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The WKC440B is a 40A 4 pole 10kA Miniature Circuit Breaker (MCB) for three-phase + neutral circuits. With its B Curve trip characteristic, this breaker is intended for resistive load circuits such as socket outlet banks, small distribution boards, and lighting groups in commercial three-phase systems, EV distribution boards, and solar PV installs.

With a 10kA breaking capacity, the WKC440B delivers safe overload and short-circuit protection while disconnecting all phases and neutral. It is DIN-rail mounted, bi-directional, and manufactured in compliance with BS 7671 (18th Edition).

Installer Tip: The 40A B Curve breaker is a solid choice for larger socket outlet circuits or small commercial distribution boards. Verify that the installation fault current does not exceed 10kA before use.

Key Features

  • 40A 4 Pole MCB – B Curve trip characteristic
  • 10kA breaking capacity – reliable in commercial & industrial installs
  • Full neutral protection: 4P switching (L1, L2, L3, N)
  • Bi-directional feed: top or bottom cable entry
  • DIN-rail mountable: 18mm width per module
  • Complies with BS 7671 (18th Edition)

Compare WKC 4 Pole 10kA MCBs (B Curve)

Model Rating Curve Breaking Capacity
WKC432B 32A B Curve 10kA
WKC440B (This Product) 40A B Curve 10kA
WKC450B 50A B Curve 10kA
WKC463B 63A B Curve 10kA
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