RCD is a general term used in regulations and codes of practice, including RCCB, RCBO, and CBR. That is, devices that provide residual current “protection”, that is, when the residual current exceeds a defined threshold or the device is manually turned off, they detect the residual current and electrically “isolate” the circuit. Contrary to RCM (Residual Current Monitor) which is used to “detect” residual current but does not provide residual current protection-see the notes to Article 411.1 and the product standards listed at the end of Article 722.531.3.101
RCCB, RCBO, and CBR provide protection by isolating the power supply to prevent residual current faults that cause the equipment to trip or shut down manually.
RCCB (EN6008-1) must be used in combination with a separate OLPD, that is, a fuse and/or MCB must be used to protect it from overcurrent.
RCCB and RCBO have fixed characteristics and are designed to be reset by ordinary people in the event of a fault.
CBR (EN60947-2) Circuit breaker with built-in residual current protection function, suitable for higher current applications >100A.
CBR may have adjustable characteristics and cannot be reset by ordinary people in the event of a fault.
Article 722.531.3.101 also refers to EN62423; additional design requirements applicable to RCCB, RCBO and CBR for detecting F or B residual current.
RDC-DD (IEC62955) stands for residual DC current detection device*; a general term for a series of equipment designed to detect smooth DC fault current in charging applications in Mode 3, and supports the use of Type A or Type F RCDs in the circuit.
The RDC-DD standard IEC 62955 specifies two basic formats, RDC-MD and RDC-PD. Understanding the different formats will ensure that you will not buy products that cannot be used.
RDC-PD (protective device) integrates 6 mA smooth DC detection and 30 mA A or F residual current protection in the same device. The RDC-PD contact is electrically isolated in the event of a residual current fault.