The Wylex NHXS1B40 40A RCBO is a high-performance residual current circuit breaker with overcurrent protection, combining the benefits of an MCB and RCD in a compact module. With a 40A rating, Type B tripping curve, and 30mA earth leakage sensitivity, this RCBO is ideal for safeguarding lighting and low-load circuits in both domestic and commercial installations. Whether you're upgrading a consumer unit or designing a new system, this SP+N device offers maximum safety with minimal space usage.
Built for 6kA short-circuit protection, the NHXS1B40 ensures circuits are disconnected immediately during faults, preventing overheating and fire hazards. The Type A RCD function detects both AC and pulsating DC leakage currents, making it fully compliant with modern appliance standards and 18th Edition wiring regulations. Its Single Pole + Neutral (SP+N) design means only the live conductor is interrupted while maintaining a neutral connection, minimizing unnecessary power disruptions.
Designed to seamlessly integrate with Wylex NH boards, this RCBO slots easily onto a DIN rail, with clearly labeled terminals and minimal wiring. The slim single-module format helps electricians save valuable board space while maintaining full circuit separation and protection. Whether retrofitting or installing new, this unit delivers trusted performance, long-term durability, and safety peace of mind in one device.
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Almost all orders placed before 1.00pm (Monday-Friday) will be despatched the same day, (providing we have the items in stock).
We offer the following delivery options:
For orders under £50, please see the following delivery tariffs. Please note that some delivery locations / times (see below) will incur additional charges.
We are also able to offer the following timed deliveries.
Delivery Locations Incurring Extra Charges for signed for deliveries.
The following locations will incur additional charges if you select a signed for delivery (or for large items which require delivery by courier):
If you have any specific delivery requirements, call our sales team on 01793 863409.
Our aim is to provide you with the highest levels of service possible and this extends to our flexible and customer-friendly policies.
Please do not return any items to Heathfield LED without first contacting us by phone or email.
phone: 01793 863409 (9am to 5pm Monday to Friday)
email : returns@heathfieldled.co.uk
If you wish to return goods for any reason please supply the following information:-
We will do everything possible to comply with reasonable requests for returns and will issue any refund due to you as promptly as possible.
If you have any concerns or questions please call or e-mail us!
What doesn’t our warranty cover?
In any instance where your bulb has developed a fault, we will do our utmost to replace it or offer a full refund (provided the item is still within its stated warranty period). However, if it becomes apparent that the product has been misused, tampered with or modified in any way, we will view this as having voided its warranty.
‘Misuse” includes, but is not limited to, incorrect operation by the user, use of non-dimmable bulbs on a dimmable circuit or connection to or operation with an unsuitable power supply. ‘Tampering’ or ‘modification’ can be interpreted as any activity designed to alter the product in such a way that it can be used in a manner that wasn’t intended by its original design. This can include rewiring, removing plugs, home repairs or changing components. Unfortunately, we won’t be able to replace any item that has undergone any such process.
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