BS 7671:2018+A4:2026 Inspection & Testing Updates Explained

With the official release of BS 7671:2018+A4:2026, electrical inspectors and contractors must adapt to updated requirements in Part 6 (Inspection and Testing), revised certificate schedules, and enhanced requirements for energy storage and EV charging installations.

Here is a summary of the critical changes every City & Guilds 2391 candidate and qualified supervisor needs to know.

Key Changes in Part 6 & Appendix 6

1. Minor Electrical Installation Works Certificate Exclusions

Under revised Regulation 644.4.201, the scope of a Minor Works certificate (MEIWC) has been clarified:

• Distribution Board Replacements: Must be recorded on a full Electrical Installation Certificate (EIC) with complete schedules of inspection and test results. An MEIWC is explicitly prohibited for board replacements.
• New Circuits: Any work introducing a new circuit at the consumer unit requires a full EIC.

2. Enhanced RCD Testing Standards

Amendment 4 aligns RCD verification with modern Type A, Type F, and Type B residual current devices:

• Testing at $1\times I_{\Delta n}$ residual current remains mandatory for all safety RCDs.
• Manual test button verification must be confirmed and recorded on all EIC and EICR schedules.

3. Functional & Earth Electrode Verification

For installations incorporating prosumer low-voltage electrical installations (PEI) such as battery storage systems and bidirectional EV chargers:

• Neutral-earth bonding switches must undergo functional verification during initial inspection.
• Earth electrode resistance testing ($R_A$) procedures are mandated for islanded mode operating regimes.

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Stay Ahead of the 2391-52 Standards

Practice updated exam questions reflecting BS 7671:2018+A4:2026 with our 2391 Exam Topics, test circuit parameters with our BS 7671 Electrical Calculators, and review our recommended IET books and testing gear.