High Immunity Type A Mini RCBO – 40A B Curve (WRB140B-030)
18th Ed. Compliant
2-Year Warranty
UK Stock
Free Delivery £30+
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The WRB140B-030 High Immunity Type A Mini RCBO is a 40A B Curve protective device for residential and commercial circuits requiring higher current handling. At just 18mm wide, it combines overload, short-circuit, and residual current protection in a single compact module. With 30mA Type A sensitivity and a high-immunity build,...
The WRB140B-030 High Immunity Type A Mini RCBO is a 40A B Curve protective device for residential and commercial circuits requiring higher current handling. At just 18mm wide, it combines overload, short-circuit, and residual current protection in a single compact module. With 30mA Type A sensitivity and a high-immunity build, it ensures safe and stable protection for EV chargers, socket outlets, and fixed appliance circuits in line with 18th Edition standards.
Installer Tip: Choose the 40A B Curve for higher-load socket or appliance circuits. If protecting motors or equipment with higher inrush currents, use the 40A C Curve variant.
Key Features
- 40A rated current – protects larger socket and appliance circuits
- B Curve tripping – suited to residential and light commercial applications
- Type A sensitivity – detects AC + pulsating DC leakage
- High immunity design – minimises false tripping under harmonics
- Compact 18mm module – ideal for retrofit boards
- Switched live & neutral – ensures complete isolation
- Bi-directional – safe for EV and PV installs
Compare Mini RCBO Variants
| Model | Rated Current | Curve | Type | Width |
|---|---|---|---|---|
| WRB140B-030 (This Product) | 40A | B Curve | Type A, High Immunity | 18mm |
| WRB140C-030 | 40A | C Curve | Type A, High Immunity | 18mm |
What’s the WRB140B-030 best used for?
It’s ideal for higher-load socket or appliance circuits requiring 40A protection in residential or light commercial boards.
When should I choose the C Curve instead?
The 40A C Curve is better for circuits with motors, pumps, or tools that produce high inrush currents.
Is the WRB140B-030 compliant with the 18th Edition?
Yes – it provides 30mA Type A protection with high immunity, meeting all current wiring regulations.
Does it isolate both conductors?
Yes – both live and neutral are switched, providing full isolation during a fault or trip.
- Product Code: WRB140B-030
- Rated Current: 40A
- Curve: B Curve
- Breaking Capacity: 6kA
- Poles: 1P + switched neutral
- Trip Sensitivity: 30mA
- Earth Leakage Detection: Type A (AC + pulsating DC)
- Module Width: 18mm
- Dimensions: 18 × 90 × 77 mm
- Standards: BS EN 61009-1
The WRB140B-030 installs into standard DIN rail consumer units or distribution boards. All work must be carried out by a qualified electrician.
- Best for higher-load socket, sub-main, or appliance circuits rated at 40A
- B Curve – for standard residential and commercial usage
- Single-module 18mm design – maximises space in consumer units
- Switched neutral for safe testing and full isolation
- Meets 18th Edition wiring requirements for Type A protection
