The On-Site Guide from the Institution of Engineering & Technology is an essential, updated reference for competent installers working with electrical installations up to 100 A, 3-phase. This spiral-bound guide incorporates the extensive changes to BS 7671, ensuring you stay current with the latest regulations.

• Essential guide to BS 7671, incorporating all four amendments to the 18th Edition.
• Aligns directly with BS 7671:2018+A4:2026 The IET Wiring Regulations.
• Provides convenient, easy-to-use essential information for competent installers.
• Includes new topics such as bidirectional and unidirectional protective devices.
• Features guidance on Stationary Secondary Batteries and selection of RCDs.
• Contains amended rationale for maximum Zs values for protective devices.
• Includes guidance on prospective fault current for protective devices.

• Edition: 9th Edition
• Binding: Spiral Bound
• Language: English
• Pages: 256 pages
• ISBN 10: 1837240396
• ISBN 13: 978-1837240395
• Dimensions: 148x51x210mm (or 14.8 x 5.08 x 21 cm)
• Weight: 490g
• Publication Date: June 10, 2026
• Series: Part of Electrical Regulations series

This 9th Edition On-Site Guide is vital for maintaining compliance and effectively managing electrical installations within the specified parameters.