Metal Fuse Switch 4 Pole 125A with 3 Pole Fuseholder (WFMS/3P)
18th Ed. Compliant
2-Year Warranty
UK Stock
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The WFMS/3P is a 125 A metal fuse switch assembly combining a 4-pole main switch with a 3-pole 22 × 58 mm fuseholder for robust three-phase circuit isolation and protection. It’s built for commercial and industrial distribution where compliance, accessibility, and reliable disconnection under load are essential. Installer Tip: Use...
The WFMS/3P is a 125 A metal fuse switch assembly combining a 4-pole main switch with a 3-pole 22 × 58 mm fuseholder for robust three-phase circuit isolation and protection. It’s built for commercial and industrial distribution where compliance, accessibility, and reliable disconnection under load are essential.
Installer Tip: Use the WFMS/3P as the main fused incomer for small three-phase boards, HVAC systems, or EV charging pillars. The fourth neutral pole ensures full isolation, while the 22 × 58 fuse links provide phase-selective protection in accordance with BS 7671 Reg 537.2.
- 125 A 4-pole switch-fuse assembly (3-phase + neutral isolation)
- Three 22 × 58 fuseholders – accepts 63 A – 125 A cartridges
- Industrial-grade steel enclosure with secure screw-fix lid
- Front-operated isolator handle for safe disconnection under load
- Complies with BS EN 60947-3 for switch-disconnector-fuse units
- Compatible with Type 2 SPDs and standard NH fuse links
Model | Main Switch | Fuses | Poles | Common Use |
---|---|---|---|---|
WFMS100 | 100 A 2 Pole | 1 × 22 × 58 | Single Phase | Domestic mains isolation |
WFMS100/3F | 100 A 2 Pole | 3 × 22 × 58 | Single Phase | Fused incomer with cartridges |
WFMS/3P | 125 A 4 Pole | 3 × 22 × 58 | Three Phase + N | Commercial & industrial boards |
WFMSRT00-3F | 125 A 4 Pole | 3 × 22 × 58 | Three Phase + N | Sub-main with time-delay RCD |
Engineered for durability and compliance, the WFMS/3P integrates cleanly into new or retrofit three-phase panels, providing safe isolation and phase protection with a compact footprint and installer-friendly layout.
Is the WFMS/3P suitable for balanced three-phase loads?
Yes – it provides fused protection on all three live conductors with a switched neutral for full isolation.
Can I use this upstream of an EV or solar distribution board?
Yes – it’s ideal as a main fused isolator for EV-ready consumer units or three-phase solar systems.
Does it include fuses?
No – fuses are specified separately (63 A – 125 A). We stock compatible 22 × 58 cartridge links for this unit.
Is a neutral pole necessary?
Yes – the 4-pole switch isolates neutral as required by BS 7671 Reg 537.2.2.1 for safe disconnection of all conductors.
Can this be wall-mounted outdoors?
No – the enclosure is IP40 rated and designed for indoor plant rooms or meter areas. For external use, house within an IP65 weatherproof enclosu
- Model: WFMS/3P
- Main Switch Rating: 125 A 4 Pole (AC-22 A duty)
- Fuse Holder Type: 3 × 22 × 58 cartridge holders
- Fuse Range: 63 A – 125 A cartridges
- Enclosure Type: Metal-clad, surface mount, powder-coated steel
- Dimensions (W × H × D): 240 × 160 × 112 mm
- Ingress Protection: IP40 (indoor use)
- Voltage Rating: 400 V AC / 50 Hz
- Operating Temperature: -20 °C to +50 °C
- Compliance: BS EN 60947-3 / BS 7671 Amendment 2
Supplied pre-assembled with a 125 A 4-pole main switch and 3-pole fuseholder. Install by a qualified electrician familiar with three-phase wiring and fault-level coordination.
- Mount on a rigid, non-combustible surface
- Use suitable glands on side or bottom knockouts
- Fit 22 × 58 fuses rated for load current and cable size
- Verify phase rotation and neutral continuity before energising
- Ensure enclosure bonding per BS 7671 Reg 411.3.1.1