100x Electrical Safety RCD Test Labels BS7671 (1 Roll) 75x50mm 18th Edition

Product Information

It was therefore agreed that the testing procedure could be greatly simplified and safety would remain unaffected since RCDs are, in any event, tested extensively by manufacturers prior to sale. What are the changes to the requirements for RCD testing? These proposed changes are also reflected in proposed updates to Appendix 7. In addition, the informative Appendix 7 Harmonized cable core colours includes a new item 8: Colour codes for diagrams and specifications, which summarizes (in Table 7F) the BS 7645 colour codes, and recommends that they are used, where required, to identify conductors in operation and maintenance information, such as wiring diagrams and termination schedules. Proposed new Regulation 514.9.2 David Garrett, Product Management Manager at Deta, says “This is a reminder that the regulations affecting consumer units become mandatory on 28th September, and that all designers, developers and installers should be mindful that they need to be compliant from this date. Deta can assist in providing related information and product solutions to match your needs.” Further information on RCD operating and non-operating times can be found in the relevant product standards. Type A and Type AC RCCBs and RCBOs are manufactured to BS EN 61008 and BS EN 61009 respectively, whereas Type F and Type B RCCBs and RCBOs are manufactured to BS EN 62423. Sub Committee A of JPEL/64 scrutinized the product standards for RCDs and noted the complexity of testing parameters, as well as the results permitted by the standards that could be used to prove the functionality of an RCD when bench tested in a laboratory.

that all user instructions, notices and operating and maintenance information comply with the relevant standards for technical documentation (BS EN 61082-1, plus BS EN 81346-1 for certain industrial systems) and user instructions (BS EN IEC/IEEE 82079-1) and This applies to the RCD test label, periodic test label, presence of SPD label (new requirement). The only exception is the warning notice of additional supplies which, if required, will still need to be present on the enclosure. Figure 2 Examples of the label required by proposed Regulation 514.13.1, when the label is not part of an earthing/bonding clamp to BS 951 The note to Regulation 643.8 of BS 7671 which gives the requirements for the verification of an RCD to provide additional protection states that:This is still a consideration for the designer of the installation with Regulation 531.3.2. To achieve this, they should ideally ensure there is no more than 30% of the rated residual operating current due to protective conductor current and/or earth leakage currents (i.e. 9mA for a 30mA device). There is a new indent (ii) to consider the use of RCBOs as opposed to split load arrangements for this purpose.

Many of the issues encountered when testing RCDs are down to user error as opposed to faulty RCDs. It may come as a surprise to some, but RCD testing should be carried out at the RCD with the outgoing wiring disconnected. However, this is not usually done. The usual live working procedures must be considered, and suitable precautions taken when carrying out work near live parts. Residual current protective devices shall be selected and erected such as to limit the risk of unwanted tripping. The following should be considered: an instruction notice, intended to provide information or instructions for users of the installation. The requirements for testing RCDs have been simplified, a single test is all that is required to show compliance with the minimum requirement laid out in BS 7671:2018+A2:2022. Regardless of RCD type, the test is carried out using an alternating test current, applied at the RCD’s rated residual operating current I Δn, the maximum disconnection time is expected to be less than 300ms for a general non-delay type RCD. For S type time-delayed RCDs, the operating time should be 130 - 500 ms. Other kinds of RCD testing may be useful for fault finding purposes. Further information on RCD testing can be found in IET Guidance Note 3 Inspection and Testing and PD IEC TR 62350:2006 Guidance for the correct use of residual current-operated protective devices (RCDs) for household and similar use which states that ‘ The testing current should be applied between the upstream and downstream terminal of the RCD’, see Figure 4 extracted from IET Guidance Note 3 Inspection and Testing.

Cascaded RCDs for selectivity

BS 7671:2018+A2:2022 Requirements for Electrical Installations, IET Wiring Regulations, 18 th Edition.

Similarly, for instruments with a setting for Type B RCDs a multiplier of two times I Δn is applied as required by the product standard, BS EN 62423:2012 Type F and type B residual current operated circuit-breakers with and without integral overcurrent protection for household and similar uses. This is where knowledge of relevant product standards is essential, it would be reasonable to expect a 40 ms maximum disconnection time for a test at five times I Δn as would be the case with an AC test. However, this is not the case as the product standard BS EN 61008 requires a half wave pulsating residual current of 0.35 A (350 mA), see Table 4 extracted from BS EN 61008-1:2012+A2:23-1:2012+A11:2015. There may be some equipment however that would show false readings at this test. It is therefore important that manufacturer’s instructions be consulted and if necessary the equipment disconnected during this 250 V DC test. The early style Residual Current Devices (RCDs) were highly effective protective devices but they have proven to be less reliable in modern buildings as a consequence of DC leakage and DC fault currents caused by electronic equipment. Subsequently, new types of RCD have been developed.

What are the changes to the requirements for RCD testing?

The requirements of Section 443 on protection against transient overvoltages has been completely rewritten with the risk assessment removed.