Common RMU circuit breaker tripping causes include overload, short circuit, leakage, undervoltage/overvoltage, circuit breaker malfunction, etc. Here's why and quick troubleshooting methods:
Common causes:
Overload: The total power of an electrical appliance in use at the same time in the circuit exceeds the circuit breaker's rated load, causing excessive current and triggering overload protection. For example, operating high power appliances such as air conditioners, water heaters and induction cookers the same time may result in circuit load exceeding the circuit breaker's capacity.
Short circuit: Direct contact between a live wire and a neutral wire (e.g., damaged wire insulation short circuit inside the appliance) can generate a extremely high current (usually several times the rated current), causing circuit breaker to jump immediately. This is one of the most dangerous situations and requires immediate troubleshooting.
Leakage Current: When an electrical device leaks electricity (e.g., the housing is charged) or someone is shocked, some current flows to the ground through the ground wire or people, creating an imbalance between the charged and neutral current (difference is more than 30mA). Leak protectors will cut off power supply in 0.1 seconds for personal protection. Electrical appliances (such as washing machines and water heaters) or aged wiring commonly found in humid environments.
Undervoltage/Overvoltage: Undervoltage trip units can be installed where voltage is unstable to prevent electrical appliances from overloading at low voltage. Overvoltage/undervoltage trip units can also be automatically tripped when the voltage is too high to protect the safe operation of electrical equipment.
Circuit breaker malfunction: If circuit breaker has been in use for a long time (usually 8-10 years), aging of the internal buckle mechanism and oxidation of the contacts may lead to false buckles or failure to recharge. In addition, due to local overheating, loose wires or poor contact during installation can also lead to tripping.
Quick troubleshooting methods:
Preliminary identification of itinerary types:
Overload tripping: After tripping, the circuit breaker handle should be in the ``middle position ''. Wait 5-10 minutes (let overheated components cool), disconnect all appliances and recharge. If re-energizing is successful, gradually turn on the appliance to determine which is causing the overload.
Short-circuit tripping: If the circuit breaker jumps immediately after closing, or if the handle jumps directly to the "open" position, disconnect all electrical appliances and check that the plugs and wires of each appliance are short-circuited (test continuity with a multimeter).
Residual current tripping: If a circuit breaker with remaining current protection (there is a "reset button" next to the handle) trips, press the reset button to close it. If it still jumps after reset, it may be due to an appliance leakage or grounding. Unplug all appliances, plug them back in one by one, and check for faults.
Specific operation procedure: safety operation after power outage: after tripping, first disconnect the master switch, then check the malfunction. Do not operate the distribution box with wet hands to avoid electrocution.
Troubleshooting: Overload: Turn off all appliances, turn off circuit breaker and turn them on one by one. If the circuit breaker jumps when the appliance is turned on, the appliance may be overloaded or malfunctioning.
Short circuit: Unplug all electrical appliances and turn off circuit breaker. If nothing goes wrong after closing, plug the appliances back in one by one. If the circuit breaker jumps after the electrical appliance is plugged in, the electrical appliance has an internal short circuit and needs to be repaired or replaced.
Leakage Current: Unplug all electrical appliances, press the reset button on the Leakage circuit breaker and close. If the shutdown is successful, plug the appliances back in one by one. If a circuit breaker is electrocuted when an appliance is reconnected to the power supply, it indicates that the appliance has a leakage current. Power should be cut, the appliance's grounding wire checked, or sent for repair and testing.
Repairs or replacements: Short circuit/ leakage: Skilled electricians must repair damaged wires or replace aged wires with insulation.
Applied Appliance Fault: Stop using faulty appliances and contact a professional for repair (e.g. washing machine leakage, air conditioning short circuit, etc.).
Circuit Breaker Fault: If all electrical appliances and lines are working, but the circuit breaker still jumps frequently after closing, it may be because circuit breaker is aging. Replace with circuit breaker of the same size and model (brand-name products are recommended to ensure safe certification).
Caution: Do not force circuit breaker to close: Do not repeatedly force circuit breaker to close without troubleshooting after tripping, as this can cause circuits to overheat and start fires.
In high-risk situations, disconnect immediately: If the circuit breaker trips and is accompanied by an unusual odor, spark or hot wire, disconnect the main switch immediately and contact an electrician for assistance. Don't try to operate your own crusher.
Focus on older buildings: For buildings older than 10 years, it is recommended that circuit load and circuit breaker performance be checked by an electrician every 2-3 years and that ageing equipment be replaced in a timely manner.
