Enquiry  |  Contact Us  |  Site Map
Home -> Products -> Product Center -> Building Electrical Distribution -> Residual Current Device (RCD/RCCB)
Product Center

A residual current device (RCD), similar to a Residual Current Circuit Breaker (RCCB), is an electrical wiring device that disconnects a circuit whenever it detects that the electric current is not balanced between the energized conductor and the return neutral conductor.

In the United States and Canada, a residual current device is also known as a ground fault circuit interrupter (GFCI), ground fault interrupter (GFI) or an appliance leakage current interrupter (ALCI). In Australia they are sometimes known as "safety switches" or simply "RCD" and in the United Kingdom they can be referred to as "trips" or "trip switches".

Working Principle

The RCCB works on the current balance principle. The supply conductors, i.e., the phases and the neutral, are passed through a torroid and form the primary windings of a current transformer. Its secondary winding is connected to a highly sensitive electromagnetic trip relay, which operates the trip mechanism.

In a healthy circuit, sum of the currents in phases, is equal to the current in the neutral and the vector sum of all currents is equal to zero. If there is any insulation fault in the current and leakage current flows to earth, the currents do not balance and their vector sum is not equal to zero. This imbalance is detected by the core balanced current transformer, the RCCB is tripped and supply to load is interrupted. The trip mechanism is operated at a residual current between 50-100% of its rated tripping current.

Technical information

Pole No.   2 Pole 4 Pole
Standard Conformity   IEC 61008-1 IEC 61008-1
Rated Current (In) A 16, 25, 40, 63 16, 25, 40, 63
Sensitivity (I△n) mA 30, 100, 300, 500 30, 100, 300, 500
Rated Voltage (Un) Vac 240 240 / 415
Rated Insulation Voltage (Ui) V 660 660
Rated Frequency Hz 50 50
Type   A/AC A/AC
Shortcircuit Withstand Capacity kA 6 6
Residual Making Breaking Capacity A 10 In 10 In
Ambient Temperature oC -25 to +40 -25 to +40
Shock Resistance g 20 20
Vibration Resistance g 3 3
Electrical Endurance/Mechanical operations 10000 10000
Mounting Din Rail (35 * 7.5) mm Din Rail (35 * 7.5) mm
Degree of Protection IP 20 IP 20
Terminal Capacity (max) mm2 25 25


Power Semiconductors
Power Supplies
Building Electrical Distribution
Control & Protection
Interface Components
Switches and Switchgears
Industry Electric Appliances
Electric Fittings and Accessories

English German Spanish French Italian Portuguese Korean Arabic Russian
Customer Support: Enquiry | Catalogue Request
About Greegoo | Contact Us | Friendly Link

Copyright 2007 Greegoo All Right Reserved