RCCB (DOUBLE POLE) 100mA

Time and again, we come across many mishaps disrupting human lives due to negligent use of electricity. A large number of industrial and domestic fires are attributed to and caused by electricity. Faulty insulated equipment or wrong usage of electrical devices cause current to flow the insulation to the earth. This is leakage current. This current poses two severe risk factors which are: fire risk & electrocution risk. Residual current circuit breaker provides the function of isolation switching and earth leakage protection of electrical circuits. It also provides the indirect protection of the operator’s body against the dangerous effects of electric current.

Working Principle of RCCB

The RCCB function is based on Kirchhoff’s current law, explained below:

• If the vector sum of incoming current is equal to the vector sum of outgoing current, the RCCB will not trip
• If the vector sum of incoming current is not equal to the vector sum of outgoing current, it indicates a leakage and the RCCB will trip

Due to magnetic imbalance in the transformer of the RCCB, residual magnetism induces a current in the secondary winding coiled around the transformer core which acts on the trip relay. On reaching the trip value (dependent on the rated fault current), this current causes the armature of the magnetic trip to drop out.

The trip operates the lock which opens contacts by way of the energy stored within.

Consequently, all poles of the system are separated from the main system.

The drawn-in-switch-off characteristics of residual current devices with a rated fault current of 10 and 30 mA is proof that these are able to prevent the occurrence of dangerous heart chamber fibrillation. For this reason, residual current circuit breaker with the rated fault current of 10 mA is used for protection of particularly exposed individual equipment.

Residual current circuit breakers with 30 mA rated fault current are already specified for many areas (bathrooms with medical facilities, outside areas, agricultural land etc.)

Sensitivity Selection Chart – RCCB

30mA Tripping current designed for additional protection against direct contact or where specially required by the Indian wiring regulations. e.g.- sockets outside the equipotential zone TT systems, supply to caravan installation etc., the 30mA RCCB protects against leakage currents & indirect contact with earth loop impedance up to 1667 Ohms; for use as additional protection against direct contact, residual tripping current must not exceed 30mA.

100mA Tripping current is suitable for protection against indirect contact & leakage currents for larger installations; the 100mA RCCB operate within 30ms, but doesn’t provide the same level of personal protection as the 30mA units; the 100mA RCCB protects against leakage currents and indirect contact with earth loop impedance up to 500 Ohms.

Smart Features & Benefits:

• Provides protection against earth fault/leakage current and also fulfills the functional isolation.
• Automatically measures and disconnects the circuit when earth fault/leakage current occurs and exceeds the rated sensitivity.
• High short-circuit current withstand capacity – 6kA.
• Dual termination possible for cable and comb type busbar connection.
• Equipped with finger protection disconnection terminals (lP20).
• Fire-resistant plastic parts to withstand abnormal heating and strong impact.
• Independent of line voltage. Also free from external voltage fluctuation.
• Incorporates a filtering device for prevention of nuisance tripping due to transient voltage.