What to do when your RCD or Circuit breaker trips

When it comes to electrical safety, it is extremely important to have various safety devices installed, such as RCD and Circuit Breakers. These devices, when properly installed, protect from electrocution and fire hazards caused by electrical faults. An RCD or Residual Current Device is also called as Safety switch.

switchboard, RCD, Safety switch, circuit breaker

Is an RCD same as a Circuit Breaker?

RCD or Safety Switches are often confused with circuit breakers. While both of these devices protect us from electrical hazards, they are not the same thing.
A safety switch constantly monitors the current flowing through the live and neutral wires. Under normal conditions, the current through live and neutral wires is equal, that means the circuit is balanced. However, if returning current through the neutral wire is not equal to the current going through the live wire, it means a part of the current is going somewhere else. This could just be a current leakage or maybe someone is being electrocuted. Whenever an RCD (Safety switch) detects such an imbalance in live and neutral current, it breaks the circuit almost instantly (within 0.03 of a second).
A circuit breaker basically protects circuits from short-circuit and overcurrent conditions. It detects when the current flowing through is greater than the rated value and cuts off of the circuit. A circuit breaker is not designed to protect an individual from electrocution. So it is important to have safety switches installed in addition with circuit breakers.

What causes an RCD or Circuit Breaker to trip?

When something is seriously wrong with electrical wiring or circuit, the RCD and/or circuit breaker trips disconnecting the circuit from power supply. There are various reasons that can trip a safety switch or circuit breaker.
  • Circuit overload: Overloading of a circuit is the most common reason for tripping your circuit breaker. When a circuit is overloaded it consumes more current. When this increased current reaches beyond the rated limit, the circuit breaker "trips". A safety switch may not trip in case of overload as the circuit still might be balanced.
  • Short circuit: This occurs when the live wire touches neutral wire directly. In this case, a large amount of current flows producing a large amount of heat and may cause a fire hazard. A circuit breaker trips almost instantly in case of short circuits.
  • Ground fault: Similar to short circuit, a ground fault occurs when a hot wire or live wire touches the ground. In this case also, current increases rapidly causing the circuit breaker to trip.
  • Faulty appliance Damaged or faulty appliances can leak excess current. When this leakage current is detected by an RCD or safety switch, it trips and disconnects the circuit.
  • Damaged wiring: Damaged wiring may cause current leakage, ground fault or even short-circuits.
  • Moisture: Current leakage can also occur due to moisture present in electrical switchboards, sockets etc. Wet appliances also produce electrical faults when switched on.
Along with these, there are various other reasons that can produce electrical faults and trip your RCD or circuit breaker.

What to do when your RCD or Circuit Breaker trips?

Resetting a tripped RCD or Circuit Breaker is pretty easy. You just need to flip back the toggle switch to "ON" position. However, it is not a good idea to directly reset the tripped RCD or Circuit breaker without knowing what may have caused it to trip. Following are the steps to figure out the cause of tripping of an RCD or Circuit breaker.
  1. Turn off all the lights and unplug as many appliances as you can. The circuit breaker may have tripped due to overloading of the circuit. So if you directly reset it without disconnecting appliances, there is a good chance of causing the same problem again. Also, if you have recently added and switched on an appliance, make sure to disconnect it before resetting the breaker.
  2. CAUTION! Working with electricity can be dangerous. Never try to touch an electrical panel or any electrical equipment with wet hands. Also, make sure to stand on dry surface with rubber shoes at all times while working with an electrical panel.
  3. Go to your electrical panel and find out which RCD or Circuit Breaker has tripped. This may be easy as you just need to find out which toggle switch has flipped from ON position to OFF position. Once you figure our the tripped device, follow the below steps.
    • First, move the toggle switch to full OFF position (Tripped position is half-way between ON an OFF position).
    • Then move the toggle switch to full ON position. This will restore the power to the circuit.
  4. If the device does not trip again immediately and the power is restored, you can skip to the next step. But if the device trips immediately again, it may be a sign of a fault in wiring or a serious electrical problem. In this case, you need to call a certified electrician to get it checked properly.
  5. After restoring the power, plug in the required appliances one by one and check if the RCD or Circuit breaker trips again. If you plug in a faulty appliance, the device will trip again. Make sure not to overload with too many appliances.

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