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Circuit Breaker Keeps Tripping? Get Professional Fault Diagnosis.
When the distribution board switch trips repeatedly, forcing it back up can damage your wiring. Repair Service SG provides expert testing for RCCBs, MCBs, main switches, and DB box terminals across Singapore homes.
Tell us which switch is tripping in your distribution board.
Understanding Your DB Box
Singapore electrical installations rely on distinct protective devices in your consumer unit. Understanding which one tripped explains the underlying hazard.
Measures the current balance between live and neutral. If even 30mA leaks into the earth conductor (or a human body), it trips instantaneously to prevent electrocution. Replaced older voltage-operated ELCBs in modern Singapore homes.
Protects individual wiring circuits against electrical overload and short circuits. For example, a 16A MCB protects water heater wiring, while 10A MCBs protect lighting loops. Only cuts power to its designated zone.
The primary manual disconnect switch for the entire property (usually rated 40A or 63A single-phase). It mechanically cuts all incoming electrical supply from SP Group.
Swapping a circuit breaker without testing the circuit is dangerous because if an underlying wire fault exists, the new breaker will just trip again or overheat.
Never attempt to open the dead-front cover of your electrical distribution board to poke wires or tighten live terminals. A standard residential supply delivers 230V AC at up to 63A, which carries lethal shock risk. If a breaker trips repeatedly, turn off the affected circuit and allow our technicians to diagnose the fault with insulated, calibrated instruments.
Message our team with a photo of your DB box for quick advice.
Answers
The "T" or "TEST" button creates a controlled internal current leakage to confirm the mechanical trip latch is not stuck. Pressing it should make the RCCB trip immediately. If pressing the test button does nothing, the RCCB is defective and will not protect you during an electric shock, requiring prompt replacement.
Yes. Older homes in Singapore still have legacy voltage-operated ELCBs that can fail to trip if the earth rod resistance is high. Upgrading to a modern current-operated RCCB dramatically improves household shock protection.
In most cases, only the specific worn-out MCB or RCCB module needs replacement, keeping costs economical. Complete distribution board replacement is only required if the main busbar is severely oxidized, burnt, or if the board is outdated and lacks modern DIN rail capacity.
Under Singapore Standard SS CP 5 / SS 638, standard ratings are: 6A or 10A for lighting circuits; 16A or 20A for storage water heaters and aircon circuits; 16A or 20A/32A for 13A socket radial/ring circuits; and 40A or 63A with 30mA sensitivity for the main RCCB.