WKC 3 Pole 10kA MCB – 50A D Curve (WKC350D)
18th Ed. Compliant
2-Year Warranty
UK Stock
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The WKC350D 3 Pole 10kA MCB is a 50A D Curve breaker engineered for three-phase circuits subject to very high inrush currents. With a 10kA breaking capacity and compliance with BS 7671 (18th Edition), it provides safe and reliable protection against overloads and short-circuits. Perfect for welders, transformers, compressors, and...
The WKC350D 3 Pole 10kA MCB is a 50A D Curve breaker engineered for three-phase circuits subject to very high inrush currents. With a 10kA breaking capacity and compliance with BS 7671 (18th Edition), it provides safe and reliable protection against overloads and short-circuits. Perfect for welders, transformers, compressors, and heavy motors, this breaker prevents nuisance tripping in demanding industrial environments. Compact, DIN rail mounted, and bi-directional, it offers flexible installation.
Installer Tip: Use D Curve breakers for circuits with large inrush demand. For resistive circuits, see the B Curve. For inductive but moderate inrush, check the C Curve.
Key Features
- 50A rated current – protects large three-phase circuits
- D Curve tripping – trips at 10–20x In
- 10kA breaking capacity – safe disconnection under heavy faults
- 3 Pole design: safeguards all three live phases
- Bi-directional: can be wired top or bottom
- Applications: welders, compressors, transformers, heavy motors, industrial plant
Compare 50A 3 Pole Variants
| Model | Curve | Rated Current | Breaking Capacity |
|---|---|---|---|
| WKC350B | B Curve | 50A | 10kA |
| WKC350C | C Curve | 50A | 10kA |
| WKC350D (This Product) | D Curve | 50A | 10kA |
Where is the WKC350D used?
In heavy-duty three-phase 50A circuits such as welders, transformers, compressors, and large industrial motors.
How does D Curve compare with B and C?
B Curve trips at 3–5x In (resistive), C Curve at 5–10x In (inductive), and D Curve at 10–20x In (heavy machinery).
What does 10kA breaking capacity mean?
It’s the maximum short-circuit current the breaker can safely interrupt — suitable for industrial and commercial boards.
Is the WKC350D bi-directional?
Yes — it can be wired from either top or bottom terminals.
Is it EV or PV compatible?
No — D Curve breakers are not typically specified for EV or PV installs. They’re designed for industrial machinery with high inrush.
- Product Code: WKC350D
- Type: Miniature Circuit Breaker (MCB)
- Poles: 3P (three-phase)
- Rated Current: 50A
- Curve: D Curve
- Breaking Capacity: 10kA
- Mounting: DIN rail, 18mm per module
- Functions: Overload & short-circuit protection, switching, isolation
- Compliance: BS 7671 (18th Edition)
- Endurance: 4000 mechanical / 2000 electrical operations
- Brand: WCED
Install in commercial or industrial distribution boards where very high inrush is expected. Curve guidance:
- B Curve: resistive loads (lighting, sockets)
- C Curve: motors, HVAC, EV chargers (moderate inrush)
- D Curve: welders, transformers, heavy motors, compressors (high inrush)
Ensure fault levels do not exceed the 10kA rating. All work must comply with BS 7671 and be performed by a qualified electrician.
