20A 4 Pole 10kA MCB B Curve – WKC420B
18th Ed. Compliant
2-Year Warranty
UK Stock
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The WKC420B is a 20A 4 pole 10kA Miniature Circuit Breaker (MCB) designed for three-phase + neutral protection. With its B Curve trip characteristic, it is best suited for resistive loads such as small power circuits, lighting systems, and distribution boards in three-phase networks, EV charger boards, and solar PV...
The WKC420B is a 20A 4 pole 10kA Miniature Circuit Breaker (MCB) designed for three-phase + neutral protection. With its B Curve trip characteristic, it is best suited for resistive loads such as small power circuits, lighting systems, and distribution boards in three-phase networks, EV charger boards, and solar PV installs.
Offering a 10kA breaking capacity, the WKC420B provides reliable overload and short-circuit protection while isolating all live conductors and neutral. It is bi-directional, DIN-rail mounted, and manufactured to BS 7671 (18th Edition) standards.
Installer Tip: Choose the 20A B Curve when you need to protect small to medium resistive loads. Always confirm fault current capacity of the board does not exceed 10kA before selection.
Key Features
- 20A 4 Pole MCB – B Curve trip characteristic
- 10kA breaking capacity – suitable for commercial installs
- Four-pole protection – L1, L2, L3 + Neutral
- Bi-directional feed – top or bottom entry
- DIN-rail mounted – 18mm per module
- Complies with BS 7671 (18th Edition)
Compare WKC 4 Pole 10kA MCBs (B Curve)
| Model | Rating | Curve | Breaking Capacity |
|---|---|---|---|
| WKC416B | 16A | B Curve | 10kA |
| WKC420B (This Product) | 20A | B Curve | 10kA |
| WKC425B | 25A | B Curve | 10kA |
| WKC432B | 32A | B Curve | 10kA |
What applications is the WKC420B suited for?
It is best for resistive load circuits such as lighting, small appliances, and socket sub-circuits.
What’s the benefit of a 4-pole breaker over 3-pole?
It isolates and protects the neutral conductor as well as all three live phases, essential for three-phase + N installs.
Can this MCB be used in EV charger setups?
Yes, provided the circuit is resistive and the board fault level is within 10kA. For inductive loads, use a C curve variant.
Is this compliant with UK regulations?
Yes, it meets BS 7671 (18th Edition) and IEC/EN 60898-1.
- Model: WKC420B
- Type: Miniature Circuit Breaker (MCB)
- Current Rating: 20A
- Curve: B Curve
- Poles: 4P (L1, L2, L3 + Neutral)
- Breaking Capacity: 10kA
- Mounting: 35mm DIN rail, 18mm width per pole
- Dimensions: Approx. 72mm (W) x 90mm (H) x 77mm (D)
- Standards: BS 7671 (18th Edition), IEC/EN 60898-1
- Brand: WCED
The WKC420B must be installed by a qualified electrician in accordance with BS 7671 wiring regulations.
- DIN rail mounted (18mm per pole)
- Ensure fault level ≤10kA
- Use for resistive loads only (B Curve)
- Apply correct terminal torque
- Check enclosure space for 4-pole switching devices
