WKC 3 Pole 10kA MCB – 40A C Curve (WKC340C)
18th Ed. Compliant
2-Year Warranty
UK Stock
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The WKC340C 3 Pole 10kA MCB is a 40A C Curve breaker built for protecting three-phase circuits with moderate inrush currents. Rated at 10kA breaking capacity, it provides safe disconnection during overload and short-circuit faults. Compact, bi-directional, and DIN rail mounted, it’s a reliable choice for EV charging points, solar...
The WKC340C 3 Pole 10kA MCB is a 40A C Curve breaker built for protecting three-phase circuits with moderate inrush currents. Rated at 10kA breaking capacity, it provides safe disconnection during overload and short-circuit faults. Compact, bi-directional, and DIN rail mounted, it’s a reliable choice for EV charging points, solar PV distribution, HVAC systems, and industrial boards.
Installer Tip: Select a C Curve breaker when dealing with inductive circuits that generate moderate inrush currents. For lighting or socket loads, see the B Curve. For heavy inrush machinery, use the D Curve.
Key Features
- 40A rated current – protects larger three-phase inductive loads
- C Curve tripping – trips at 5–10x In
- 10kA breaking capacity – withstands high fault currents
- 3 Pole protection – covers all three live phases
- Bi-directional: allows flexible wiring from top or bottom
- Applications: EV charge points, motors, HVAC, solar PV, industrial boards
Compare 40A 3 Pole Variants
| Model | Curve | Rated Current | Breaking Capacity |
|---|---|---|---|
| WKC340B | B Curve | 40A | 10kA |
| WKC340C (This Product) | C Curve | 40A | 10kA |
| WKC340D | D Curve | 40A | 10kA |
What is the WKC340C best suited for?
Protecting three-phase 40A circuits such as HVAC, motors, EV chargers, and solar PV arrays.
How does C Curve compare with B and D?
B Curve trips at 3–5x In, best for resistive loads. C Curve trips at 5–10x In, ideal for inductive loads. D Curve trips at 10–20x In for heavy machinery.
What does 10kA breaking capacity mean?
It’s the maximum fault current the breaker can safely interrupt. 10kA is standard for commercial and industrial systems.
Is this breaker bi-directional?
Yes — it supports wiring from either the top or bottom terminals.
Is it suitable for EV and PV installs?
Yes — widely used in EV charging boards and solar PV distribution.
- Product Code: WKC340C
- Type: Miniature Circuit Breaker (MCB)
- Poles: 3P (three-phase)
- Rated Current: 40A
- Curve: C 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
Mount inside commercial or industrial distribution boards. Ensure correct curve selection:
- B Curve: for standard resistive loads
- C Curve: for inductive loads (motors, HVAC, EV chargers)
- D Curve: for heavy inrush applications like welders and transformers
Always verify the site’s fault level against the 10kA breaking capacity. Installation must follow BS 7671 and be performed by a qualified electrician.
