High Immunity RCBO – 20A B Curve, Type A, 30mA
18th Ed. Compliant
2-Year Warranty
UK Stock
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The WER20B-030 is a 20A B Curve High Immunity Type A RCBO designed for residential and light commercial circuits including solar PV, battery storage, and EV-ready boards. It combines overload, short-circuit, and 30mA residual current protection in one device, while its high immunity design helps prevent nuisance tripping in inverter-fed...
The WER20B-030 is a 20A B Curve High Immunity Type A RCBO designed for residential and light commercial circuits including solar PV, battery storage, and EV-ready boards. It combines overload, short-circuit, and 30mA residual current protection in one device, while its high immunity design helps prevent nuisance tripping in inverter-fed or noisy environments.
Featuring double pole disconnection and bi-directional wiring, this RCBO is a versatile choice for compliance with the 18th Edition Wiring Regulations (Amendment 2).
Installer Tip: The B Curve is typically used for lighting and socket circuits where low inrush current is expected. For EV chargers, motors, or heat pump circuits, choose the C Curve version.
Key Features
- 20A B Curve Type A RCBO – protects against overload, short-circuit and earth leakage
- High immunity – resists nuisance trips from harmonics and transients
- 30mA sensitivity – compliant with Amendment 2
- 10kA breaking capacity – suitable for residential and light commercial installs
- Double pole disconnection – safe isolation of live and neutral
- Bi-directional wiring – line/load reversible for solar & EV systems
- Complies with BS EN 61009 & 18th Edition Wiring Regulations
Compare High Immunity RCBOs
| Model | Rating | Curve | Application |
|---|---|---|---|
| WER16B-030 | 16A | B Curve | Lighting / Domestic Circuits |
| WER20B-030 (This Product) | 20A | B Curve | Domestic / Light Commercial |
| WER20C-030 | 20A | C Curve | Motors / EV / Inrush Loads |
| WER32B-030 | 32A | B Curve | Heavier Duty Circuits |
When should I use a 20A B Curve RCBO?
It’s suited for general domestic and light commercial circuits where low inrush current is expected.
Why high immunity?
Prevents false tripping from transient voltages and harmonics – common in inverter-heavy environments like solar PV systems.
Is this suitable for EV chargers?
While possible, C Curve RCBOs are recommended for most EV installs due to inrush current. This B Curve version is better for standard circuits.
Does it disconnect both poles?
Yes, it provides full double pole disconnection of live and neutral conductors.
- Type: A (detects AC + pulsating DC leakage)
- Rating: 20A
- Trip Curve: B
- Sensitivity: 30mA
- Breaking Capacity: 10kA
- Poles: 2 (double pole)
- Wiring: Bi-directional
- SKU: WER20B-030
- Standards: BS EN 61009 / IEC 61009
Designed for distribution boards and consumer units requiring high immunity RCBO protection. Suitable for domestic and light commercial systems including solar PV and EV-ready installs.
- DIN rail mounted
- Ensure load rating suits the connected circuit
- Bi-directional wiring allows flexible line/load connection
- Installation must be carried out by a qualified electrician
