Industrial Grade WSB1LE-80 4P RCBO

The mainstream classification dimensions in the industry are as follows:

By number of poles: 1P+N, 2P, 3P, 3P+N, 4P;

By leakage trip type: Type AC (only AC leakage), Type A (AC + pulsating DC leakage), Type B (all types of AC and DC leakage);

By overcurrent trip curve: Type B, Type C, Type D;

By operating time: Instantaneous type, time-delay type (Type S, for graded protection);

By rated current: Full series specifications from 6A to 125A.

IEC 61009 is the general standard for Residual current operated circuit-breakers with integral overcurrent protection issued by the International Electrotechnical Commission. RCBOs complying with this standard are compliant integrated residual current breakers with overcurrent, covering all RCBO products of different leakage types, trip curves and pole specifications. It is a universal product specification in the global low-voltage electrical industry.

The core difference lies in pole protection capability and breaking range:

• 1P+N RCBO: Only the live pole has complete overload and short-circuit trip mechanisms, the neutral pole has no protection and only breaks synchronously. It has small size and low cost, and neutral and live lines cannot be reversely connected. Suitable for ordinary single-phase terminal circuits.
• 2P RCBO: Both live and neutral poles have complete protection trip mechanisms, and both poles can be disconnected simultaneously in case of fault. It has more thorough electrical isolation, reverse connection of neutral and live lines does not affect protection function, with higher safety. Suitable for incoming main switches and circuits with high safety requirements.

The full name remains unchanged: Residual Current Breaker with Overcurrent. 4P RCBO specifically refers to 4-pole specification products adapted to three-phase four-wire systems. It can perform leakage detection and overcurrent protection on three phase lines + neutral line simultaneously, and disconnect all poles in case of fault. It is mainly used in industrial three-phase power distribution and high-power three-phase load scenarios.

Here it refers to the difference in leakage trip types, and the core difference is the types of leakage current that can be detected:

• Type A RCBO: Can detect sinusoidal AC residual current + pulsating DC residual current, suitable for loads with rectifier circuits and switching power supplies, such as inverter equipment and electronic appliances. It is the mainstream leakage type in commercial and industrial scenarios.
• Type B RCBO: Can detect all types of residual current: AC, pulsating DC and smooth DC. Suitable for equipment with DC circuits, such as photovoltaic systems, DC charging piles and industrial variable frequency drive equipment, with the most comprehensive leakage protection coverage.

There is no absolutely optimal model. The one that adapts to scenario requirements and complies with corresponding standards is the best choice:

• Ordinary civil socket circuits: Type C trip, 30mA instantaneous, Type A leakage can meet the demand;
• Inverter equipment and charging pile circuits: Priority is given to Type A or Type B leakage characteristics;
• Power circuits such as motors and air compressors: Choose Type D trip curve to withstand starting inrush;
• Industrial three-phase four-wire systems: Choose 4P specification to realize all-pole protection.

Here Type B/C refer to overcurrent trip curve types. The two have exactly the same leakage protection function, and the difference only lies in overcurrent trip characteristics:

• Type B RCBO: Instantaneous trip current is 3~5 times rated current, with high overcurrent sensitivity, suitable for pure resistive three-phase loads without starting inrush;
• Type C RCBO: Instantaneous trip current is 5~10 times rated current, can tolerate starting inrush of ordinary inductive loads, suitable for commercial mixed loads and small power circuits, and is the mainstream choice for commercial power distribution.

Type A RCBO refers to RCBO with Type A leakage trip characteristic. In addition to power frequency sinusoidal AC leakage, it can also detect half-wave pulsating DC residual current. It has better compatibility with electronic loads with rectifier bridges and switching power supplies, avoiding the problem of insensitivity and refusal to operate for DC leakage of traditional Type AC products. It is the mainstream leakage protection grade in current civil and commercial scenarios.

“Type 4” is not a universal standard term for low-voltage circuit breakers. There are usually two interpretations in the industry:

The 4th grade classified by breaking capacity level, corresponding to high breaking capacity grade, generally referring to breaking specifications of 10kA and above;

The 4th category classified by trip characteristics in some regional standards, corresponding to Type D trip curve with high inrush withstand capability, suitable for heavy-starting inductive loads.
The international standard classification is the B/C/D trip curve system, and the expression “Type 4” is not standardized.

There is no absolute superiority, select according to circuit protection requirements:

• MCB: Only provides overload and short-circuit protection, with low cost and small size. Suitable for pure power circuits, main lighting circuits, etc. without leakage risk.
• RCBO: Integrates triple protection of leakage, overload and short-circuit, with higher safety level. One unit can replace the MCB+RCD combination and save installation space; suitable for socket circuits, humid environments such as kitchen and bathroom, outdoor circuits and other scenarios prone to leakage and in contact with human body.