can if:

The safety switch trips immediately every time you reset it, even with everything unplugged
You notice a burning smell, scorch marks or a warm power point
You’ve had a tingle or a shock from an appliance, tap or power point
Water has got into a power point, light fitting or the switchboard

In these cases, leave the circuit off if it’s safe to do so and keep people away from the affected area until it’s been checked.

Testing your safety switches

Most safety switches have a button marked “T” or “Test”. The NSW Government recommends testing them regularly. A handy reminder is to do it when the clocks change for daylight saving.

Let everyone at home know first, then press the test button. The switch should drop and cut power to that circuit. Reset it afterwards. If it doesn’t trip when tested, or won’t reset, get a licensed electrician to check it.

Does your home have enough safety switches?

NSW Government guidance says homes built from around 2000 onwards will usually have safety switches. If your home is older, it’s worth having it checked. Even then, one safety switch might be covering several circuits.

That’s common in older homes around the Inner West and Eastern Suburbs. Adding safety switches is often done as part of a switchboard upgrade, but sometimes it can be done on its own. We’ll let you know what suits your home.

Safety switches in rentals, strata and commercial properties

Tenants can ask their landlord or agent where the safety switches are and whether they can test them. For landlords, property managers and strata managers, a safety switch that keeps tripping is a good reason to book a check before it turns into a callout.

We work on safety switches in homes, rentals, commercial premises and strata properties across Sydney.

Frequently Asked Questions