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The Wiska Combi 304 series proves that small can still be mighty. Designed for tight corners, soffits, meter cupboards, and discrete outdoor terminations, the 304 retains robust IP66 performance without the bulk of larger boxes. If space is limited but compliance and durability still matter, the Combi 304 is a reliable, installer‑friendly choice.
Wiska Combi 304 Features at a Glance
- Compact footprint that hides neatly on façades and under eaves.
- IP66 protection against dust and powerful water jets.
- Well‑placed knockouts with soft membranes for quick, clean entries.
- Optional lids: integrated LED for service lighting, or rotary switch for local isolation.
BS 7671: Staying Compliant in Small Spaces
- Reg. 522.8.1/522.3.2 – Environmental and mechanical protection: size the gland to the cable O.D. and avoid back drilling that compromises IP.
- Reg. 526.3/526.5 – Make connections accessible and durable; keep test access in mind even when space is tight.
- Reg. 134.1.1 – Good workmanship: matched components (enclosure, glands, connectors) are part of compliance.
Installer Tips (and a Common Misconception)
Unlike larger Combi models (e.g., 407/607), Combi 304 does not use the deeper slot‑style fixings. Instead, use the designated mounting holes and maintain gasket integrity. Inside the box, compact connectors keep things simple:
- Use Wago 221 or Ideal push‑ins for quick, tidy wiring.
- Route SWA outdoor‑rated cable through correctly sized glands to preserve IP66.
- Where required, maintain bonding with appropriate earthing accessories.
Creative Add‑Ons: Rotary Switch and LED Lids
The rotary‑switch lid transforms the 304 into a compact isolation point for pumps, signage, or outdoor luminaires. The LED lid turns the enclosure itself into a small task light — useful in meter cupboards, service voids, and soffits. Both accessories reduce box count and speed installation while maintaining enclosure integrity.
Case Study: Compact Soffit Wiring Hub
An installer replacing time‑worn junctions selected Combi 304 to hide behind a gutter drop. With glands sized to cable O.D. and Wago 221 inside, testing was straightforward and the lid sealed cleanly. After a season of storms, an inspection found no ingress tracks — proof that small enclosures can perform when installed correctly.
FAQs – Combi 304
Can I bury a 304?
No. Use IP68 resin joint kits for underground connections.
Will Wago 221 fit comfortably?
Yes — choose appropriate sizes and keep conductor lengths tidy.
Does the LED lid affect IP rating?
It’s designed to maintain the enclosure’s integrity when fitted as instructed.
Is 304 big enough for SWA terminations?
Usually not ideal; step up to a larger Combi and use brass glands.
Silly but useful: Can I colour‑match the box with spray paint?
Yes, but keep paint off the gasket and threads.
About Wiska
Wiska’s knack for compact problem‑solving shows in the 304. Rather than shrinking a big box, the team rethought internal volume, lid geometry, and accessory options — helping electricians deliver discreet, compliant junctions that still welcome a tester’s probes.
Why Buy from Electrical4Less
We carry strong stock of Wiska Combi 304, accessory lids, glands, and venting. As a family‑run wholesaler and EDA member, we prioritise fast next‑day delivery, pragmatic advice, and trade‑friendly pricing that keeps your schedule intact.
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References
- https://www.electrical4less.co.uk/product-category/wiska-shop/
- https://www.electrical4less.co.uk/product-category/wago-221/
- https://www.electrical4less.co.uk/product-category/ideal-connectors/
- https://www.electrical4less.co.uk/product-category/earthing/
Wiska Combi 304 Series Explained – Compact Junction Boxes