On-Site Guide (BS 7671:2018+A2:2022) (Electrical Regulations)

Product Information

Individual PEIs are considered to be an electrical installation (for example, a private house or workshop) that can either produce or consume electrical energy. Three operating modes are considered for individual PEIs. These are: writing of the publishers, or in the case of reprographic reproduction in accordance with the terms of BSI is the business improvement and standards company that enables organizations to turn standards of best practice into habits of excellence, ‘inspiring trust for a more resilient world’. BS 7671:2018+A2:2022 Requirements for Electrical Installations, IET Wiring Regulations 18th Edition (inc. changes from first amendment, published Feb 2022)

The impact of Amendment 2 of the 18th edition (BS 7671:2018 The impact of Amendment 2 of the 18th edition (BS 7671:2018

Amendment 2 comes into effect immediately when published on 28th March 2022 and the previous version, BS 7671:2018+A1:2020, will be withdrawn six months later. BS EN 62423:2012+A11:2021 Type F and type B residual current operated circuit-breakers with and without integral overcurrent protection for household and similar uses.Regulation 443.4 for determining if protection against transient overvoltages is needed has been redrafted. For further information on the different RCD Types and the selection process, see IET Wiring Matters article (Issue 77 September 2019), ‘Which RCD Type?’

NICEIC | Site Guide 100 A

Given that an RCD may take up to 0.3 seconds (300 ms) to disconnect it would appear at first glance that some disconnection times in Table 41.1 may not be achievable, for example, the maximum disconnection time for some final circuits on a TT earthing system is 0.2 seconds (200 ms), as shown in Table 3. However, a note under the table indicates that earth faults are of negligible impedance and it follows that disconnection times would be commensurately higher since a value of, for example, a residual current of 60 mA would be expected to provide a disconnection time of 150 ms and 40 ms (0.04 seconds) for a residual current of 150 mA, as shown in Table 2. Therefore, an operating time of 300 ms would be considered acceptable for a TT earthing system. Regulation 422.1 (Precautions where particular risks of fire exist. General) now introduces requirements for the fire safety design of the building(s) to be documented. Regulation 422.2 (Conditions for evacuation in an emergency) introduces separate requirements for escape routes and a new concept of ‘protected escape routes’. Reference to conditions BD2, BD3, and BD4 have been deleted. Chapter 44 Protection against voltage disturbances and electromagnetic disturbances The days of selecting an RCD according to current rating and rated residual current alone are gone, now the designer must select the RCD according to the nature of the residual fault currents, including pulsed or steady-state DC components expected to be present.

Specification

BS EN IEC 61557-6:2021 Electrical safety in low voltage distribution systems up to 1 000 V a.c. and 1 500 V d.c. Equipment for testing, measuring or monitoring of protective measures. Effectiveness of residual current devices (RCD) in TT, TN and IT system. The requirements for RCD testing in BS 7671:2018+A2:2022 are given in the notes to Regulation 643.7.1 for fault protection and Regulation 643.8 for additional protection. A note in each section states the requirements and the key points are highlighted below. The Amendment continues the thread of embracing new technologies and Prosumer’s Low Voltage Electrical Installations is an exciting step into the future of renewable sources of energy and their integration into our lives. The result is BS 7671:2018+A2:2022 - a modern standard that improves fire and end-user safety and increases sustainability. The previous version of this standard - BS 7671:2018+A1:2020 - is being withdrawn on 27 September 2022. All electrical installations must comply with BS 7671:2018+A2:2022 from 28 September 2022. It is essential to understand the limitations of the test instrument and product standard requirements when testing RCDs using the available RCD Type settings on the test instrument.