50A 4 Pole 10kA MCB B Curve – WKC450B
18th Ed. Compliant
2-Year Warranty
UK Stock
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The WKC450B is a 50A 4 pole 10kA Miniature Circuit Breaker (MCB) designed for three-phase + neutral systems. With a B Curve trip characteristic, it is intended for resistive load applications such as socket outlet groups, small power distribution boards, and general lighting circuits in commercial three-phase systems, EV distribution...
The WKC450B is a 50A 4 pole 10kA Miniature Circuit Breaker (MCB) designed for three-phase + neutral systems. With a B Curve trip characteristic, it is intended for resistive load applications such as socket outlet groups, small power distribution boards, and general lighting circuits in commercial three-phase systems, EV distribution boards, and solar PV installs.
Providing a 10kA breaking capacity, the WKC450B offers reliable protection against overload and short-circuits while ensuring complete neutral disconnection. It is bi-directional, DIN-rail mounted, and manufactured to BS 7671 (18th Edition) standards.
Installer Tip: The 50A B Curve breaker is suitable for high-demand resistive circuits. Always verify that the fault current at the installation point does not exceed 10kA.
Key Features
- 50A 4 Pole MCB – B Curve characteristic
- 10kA breaking capacity – safe for commercial & industrial systems
- Full neutral isolation: 4P switching (L1, L2, L3, N)
- Bi-directional feed: top or bottom cable 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 |
---|---|---|---|
WKC440B | 40A | B Curve | 10kA |
WKC450B (This Product) | 50A | B Curve | 10kA |
WKC463B | 63A | B Curve | 10kA |
What applications suit a 50A B Curve breaker?
It is typically used for high-demand resistive load circuits such as large socket groups or small commercial distribution panels.
Why use a 4-pole breaker here?
A 4-pole breaker disconnects the neutral as well as all three phases, giving full protection for three-phase + N circuits.
Is the WKC450B suitable for EV or solar installs?
Yes — provided the load is resistive and the board fault level does not exceed 10kA. For inductive or inrush loads, select a C or D Curve variant.
Does it comply with UK standards?
Yes, it is manufactured to BS 7671 (18th Edition) and IEC/EN 60898-1 standards.
- Model: WKC450B
- Type: Miniature Circuit Breaker (MCB)
- Current Rating: 50A
- 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)
- Compliance: BS 7671 (18th Edition), IEC/EN 60898-1
- Brand: WCED
The WKC450B must be installed by a qualified electrician in accordance with BS 7671 wiring regulations.
- Mount on 35mm DIN rail (18mm per pole)
- Check that system fault current ≤10kA
- Use only for resistive load applications (B Curve)
- Apply correct tightening torque on terminals
- Ensure adequate enclosure space for 4P switching