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Residual Current Devices
used in Consumer Units
RCD - Residual Current Device
A generic term for devices providing earth fault protection.
RCBO - Residual Current Operated Circuit-Breaker with
Integral Overcurrent Protection
A mechanical switching device designed to make, carry and break currents
under normal service conditions and to cause the opening of the contacts
when the residual current attains a given value under specified conditions.
In addition it is designed to give protection against overloads and/or short
circuits and can be used independently of any other overcurrent protective
device within its rated short circuit capacity.
RCCB - Residual Current Operated Circuit-Breaker
without Integral Overcurrent Protection
A mechanical switching device designed to make, carry and break currents
under normal service conditions and to cause the opening of the contacts
when the residual current attains a given value under specified conditions.
It is not designed to give protection against overloads and/or short circuits
and must always be used in conjunction with an overcurrent protective
device such as a fuse or circuit-breaker.
Consumer Unit
MCB
RCBO
RCCB
Guide to
| 17th Edition Consumer Units
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