Metal Fuse Switch - WFMS
The WFMS Metal Fuse Switch range provides a compact, compliant, and high-integrity solution for fused mains isolation across single-phase and three-phase installs. Built with robust enclosures and 22×58 fuse holders, each variant is designed to meet different site needs - from basic protection to integrated surge compliance or time-delayed RCD...
The WFMS Metal Fuse Switch range provides a compact, compliant, and high-integrity solution for fused mains isolation across single-phase and three-phase installs. Built with robust enclosures and 22×58 fuse holders, each variant is designed to meet different site needs - from basic protection to integrated surge compliance or time-delayed RCD functionality.
All units come pre-fitted with a 100A or 125A main switch, with variants offering fuses, SPD protection, or time-delayed RCDs depending on the SKU. Suitable for domestic mains upgrades, commercial boards, or light industrial installs.
Available Variants:
- WFMS100: 100A Main Switch + 22×58 Fuse Holder (no fuses)
- WFMS100/3F: As above, supplied with 3 fuses – 63A, 80A, and 100A
- WFMS100/3FSP: Includes 3 fuses and built-in Surge Protection Device
- WFMS/3P: 125A 4 Pole Main Switch + 3 Pole 125A Fuse Holder (Three Phase)
- WFMSRT00/3F: Fused Main Switch + Time Delayed RCD + 3 Fuses
Key features across the range include:
- 100A or 125A switch-rated metal fuse enclosure
- Compact DIN-compliant footprint - fits most consumer unit backplates
- 22x58 fuse holders - pre-fitted or supplied loose depending on model
- Three-phase, SPD, and time-delayed RCD variants available
- Pre-drilled knockouts and secure steel casing for install-ready reliability
What’s the difference between WFMS100 and WFMS100/3F?
WFMS100 includes the metal enclosure, 100A switch, and fuse holder — but no fuses. WFMS100/3F includes three fuse cartridges (63A, 80A, and 100A) to suit your site’s spec.
Does the WFMS100/3FSP include surge protection?
Yes – it comes pre-fitted with a Type 2 SPD module for mains surge protection, making it suitable for 18th Edition compliance where surge risk is present.
Is the WFMS/3P suitable for three-phase installs?
Yes – this variant includes a 4-pole 125A main switch and a 3-pole fuse holder, designed specifically for three-phase commercial or light industrial use.
What’s the purpose of the Time-Delayed RCD variant?
The WFMSRT00/3F includes a time-delayed RCD, offering discrimination from downstream RCDs - often required in sub-main setups or critical equipment protection.
Can I install this in a domestic property?
Yes - several variants (e.g. WFMS100/3F or WFMS100/3FSP) are commonly used for domestic incomers, EV installs, or garage sub-boards requiring fused protection.
- Enclosure Type: Metal-clad, surface-mount
- Main Switch Rating: 100A or 125A (variant-dependent)
- Fuse Holder Type: 22×58 cartridge holder
- Fuses Supplied: 63A, 80A, 100A (included in /3F, /3FSP, RT00 variants)
- SPD: Included in WFMS100/3FSP only
- Time-Delayed RCD: Included in WFMSRT00/3F
- Poles: 2P or 4P (WFMS/3P = 4P switch + 3P fuseholder)
- Dimensions (W x H x D mm):
- WFMS100 / 100/3F / RT00/3F: 130 x 238 x 87
- WFMS100/3FSP: 160 x 240 x 112
- WFMS/3P: 240 x 160 x 112
- Standards: Conforms to IEC 60947
This range is designed for fast install into new or existing distribution systems. Units come fully assembled, and fused variants are supplied with loose or pre-installed cartridges. Final wiring must be completed by a qualified electrician.
- Knockouts on rear and sides for adaptable cable entry
- Mount securely to a suitable surface and ensure full enclosure bonding
- SPD earth path should be as short and direct as possible
- For three-phase installs (WFMS/3P), ensure correct fuse polarity per phase
- Test RCD (if included) prior to energising circuit
