Fused Main Switch - WFIS100
The WFIS100 is a compact, insulated fused main switch rated at 100A AC21 - designed for safe isolation and protection of incoming supplies. Supplied with both 80A and 100A general-purpose fuses, this unit is ideal for consumer unit upgrades, EV installs, and sub-main distribution boards. Constructed from non-combustible Bakelite and...
The WFIS100 is a compact, insulated fused main switch rated at 100A AC21 - designed for safe isolation and protection of incoming supplies. Supplied with both 80A and 100A general-purpose fuses, this unit is ideal for consumer unit upgrades, EV installs, and sub-main distribution boards.
Constructed from non-combustible Bakelite and fitted with a cable shroud, it provides durable and reliable protection in residential, commercial, and light industrial environments. The fuse carrier can only be removed in the OFF position, adding a vital layer of safety during maintenance or fuse replacement.
- Rated at 100A AC21 – incoming supply protection
- Includes both 80A and 100A fuses (general purpose)
- Made from non-combustible Bakelite for high safety
- Cable entry capacity: 35mm x 35mm max
- Fuse removal lockout: only in OFF position
Commonly used for isolating meter tails, sub-boards, and dedicated EV or solar feeds where fused protection is required upstream.
What’s the difference between this and a standard main switch?
This unit includes fuses for built-in circuit protection, whereas a standard main switch only provides isolation. It’s ideal where both are required in one device.
Can I use this before a consumer unit?
Yes – it’s commonly installed upstream of a board or alongside meter tails to provide safe isolation and overcurrent protection.
What fuse ratings are included?
Both 80A and 100A fuses are supplied, giving flexibility depending on your system requirements.
- Product Code: WFIS100
- Rated Current: 100A / AC21
- Fuses Supplied: 80A and 100A (general purpose)
- Construction: Non-combustible Bakelite body
- Cable Capacity: Up to 35mm x 35mm
- Safety Feature: Fuse carrier removable only in OFF position
- Standard: BS EN 60497-3
- Dimensions: 52mm (W) x 79mm (H) x 126mm (D)
Install the WFIS100 at the head of a circuit or distribution point where fused isolation is required. Always ensure the unit is switched OFF before removing the fuse carrier. Suitable for use between meter tails and consumer units, or before surge protection modules.
- Surface mount using rear fixings
- Use heat-rated 80A/100A fuse depending on system spec
- Maintain clear access for fuse replacement
- Seal after installation if required by DNO or regulations
