This guide explains everything you need to know about 1P+N RCBOs, B-curve RCBOs, Type A Rcbos, and how to match RCBO sizes such as B10 30mA 1P+N RCBO, B16 30mA 1P+N RCBO, and B32 30mA 1P+N RCBO to your specific application.
1P+N RCBO (left) occupies 1 module width, while 2P RCBO (right) occupies 2 modules. Both provide residual current and overcurrent protection.
What Is an RCBO Breaker?
An Rcbo Breaker(Residual Current Circuit Breaker with Overcurrent Protection) combines two protective functions in a single, compact device:
- Residual current protection(like an RCD) — detects Earth Leakage and disconnects the circuit to prevent electric shock.
- Overcurrent protection(like an mcb) — protects against overload and short circuit.
Compared with using a separate mcb and RCD, an RCBO provides more precise, circuit-by-circuit protection. When one circuit trips, the others continue operating.
RCBO and RCD: What's the Difference?
Many buyers search for "RCBO and RCD" because the terms are often confused. Here is the clear distinction:
| Device | Protects Against | Overcurrent Protection | Typical Use |
|---|---|---|---|
| RCD(Residual Current Device) | Earth Leakage only | No | Upstream protection for multiple circuits |
| MCB (Miniature Circuit Breaker) | Overload & short circuit | Yes | Individual circuit overcurrent protection |
| RCBO breaker | Earth leakage + overcurrent | Yes | Individual circuit, combined protection |
An RCBO essentially replaces both an RCD and an MCB for a given final circuit, providing selective tripping and saving valuable DIN rail space.
1P+N RCBO vs 2P RCBO: Pole Configuration Matters
The term "RCBO 1P+N" is the common industry shorthand for 1P+N RCBO. Both notations refer to the same device configuration:
- 1P+N RCBO (1PN RCBO): Protects and switches the phase (live) conductor. The neutral passes through the device but is typically not switched (in solid-neutral designs) or is switched mechanically linked depending on the manufacturer.
- 2P RCBO: Switches and protects both the live and neutral conductors simultaneously, providing complete isolation.
Objective comparison:
| Feature | 1P+N RCBO (RCBO 1PN) | 2P RCBO |
|---|---|---|
| Overcurrent protection | Phase only | Phase + Neutral |
| Neutral switching | Not switched (solid neutral) or switched (depending on model) | Yes, both poles switch |
| Physical width | 18 mm (1 module) | 36 mm (2 modules) |
| Typical application | Residential final circuits, lighting, sockets | Circuits requiring full isolation, commercial panels |
| Cost | More economical | Slightly higher |
Selection principle: For most residential and light commercial single-phase circuits, a 1P+N RCBO is sufficient and saves panel space. For circuits where complete isolation of both conductors is mandatory (e.g., certain commercial or industrial applications), a 2P RCBO is the correct choice.
Understanding RCBO Sizes: Rated Current Options
RCBO sizes refer to the rated current (In) the device can carry continuously. Common RCBO sizes include:
- 6A / 10A — Lighting circuits
- 16A / 20A — Socket circuits, small appliances
- 25A / 32A — Air conditioners, water heaters
- 40A / 63A — Main or sub-distribution circuits
Among the most frequently searched RCBO sizes are:
- B10 30mA 1P+N RCBO — Ideal for lighting circuits with B curve and 30mA personal protection
- B16 30mA 1P+N RCBO — The most common size for socket outlets in residential installations
- B32 30mA 1P+N RCBO — Suitable for larger loads such as air conditioners or EV charger feeders
The "B" denotes the B-curve RCBO trip characteristic, "10/16/32" is the rated current in amperes, and "30mA" is the residual operating current for personal shock protection.
B Curve RCBO vs C Curve RCBO: Choosing the Right Trip Characteristic
The trip curve determines how the RCBO breaker responds to overcurrent conditions.
B Curve RCBO
A B-curve RCBO trips at 3 to 5 times the rated current. It is designed for purely resistive loads with low inrush current:
- Lighting circuits
- General residential sockets
- Standard domestic appliances
A 1P+N RCBO B-curve device (e.g., B16 30mA 1P+N RCBO) is the default specification for the vast majority of household circuits.
C Curve RCBO
A C-curve RCBO trips at 5 to 10 times the rated current. It tolerates higher inrush currents:
- Motors and pumps
- HVAC equipment, air conditioners
- Larger LED lighting groups
- Commercial socket circuits
A 1P+N RCBO C-curve variant is recommended when the connected load has significant startup surge that would cause a B curve device to nuisance trip.
Important: Do not specify a C curve simply to mask an underlying design problem. The electrician must still verify cable sizing, fault loop impedance, and the actual inrush characteristics of the load.
Type A RCBO: Why It Matters for Modern Circuits
RCBOs are also classified by the type of residual current they can detect:
| Type | Detectable Leakage | Typical Application |
|---|---|---|
| Type AC | Sinusoidal AC only | Legacy pure AC loads (hardly used in new installations) |
| Type A RCBO | AC + pulsating DC up to 6mA | Household appliances, LED drivers, EV chargers, electronic equipment |
| Type F RCBO | AC + pulsating DC + mixed frequency | Variable-speed drives, inverter-fed equipment |
| Type B RCBO | AC + pulsating DC + smooth DC | EV chargers, PV systems, frequency converters |
A Type A RCBO is now the minimum recommended standard for modern installations because today's households and offices contain numerous electronic loads that generate pulsating DC leakage. Type AC alone is no longer sufficient for circuits with LED lighting, smart appliances, or EV charging equipment.
Quick Selection Reference
| Circuit / Load | Recommended RCBO |
|---|---|
| Lighting (residential) | B10 30mA 1P+N RCBO, Type A |
| Socket outlets (residential) | B16 30mA 1P+N RCBO, Type A |
| Air conditioner / HVAC | B32 30mA 1P+N RCBO, Type A, C curve |
| EV charger (with 6mA DC detection) | B32 30mA 1P+N RCBO, Type A |
| EV charger (without DC detection) | Type B RCBO required |
| Motor / pump circuits | C curve RCBO, Type A |
Introducing the ELBO Series 1P+N RCBO Breaker
The ELBO series 1P+N RCBO breaker is engineered to meet the demands of modern electrical installations. It is available in B curve, multiple RCBO sizes including B10, B16, and B32, with Type A versions for different site requirements.
Key technical specifications:
- Standard: EN IEC 61009-1 compliant
- Pole configuration: 1P+N, compact 17.8 mm width (1 module)
- Rated current (In): 6A, 10A, 13A, 16A, 20A, 25A, 32A, 40A
- Rated residual current (Idn): 10mA, 30mA, 100mA, 300mA
- Trip curve: B curve and C curve options
- Breaking capacity: 6kA and 10kA
- Residual current trip time: less than or equal to 0.1 seconds
- Terminals: Universal lug and pin type, compatible with 16 mm2 flexible or 25 mm2 rigid cables
- Mounting: 35 mm DIN rail
- Operating temperature: -25 degrees C to +40 degrees C
- Endurance: 4,000 electrical operations, 10,000 mechanical operations
Whether you need a B10 30mA 1P+N RCBO for lighting, a B16 30mA 1P+N RCBO for sockets, or a B32 30mA 1P+N RCBO for heavier loads, the ELBO series provides a reliable, standards-compliant solution.
FAQ
Is 1PN RCBO the same as 1P+N RCBO?
Yes. "1PN" is the common shorthand notation for "1P+N RCBO" across the European electrical industry. You will see both terms used interchangeably in product catalogues and datasheets.
Do I need a Type A RCBO or Type AC RCBO?
A Type A RCBO covers pulsating DC leakage, which is widely recommended for modern circuits with EV chargers, LED loads, and electronic appliances. Type AC only detects pure AC leakage and is hardly used in new installations. For virtually all contemporary residential and commercial circuits, Type A is the minimum standard.
When should I choose a 1PN RCBO B curve vs 1PN RCBO C curve?
A 1PN RCBO B curve trips at 3-5 times rated current and is ideal for purely resistive loads such as lighting and standard sockets. A 1PN RCBO C curve trips at 5-10 times rated current and is better suited for circuits with moderate inrush currents, such as motors, HVAC equipment, and larger commercial socket circuits.
What is the difference between an RCBO and an RCD?
An RCD (Residual Current Device) only provides earth leakage protection. An RCBO (Residual Current Circuit Breaker with Overcurrent Protection) combines residual current protection with overcurrent protection (overload and short circuit) in a single device, making it equivalent to an RCD + MCB combination.
Which RCBO size do I need for my socket circuit?
For a typical residential socket circuit, a B16 30mA 1P+N RCBO (16A rated current, 30mA residual sensitivity, B curve, Type A) is the most common specification. However, the exact rating should be calculated based on the expected load current, cable size, and local wiring regulations. A B10 30mA 1P+N RCBO is common for lighting, and a B32 30mA 1P+N RCBO is often used for larger appliances like air conditioners.
Conclusion
Selecting the right 1P+N RCBO breaker involves balancing four key parameters: pole configuration, RCBO sizes (rated current), trip curve (B-curve RCBO or C-curve), and residual current type (Type A RCBO). By understanding the differences between RCBO 1PN and 2P, and knowing when to specify a B10, B16, or B32 30mA 1P+N RCBO, engineers and installers can ensure both safety and compliance.
The ELBO series 1P+N RCBO breaker delivers all these configuration options in a compact, IEC 61009-compliant design — giving you the flexibility to protect any single-phase circuit with confidence.
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