CENELEC - EN 61008-1
Residual current operated circuit-breakers without integral overcurrent protection for household and similar uses (RCCB's) Part 1: General rules
Organization: | CENELEC |
Publication Date: | 1 September 2004 |
Status: | inactive |
Page Count: | 142 |
ICS Code (Fuses and other overcurrent protection devices): | 29.120.50 |
scope:
This International Standard applies to residual current operated circuit-breakers functionally independent of, or functionally dependent on, line voltage, for household and similar uses, not incorporating overcurrent protection (hereafter referred to as RCCBs), for rated voltages not exceeding 440 V a.c. and rated currents not exceeding 125 A for fixed installations, intended principally for protection against shock-hazard.
These devices are intended to protect persons against indirect contact, the exposed conductive parts of the installation being connected to an appropriate earth electrode. They may be used to provide protection against fire hazards due to a persistent earth fault current, without the operation of the overcurrent protective device.
RCCBs having a rated residual operating current not exceeding 30 mA are also used as a means for additional protection in case of failure of the protective means against electric shock.
This standard applies to devices performing simultaneously the functions of detection of the residual current, of comparison of the value of this current with the residual operating value and of opening of the protected circuit when the residual current exceeds this value.
NOTE 1 The requirements for RCCBs are in line with the general requirements of IEC 60755. RCCBs are essentially intended to be operated by uninstructed persons and designed not to require maintenance. They may be submitted for certification purposes.
NOTE 2 Installation and application rules of RCCBs are given in IEC 60364.
RCCBs within the scope of this standard are intended for used in an environment pollution degree 2. They are suitable for isolation.
Devices to this standard are suitable for use in IT systems if the requirements of the installation rules are met.
Special precautions (e.g. lightning arresters) may be necessary when excessive overvoltages are likely to occur on the supply side (for example in the case of supply through overhead lines) (see IEC 60364-4-443).
RCCBs of the general type are resistant to unwanted tripping including the case where surge voltages (as a result of switching transients or induced by lightning) cause loading currents in the installation without occurrence of flashover. RCCBs of the S type are considered to be sufficient proof against unwanted tripping even if the surge voltage causes a flashover and a follow-on current occurs.
NOTE 3 Surge arresters installed downstream of the general type of RCCBs and connected in common mode may cause unwanted tripping.
NOTE 4 For RCCBs having a degree of protection higher than IP20 special constructions may be required.
Particular requirements are necessary for
- Residual current operated circuit-breakers with integral overcurrent protection (see IEC 61009);
- RCCBs integrated in one unit with a socket-outlet or designed exclusively for being associated locally with a socket-outlet in the same mounting box.
NOTE 5 Until a specific EN for SRCDs is prepared and approved, for RCCBs integrated in one unit with a socket-outlet or designed exclusively for being associated locally with a socket-outlet in the same mounting box the requirements of this standard in conjunction with those of IEC 60884-1 may be used as far as applicable
The requirements of this standard apply for normal environmental conditions (see 7.1). Additional requirements may be necessary for RCCBs used in locations having severe environmental conditions.
RCCBs including batteries are not covered by this standard.
This standard contains all requirements necessary to ensure compliance with the operational characteristics required for these devices by type tests.
It also contains the details relative to test requirements and methods of testing necessary to ensure reproducibility of test results.
This standard states
a) the characteristics of RCCBs,
b) the conditions with which RCCBs shall comply, with reference to
1) their operation and behaviour in normal service,
2) their operation and behaviour in case of short-circuits,
3) their operation under residual current conditions,
4) their dielectric properties,
5) EMC,
c) the tests intended for confirming that these conditions have been met and the methods to be adopted for the tests,
d) the data to be marked on the devices,
e) the test sequences to be carried out and the number of samples to be submitted for certification purposes (see Annex A),
f) the routine tests to be carried out on each RCCB to reveal unacceptable variations in material or manufacture, likely to affect safety (see Annex D).