400/415 Volt Electricity Supply Distribution Fuse-Links to IEC 60269-2/BS 88-2 – Type J

400/415V Electricity Supply Distribution Fuse-Links to IEC 60269-2 / BS 88-2 – Type J 

J Type Fuse | Wedge Type Fuse | Distribution Fuse | 82mm Fuse | 92mm Fuse

Product Introduction

The Lawson Type J is the definitive J Type Fuse range for use in UK ,MEA and Africa a.c. electricity supply networks. As a certified Wedge Type Fuse with wedge contact connections, the Type J Distribution Fuse is the standard fuse-link used throughout the UK,MEA and Africa electricity distribution infrastructure — installed in distribution boards, feeder pillars, link boxes, pole-mounted cut-outs, and heavy-duty service intakes serving commercial, industrial, and residential properties.

Available in both 82mm Fuse (JPU series, 82mm fixing centres) and 92mm Fuse (JSU series, 92mm fixing centres) formats, as well as in a 76mm fixing centre variant (JHU series) and a cylindrical format (JF series), the Lawson Type J Distribution Fuse covers every current rating specified in BS 88-2 and BS 7656 — from 20A through to 800A — together with additional non-standardised ratings to meet specific network requirements. With a breaking capacity of 80kA at 415V a.c., the Type J Wedge Type Fuse is rated for the highest fault levels encountered on the UK ,MEA and Africa  LV distribution network.

Key Features

• J Type Fuse — the standard fuse-link for UK ,MEA and Africa electricity supply distribution networks
• Wedge Type Fuse with wedge contact connections — secure, low-resistance contact design for long-service reliability
• Distribution Fuse rated at 415V a.c. — for three-phase 400/415V electricity supply applications
• Breaking capacity: 80kA at 415V a.c. — rated for the highest fault levels on UK LV distribution networks
• Utilisation category gG — full-range overload and short-circuit protection
• 82mm Fuse (JPU series) — standard 82mm (3¼ inch) fixing centres, rated 20A to 630A
• 92mm Fuse (JSU series) — standard 92mm (3⅝ inch) fixing centres, rated 20A to 800A
• 76mm Fuse (JHU series) — non-standard 76mm (3 inch) fixing centres, rated 20A to 315A
• Cylindrical format (JF series) — 47mm x 40mm, rated 20A to 315A
• Female contact fuse-links also available
• Covers all current ratings specified in BS 88-2 and BS 7656
• Additional non-standardised current ratings available
• Compliant with IEC 60269-2 / BS 88-2 — internationally recognised distribution fuse standard
• Compatible with Lawson Type FH fuse carriers (FH 82 and FH 92)

Understanding the Type J Fuse Series

JPU Series — 82mm Fuse (82mm / 3¼ inch fixing centres) The JPU series is the most widely specified 82mm Fuse in UK electricity distribution, used in the vast majority of standard distribution boards, feeder pillars, and service intake equipment with 82mm fixing centre bases. Available from 20A to 630A, the JPU J Type Fuse covers virtually all standard LV distribution circuit ratings within the UK ,MEA and Africa electricity supply network.

JSU Series — 92mm Fuse (92mm / 3⅝ inch fixing centres) The JSU series 92mm Fuse is used in higher-current distribution applications and in equipment with 92mm fixing centre bases, available from 20A up to 800A. The JSU 800A extends beyond the standard range specified in IEC 60269-2 and BS 88-2, providing a Distribution Fuse solution for the largest LV supply points on the network where conventional rated fuse-links would be undersized.

JHU Series — 76mm Fuse (76mm / 3 inch fixing centres) The JHU series provides a Wedge Type Fuse for non-standard 76mm fixing centre bases, available in ratings from 20A to 315A. This series is used for replacement and maintenance purposes in older network equipment with the earlier 76mm fixing centre dimension.

JF Series — Cylindrical Format (47mm x 40mm) The JF cylindrical series offers an alternative Distribution Fuse format for specific equipment types, available in ratings from 20A to 315A.

Applications

The Lawson Type J J Type Fuse, Wedge Type Fuse, and Distribution Fuse range is specified across the full scope of UK ,MEA and Africa electricity supply distribution infrastructure:

• LV distribution boards — main low-voltage distribution boards in substations and switching stations
• Feeder pillars — street-mounted LV electricity distribution equipment serving residential and commercial areas
• Link boxes — underground cable network LV link boxes and jointing chambers
• Pole-mounted cut-outs — overhead line distribution cut-out equipment on rural and suburban distribution networks
• Heavy-duty service intakes — large commercial, industrial, and multi-occupancy residential service connections
• Primary distribution centres — high-current main incoming supply fusing at primary distribution points
• Fused distribution cabinets — Lucy Electric and other DNO distribution cabinet equipment
• New connections and network reinforcements — new LV service fusing for DNO and ICP work

Why Choose Lawson Type J Distribution Fuse?

Lawson Type J fuse-links are for use in a.c. electricity supply networks, installed in distribution boards, feeder pillars, link boxes, pole mounted cut-outs and heavy duty service intakes. Lawson Fuses For over 80 years, Lawson Fuses has been a trusted manufacturer and supplier to UK electricity distribution network operators, DNOs, and their approved contractors. The Type J J Type Fuse and Wedge Type Fuse range is designed and tested as a complete system with the Lawson Type FH fuse carriers — ensuring that every 82mm Fuse, 92mm Fuse, and cylindrical Distribution Fuse meets the performance requirements of IEC 60269-2 and BS 88-2 as a coordinated, certified protection system.

With current ratings from 20A to 800A, four fixing centre options, and a 80kA breaking capacity at 415V a.c., the Lawson Type J offers the most comprehensive J Type Fuse range available from a UK manufacturer. All products are ASTA Certified, manufactured under an ISO 9001 accredited quality management system, with test facilities independently accredited to ISO/IEC 17025.

Q1. What is a J Type Fuse?

A J Type Fuse is a wedge-contact electricity supply distribution fuse-link designed for use in UK a.c. electricity supply networks at 400/415V. Lawson Type J fuse-links are installed in LV distribution boards, feeder pillars, link boxes, pole-mounted cut-outs, and heavy-duty service intakes throughout the UK distribution network. The Type J is available in four formats — the JPU (82mm Fuse), JSU (92mm Fuse), JHU (76mm), and JF (cylindrical) — covering current ratings from 20A to 800A with an 80kA breaking capacity at 415V a.c.

Q2. What is a Wedge Type Fuse?

A Wedge Type Fuse is a fuse-link that uses wedge-shaped contacts to create a secure, low-resistance mechanical and electrical connection when inserted into a fuse carrier. The wedge contact design draws the contact surfaces firmly together under spring or mechanical pressure, maintaining a reliable, stable connection throughout the service life of the fuse. The Lawson Type J is a Wedge Type Fuse specifically designed for use in UK electricity supply distribution equipment with standard 76mm, 82mm, and 92mm fixing centre bases.

Q3. What is a Distribution Fuse?

A Distribution Fuse is a high-current fuse-link used within electricity supply distribution networks to protect LV distribution circuits, cables, and service connections from overload and short-circuit faults. The Lawson Type J Distribution Fuse is rated at 415V a.c. with an 80kA breaking capacity and covers the full range of current ratings from 20A to 800A required for UK LV distribution applications. It is the standard Distribution Fuse specified by UK Distribution Network Operators (DNOs) and Independent Connection Providers (ICPs) for LV network fusing.

Q4. What is the difference between an 82mm Fuse (JPU) and a 92mm Fuse (JSU)?

The 82mm and 92mm designations refer to the fixing centres — the distance between the two contact fixing points — of the J Type Fuse. The 82mm Fuse (JPU series) has 82mm (3¼ inch) fixing centres and is rated up to 630A, used in standard distribution equipment with 82mm bases. The 92mm Fuse (JSU series) has 92mm (3⅝ inch) fixing centres and is rated up to 800A, used in higher-current applications and in distribution equipment with 92mm bases. The fixing centre must match the fuse carrier and base in the installation — the two sizes are not interchangeable.

Q5. What is the current range available for the Type J J Type Fuse?

The full Lawson Type J Distribution Fuse range covers ratings from 20A to 800A across the four series. The JPU (82mm Fuse) covers 20A–630A. The JSU (92mm Fuse) covers 20A–800A. The JHU (76mm) covers 20A–315A. The JF cylindrical covers 20A–315A. Additional non-standardised current ratings are also available — contact the Lawson Fuses sales team for details.

Q6. What breaking capacity does the Lawson Type J Distribution Fuse have?

The Lawson Type J J Type Fuse has a breaking capacity of 80kA at 415V a.c. — tested and certified in compliance with IEC 60269-2 and BS 88-2. This is sufficient to safely interrupt the maximum prospective fault currents likely to be encountered at LV distribution points on the UK electricity supply network.

Q7. What standards does the Type J Wedge Type Fuse comply with?

The Lawson Type J Distribution Fuse complies with IEC 60269-2 and BS 88-2 (the international and British Standards for low-voltage fuse-links for industrial and electricity supply applications), as well as BS 7656 which specifies the additional current ratings and performance requirements for UK electricity supply distribution fuse-links. All products are ASTA Certified under the ASTA 20 Authorisation Scheme.

Q8. Where is the J Type Fuse installed?

The Lawson Type J J Type Fuse is installed throughout the UK LV electricity distribution network in distribution boards, feeder pillars, link boxes, pole-mounted cut-outs on overhead distribution lines, and heavy-duty service intakes for large commercial and industrial premises. It is specified and used by UK Distribution Network Operators (DNOs), Independent Connection Providers (ICPs), local authorities, and approved electrical contractors carrying out work on the LV electricity supply network.

Q9. Are there any restrictions on the use of JPU 450–630A and JSU 800A fuse-links?

Yes. The JPU 450A, 500A, 560A, and 630A 82mm Fuse variants are restricted to intermittent loading when installed in 400A fixed contacts. The JSU 800A 92mm Fuse is restricted to intermittent loading when installed in 630A fixed contacts. The JSU 800A also extends beyond the current ratings covered by IEC 60269-2 and BS 88-2 (which specify performance requirements up to 630A fixed contacts), though its performance complies with the Breaking Range and Utilisation Category gG. Always refer to the product information sheet and relevant network specifications before selecting these extended ratings.

Q10. What fuse carriers are compatible with the Lawson Type J Distribution Fuse?

The Lawson Type J J Type Fuse is designed for use with the Lawson Type FH fuse carriers — the FH 82 for JPU series 82mm Fuse links (up to 400A) and the FH 92 for JSU series 92mm Fuse links (up to 630A). These wedge-type fuse carriers are tested and certified as a complete system with the Type J fuse-links to IEC 60269-2 and BS 88-2.

Q11. How do I order the Lawson Type J J Type Fuse or Distribution Fuse?

The full Lawson Type J Wedge Type Fuse, 82mm Fuse, 92mm Fuse, and Distribution Fuse range is available through the Lawson Fuses sales team and their network of authorised sales partners and electrical wholesalers across the UK. Contact Lawson Fuses directly for trade pricing, availability by current rating and fixing centre, and technical support for your electricity distribution installation or network maintenance project.