10kA MCBs for High Fault-Level Circuits
10kA MCBs are miniature circuit breakers designed for circuits with higher prospective fault currents. They offer a higher breaking capacity than standard domestic breakers, making them suitable for commercial boards, industrial panels, three-phase supplies and installations close to the transformer where fault levels are elevated.
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These MCBs provide reliable overcurrent and short-circuit protection with 10,000 A breaking capacity, ensuring safe operation in environments where higher fault energy is expected. They are available in a full range of current ratings and tripping curves, allowing installers to select the correct device based on circuit behaviour and load type.
- 10kA breaking capacity for high fault-level environments
- Available in B and C curves for domestic, commercial and industrial applications
- Wide rating range including 6A, 10A, 16A, 32A and higher
- Single-module DIN-rail format for easy installation
- Stable disconnection under heavy short-circuit conditions
10kA MCBs are routinely specified in commercial distribution boards, three-phase supply setups, and circuits located near the incoming supply where prospective fault currents exceed the capabilities of standard 6kA breakers.
25A 4 Pole 10kA MCB C Curve – WKC425C
£14.16
The WKC425C is a 25A 4 pole 10kA Miniature Circuit Breaker (MCB) designed to protect three-phase + neutral systems. With its C Curve trip profile, it is suitable for inductive loads such as motors, pumps, HVAC units, and EV charger circuits in commercial distribution boards,...
25A 4 Pole 10kA MCB B Curve – WKC425B
£14.16
The WKC425B is a 25A 4 pole 10kA Miniature Circuit Breaker (MCB) designed for three-phase + neutral circuits. With a B Curve trip profile, it is best used for resistive loads such as lighting banks, socket circuits, and small distribution panels in commercial three-phase boards,...
20A 4 Pole 10kA MCB D Curve – WKC420D
£14.16
The WKC420D is a 20A 4 pole 10kA Miniature Circuit Breaker (MCB) designed for three-phase + neutral protection. With its D Curve trip characteristic, it is suited to high inrush load circuits such as welders, transformers, heavy motors, and industrial machinery. Typical use includes commercial...
20A 4 Pole 10kA MCB C Curve – WKC420C
£14.16
The WKC420C is a 20A 4 pole 10kA Miniature Circuit Breaker (MCB) designed for three-phase + neutral systems. With its C Curve trip characteristic, it is suited to inductive load circuits such as motors, HVAC, pumps, and EV charging sub-circuits in commercial boards, EV distribution...
20A 4 Pole 10kA MCB B Curve – WKC420B
£14.16
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...
What Makes a 10kA MCB Different?
A 10kA MCB is engineered to interrupt short-circuits up to 10,000 amps without catastrophic failure. This higher breaking capacity ensures safety and compliance in installations where the calculated PFC (Prospective Fault Current) exceeds domestic levels.
Where 10kA MCBs Are Used
- Commercial and industrial distribution boards
- Three-phase supplies with higher fault levels
- Installations close to the service head or transformer
- Workshops, plant rooms and machinery feeds
- Retrofits where standard 6kA devices are insufficient
B Curve vs C Curve 10kA MCBs
B Curve: Trips between 3–5 × rated current. Suitable for lighting circuits and resistive loads.
C Curve: Trips between 5–10 × rated current. Ideal for motor-driven or surge-prone circuits.
When to Specify 10kA Breaking Capacity
A 10kA MCB should be used whenever fault calculations or the measured PFC approach the limit of a 6kA device. Commercial boards, workshops and three-phase panels often require this rating as standard.
- Higher fault-current environment
- Near incomer or transformer
- Industrial machinery circuits
- Large commercial properties
Compliance & Standards
All 10kA MCBs in this category are designed to comply with BS EN 60898 and meet the performance and safety expectations of the 18th Edition Wiring Regulations. They are suitable for new installations and replacement upgrades requiring higher fault protection.
Installer Benefits
10kA MCBs provide confidence and compliance in higher-risk environments. Their robust construction, predictable tripping characteristics and wide rating availability make them a dependable choice for professional electricians working on commercial, industrial and high-demand domestic installations.