High Immunity Type A Mini RCBO – 20A B Curve (WRB120B-030)
18th Ed. Compliant
2-Year Warranty
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WRB120B-030 is a 20A B Curve high immunity Type A mini RCBO designed for general-purpose domestic and commercial circuits. It combines overload, short-circuit, and residual current protection in one compact single-module device, making it ideal where board space is limited. As part of the Whitecliffe WRB range, this RCBO provides...
WRB120B-030 is a 20A B Curve high immunity Type A mini RCBO designed for general-purpose domestic and commercial circuits. It combines overload, short-circuit, and residual current protection in one compact single-module device, making it ideal where board space is limited.
As part of the Whitecliffe WRB range, this RCBO provides Type A protection, detecting standard AC faults and pulsating DC components. The high immunity design helps reduce nuisance tripping, while the built-in switched neutral provides full isolation of live and neutral conductors on a faulty circuit.
Installer Tip: Choose the 20A B Curve for general-purpose socket and small appliance circuits. Where the circuit has higher startup or inrush demand, a 20A C Curve variant may be more suitable.
Key Features
- 20A rated current – suited to general-purpose circuits
- B Curve tripping – suitable for standard domestic and commercial loads
- Type A protection – detects AC and pulsating DC components
- High immunity design – helps reduce nuisance tripping
- 30mA residual current protection
- 6kA breaking capacity
- 1P+N format – switched live and neutral
- Compact 18mm width – saves space in the board
- Bi-directional operation – suitable for modern PV and EV system layouts
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 WRB120B-030 best used for?
It is designed for 20A general-purpose domestic and commercial circuits where a B Curve high immunity Type A RCBO is required.
When would I choose the C Curve version instead?
The 20A C Curve version is more suitable for circuits with higher startup or inrush demand.
What does Type A protection mean?
Type A protection means the device can detect standard AC faults as well as pulsating DC residual current components.
Does WRB120B-030 switch both live and neutral?
Yes. It is a 1P+N device with switched neutral, so both conductors are isolated on a fault.
Is this RCBO suitable for PV or EV system layouts?
Yes. The WRB range is designed for bi-directional use, making it suitable for modern PV and EV system arrangements where applicable.
- Product Code: WRB120B-030
- Rated Current: 20A
- Curve: B Curve
- Breaking Capacity: 6kA
- Poles: 1P+N (switched live and neutral)
- Trip Sensitivity: 30mA
- Earth Leakage Detection: Type A (AC + pulsating DC)
- Rated Voltage: 230V
- Rated Frequency: 50/60Hz
- Module Width: 18mm
- Protection Degree: IP20
- Standard: IEC/EN 61009-1
- Operation: Bi-directional
- Mounting: DIN rail EN 60715 (35mm)
WRB120B-030 is designed for installation in compatible DIN rail consumer units and distribution boards. Installation and testing must be carried out by a qualified electrician.
- Use on general-purpose 20A circuits where a B Curve device is appropriate
- Ensure correct line and neutral termination before energising
- Allow for the compact 18mm single-module width in board planning
- Switched neutral design supports full isolation of the faulty circuit
- Test protective operation during commissioning
