High Immunity Type A Mini RCBO – 20A B Curve (WRB120B-030)
18th Ed. Compliant
2-Year Warranty
UK Stock
Free Delivery £30+
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The WRB120B-030 High Immunity Type A Mini RCBO is a 20A B Curve protective device designed for residential and commercial circuits. Its compact 18mm width combines overload, short-circuit, and residual current protection in one unit. With 30mA Type A sensitivity and high immunity against nuisance tripping, it’s well suited to...
The WRB120B-030 High Immunity Type A Mini RCBO is a 20A B Curve protective device designed for residential and commercial circuits. Its compact 18mm width combines overload, short-circuit, and residual current protection in one unit. With 30mA Type A sensitivity and high immunity against nuisance tripping, it’s well suited to socket circuits, small fixed appliances, and lighting loads where compliance with 18th Edition standards is required.
Installer Tip: Select the 20A B Curve for small appliance and socket circuits up to 20A. If the circuit includes motors or higher inrush equipment, use the 20A C Curve variant.
Key Features
- 20A rated current – ideal for sockets, small appliances, and lighting
- B Curve tripping – suited to general residential loads
- Type A sensitivity – detects AC + pulsating DC leakage
- High immunity – reduces nuisance trips under harmonics
- Compact 18mm width – maximises usable ways in consumer units
- Switched live & neutral – ensures full isolation
- Bi-directional – safe for PV and EV systems
Compare Mini RCBO Variants
| Model | Rated Current | Curve | Type | Width |
|---|---|---|---|---|
| WRB120B-030 (This Product) | 20A | B Curve | Type A, High Immunity | 18mm |
| WRB120C-030 | 20A | C Curve | Type A, High Immunity | 18mm |
What is the WRB120B-030 best used for?
It’s designed for 20A socket, lighting, or small appliance circuits in residential and commercial installs.
When would I choose the C Curve instead?
The 20A C Curve is better suited for circuits with motors, pumps, or equipment that draws higher inrush current at start-up.
Does this RCBO comply with 18th Edition regulations?
Yes – with Type A detection and 30mA sensitivity, it meets current wiring regulations, including EV and PV installs.
Does it switch both live and neutral?
Yes – the switched neutral design ensures both conductors are isolated in the event of a fault.
- Product Code: WRB120B-030
- Rated Current: 20A
- 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 WRB120B-030 installs in standard DIN rail consumer units and compact boards. All installation and testing must be carried out by a qualified electrician.
- Use on socket, small appliance, or mixed lighting circuits up to 20A
- B Curve – designed for general domestic and commercial loads
- Single-module 18mm width – space-saving for retrofit installs
- Switched neutral – simplifies testing and isolation
- Compatible with PV and EV applications requiring Type A detection
