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B40 40A B Curve 30mA A Type RCBO (NB3LEG)

A reliable 40A residual current circuit breaker with over-current protection. Type A leakage detection, B Curve tripping, 30mA sensitivity and 6kA fault capacity make this ideal for residential and light commercial circuits.

Dual Protection in One Unit: Combines overload, short-circuit and residual current protection for comprehensive safety. Ideal for Modern Electrical Loads: Type A detection senses both AC and pulsating DC leakage from electronic devices. Reliable Trip Performance: B Curve characteristic helps reduce unnecessary trips while still protecting circuits with moderate inrush. High Fault Capacity: 6 kA short-circuit breaking capacity helps safeguard circuits against severe electrical faults. Easy Install and Monitor: DIN rail mounting and clear contact position indicator make installation and checks quick and simple.
£26.40
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SKU: NB3LEG-B40
AVAILABLE IN 7-10 DAYS
Product Details

The Chint NB3LEG‑B40 40A B Curve 30mA A Type RCBO combines critical electrical protection and compact design in one essential safety device. Designed for use in single-phase circuits, this RCBO protects your wiring and appliances by detecting both overloads and earth leakage faults. Built to meet BS EN safety standards, it reliably safeguards electrical installations in homes, workshops, offices, and light commercial settings.

Engineered for modern electrical systems, this RCBO integrates over-current protection and residual current detection into a single module that fits neatly on a standard DIN rail. With a B Curve characteristic, it responds quickly to moderate surge currents without nuisance trips, making it suitable for general circuits such as lighting, sockets, and everyday appliances. Its Type A residual current detection senses both alternating and pulsating DC leakage, offering broader protection for circuits that include electronic loads such as LED drivers, appliances, or chargers.

The device has a rated current of 40 amps and a residual current trip threshold of 30mA, ideal for personal protection against electric shock and fire risk. The robust 6kA short-circuit breaking capacity ensures reliable disconnection during faults, helping prevent damage to equipment and wiring. Compact and lightweight, the RCBO mounts easily on a 35 mm DIN rail to make installation fast and straightforward.

Built for durability and performance, this unit includes a clear contact position indicator that shows at a glance whether the circuit is closed or open. Whether you are upgrading existing protection or specifying new installations, the NB3LEG‑B40 is a dependable choice for enhanced circuit safety and compliance.

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Tracked Delivery (Currently 1-3 business days):

  • Free over £150.
  • £5.99 for orders under £150.
  • £5.99 for orders under £50.

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  • £15 Flat Rate.

Collection:

  • Free to collect from our warehouse.

Pre-Order:

  • 5-10 Business Days delivery unless otherwise stated.

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