What to Do When Your HDB Power Trips

When your HDB power trips, go to your distribution board (DB box, usually near the main door) and look for the switch that has flipped to the OFF position. Unplug or switch off appliances on that circuit, then flip the tripped switch back up. If it stays on, the problem was a one-off overload; if it trips again immediately, do not keep resetting it. Call a licensed electrician.

A trip is your safety system doing its job. Singapore homes use miniature circuit breakers (MCBs) for overloads and short circuits, and a residual current circuit breaker (RCCB), sometimes called the ELCB, that cuts power in a fraction of a second when it senses electricity leaking to earth, often through water or a faulty appliance. Knowing which one tripped tells you a lot about what went wrong.

Where is my DB box and what am I looking at?

In most HDB flats the DB box is mounted high on the wall near the main entrance or in a service area. Open the cover and you will see a row of switches. The larger switch on one side is usually the main RCCB (labelled something like RCCB or ELCB, often with a small T or Test button). The smaller switches next to it are the MCBs, each one protecting a circuit such as lights, power points, the water heater, the aircon, or the kitchen.

Many DB boxes have a simple label sheet inside the cover telling you which switch controls which area. If yours is unlabelled, it is worth mapping it out once so you are not guessing during an emergency.

• RCCB / ELCB: the main earth-leakage protector, trips on water or leakage faults
• MCB: individual circuit breakers for lights, sockets, heater, aircon and so on
• Test button: pressing it should trip the RCCB, confirming it still works

How do I safely reset a tripped switch?

First, switch off and unplug appliances on the affected circuit, especially anything with a heating element or motor such as a kettle, iron, water heater or hairdryer. Make sure your hands are dry and you are not standing on a wet floor. Then firmly push the tripped switch fully back up to ON. Some switches need to be pushed down first before they will go back up.

If power returns and stays on, plug appliances back one at a time. If the trip happens again the moment you plug in a particular item, that appliance is likely faulty and should stay unplugged. If the switch will not stay up at all even with everything disconnected, stop trying and treat it as a wiring fault that needs a professional.

Why does my power keep tripping?

Repeated tripping almost always points to one of a few common causes. Overloading is the simplest: too many high-power appliances on one circuit, such as running an iron, kettle and water heater together. A faulty appliance with a damaged cord or internal short is another frequent culprit, which is why unplugging things one by one helps you find it.

The more serious causes involve moisture and wiring. Water getting into a socket, a light fitting or a water heater can trigger the RCCB, and this is common in bathrooms and kitchens. Aged wiring, loose connections, or a heater with a leaking element can also cause persistent trips. If the RCCB (the main earth-leakage switch) keeps tripping rather than a single MCB, treat it as an electrical safety issue and get it checked.

• Overloaded circuit: too many high-wattage appliances at once
• Faulty appliance: damaged cord, worn plug or internal short
• Water ingress: moisture in a socket, heater or light fitting
• Ageing wiring or loose connections behind the wall

When should I call an electrician instead of resetting?

Reset once. If the same switch trips again immediately, or the main RCCB keeps cutting out, stop and call for help. Other clear warning signs are a burning smell, scorch marks or discolouration around a socket, warm or buzzing switches, sparks when you plug something in, or the whole flat going dark repeatedly. These point to faults that are unsafe to poke at yourself.

In Singapore, fixed electrical wiring work must be done by a Licensed Electrical Worker (LEW) registered with the Energy Market Authority. This is not a DIY job. Replacing wiring, sockets, the DB box or diagnosing a persistent earth leakage requires the right licence, both for your safety and to keep your installation compliant.

Who do I call for HDB power trips in Singapore?

For a fault inside your own flat, such as a tripping DB box, a dead circuit or a faulty socket, you call a private licensed electrician, not the town council. Our emergency electrician service handles exactly this kind of urgent fault, sending a licensed worker to trace the tripping circuit, test the RCCB and appliances, and repair or replace whatever is failing. If it is late at night and the whole flat is dark, an emergency callout gets power restored safely rather than leaving you resetting a switch that will not hold.

There are limited cases where the issue is not yours to fix. If the entire block or several units lose power at once, that is a supply-side or common-area fault for SP Group and your town council to handle. If only your flat is affected, the wiring inside your unit is your responsibility, and that is where a licensed electrician comes in.

• Your flat only, DB box tripping: call a licensed private electrician
• Whole block or several units dark: contact SP Group and your town council
• Burning smell or sparks: switch off the main and call for emergency help

How can I prevent trips in the first place?

Spread high-power appliances across different circuits and avoid running several heat-producing devices at the same time on one socket or extension. Avoid daisy-chaining extension cords, and replace any plug or cable that feels warm, looks frayed or has a loose fit. Keep sockets and heaters away from water and splashes.

Press the RCCB test button every few months; it should trip instantly, proving the earth-leakage protection still works. If it does not trip when tested, that protection may be faulty and should be checked. An electrical safety check every few years, especially in older flats, catches ageing wiring before it becomes a repeated tripping problem.

Frequently asked questions

Is it safe to keep resetting a tripping breaker? No. Resetting once is fine, but if it trips again straight away you are forcing power through a fault. Repeated resetting can overheat wiring and create a fire risk, so stop and get it checked.

Why does only one switch trip and not the whole flat? Each MCB protects one circuit, so a fault on the kitchen or heater circuit trips only that MCB while the rest of the flat stays on. If the main RCCB trips instead, the fault is an earth leakage affecting the whole installation, which is more serious.

Can I replace a tripping socket or breaker myself? No. In Singapore, fixed wiring, sockets and DB box work must be carried out by a Licensed Electrical Worker. Doing it yourself is unsafe and non-compliant.

Who pays for electrical repairs in an HDB flat? For wiring and fittings inside your own flat, you do, as the owner or occupier. Faults in the common areas or the incoming supply are handled by the town council or SP Group.