High Immunity Type A Mini RCBO – 25A B Curve (WRB125B-030)
18th Ed. Compliant
2-Year Warranty
UK Stock
Free Delivery £30+
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The WRB125B-030 High Immunity Type A Mini RCBO is a 25A B Curve protective device that combines overload, short-circuit, and residual current protection in a single compact unit. At just 18mm wide, it’s ideal for space-limited boards in residential or light commercial installs. With 30mA Type A sensitivity and high...
The WRB125B-030 High Immunity Type A Mini RCBO is a 25A B Curve protective device that combines overload, short-circuit, and residual current protection in a single compact unit. At just 18mm wide, it’s ideal for space-limited boards in residential or light commercial installs. With 30mA Type A sensitivity and high immunity against nuisance tripping, it ensures safe operation on socket, appliance, and lighting circuits in line with 18th Edition standards.
Installer Tip: Use the 25A B Curve for small power circuits and appliances where a 25A rating is required. For inrush-heavy circuits, choose the 25A C Curve variant.
Key Features
- 25A rated current – protects medium-load circuits
- B Curve tripping – suited for standard residential and light commercial use
- Type A sensitivity – detects AC + pulsating DC leakage
- High immunity design – reduces false tripping
- Compact 18mm width – ideal for retrofit and consumer unit upgrades
- Switched live & neutral – full circuit isolation
- Bi-directional – suitable for PV and EV systems
Compare Mini RCBO Variants
Model | Rated Current | Curve | Type | Width |
---|---|---|---|---|
WRB125B-030 (This Product) | 25A | B Curve | Type A, High Immunity | 18mm |
WRB125C-030 | 25A | C Curve | Type A, High Immunity | 18mm |
Where is a 25A B Curve RCBO typically used?
It’s ideal for socket and small appliance circuits that need a 25A protective device.
When would I choose the 25A C Curve instead?
If the load involves motors, pumps, or other equipment with higher inrush currents, the C Curve version is the better choice.
Is the WRB125B-030 compliant with modern wiring regulations?
Yes. With 30mA Type A protection and high immunity, it fully complies with the 18th Edition standards.
Does it isolate both live and neutral?
Yes – the switched neutral ensures complete disconnection of both conductors during a fault.
- Product Code: WRB125B-030
- Rated Current: 25A
- 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 WRB125B-030 is designed for DIN rail consumer units and compact distribution boards. Installation and testing must be carried out by a qualified electrician.
- Best for socket and appliance circuits requiring 25A protection
- B Curve – standard for residential and small commercial applications
- 18mm single-module design – space saving for crowded boards
- Switched neutral for easier testing and safer isolation
- Complies with 18th Edition regulations for Type A devices