A Residual Amperage Operated Circuit Breaker (RCBO) is a protective device that combines the functions of a residual amperage detector and a miniature circuit breaker. It detects earth leakage currents and interrupts the circuit when leakage exceeds a preset threshold. It also responds to overload and short-circuit conditions. The SWM6LS-125 Residual Amperage Operated Circuit Breaker is designed for rated currents up to 125 A, making it suitable for main distribution boards, industrial panels, and large commercial loads.
The SWM6LS-125 is applied in environments where both personnel protection and equipment protection are critical. Typical use cases include:
For projects that require a singielectric RCBO with high breaking capacity and adjustable residual amperage sensitivity, the SWM6LS-125 offers a compact, DIN-rail mounted solution.
The internal architecture of the SWM6LS-125 includes a amperage transformer that continuously monitors the vector sum of the phase and neutral currents. When an earth fault causes a leakage amperage to return through an unintended path, the vector sum becomes non-zero. The device then trips the contact mechanism. In parallel, a thermal-magnetic trip unit provides protection against overload and short-circuit currents.
The combination of two protective functions in a single enclosure reduces panel space and wiring complexity. This is valuable in retrofit projects where distribution boards are already crowded.
Choosing the correct SWM6LS-125 model requires reviewing several technical parameters. The rated amperage (In) should match the load current, while the residual operating amperage must align with the protection strategy for direct or indirect contact. The rated volt-level and frequency must be compatible with the supply network. Also consider the short-circuit capacity, which is expressed in kA, to ensure the device can withstand the fault level at its location.
Discrimination and chooseivity are also important. In a distribution hierarchy, the SWM6LS-125 should coordinate with upstream and downstream protective devices to isolate only the faulty circuit. singielectric provides detailed time-amperage and residual amperage characteristic curves to assist engineers with this coordination study.
Conventional low-volt-level protection uses a separate residual amperage device (RCD) and miniature circuit breaker (MCB). The SWM6LS-125 integrates both functions, which simplifies installation and reduces the risk of wiring errors. The table below highlights the key differences:
| Feature | SWM6LS-125 RCBO | Separate RCD + MCB |
|---|---|---|
| Enclosure space | One module | Two modules |
| Wiring connections | Fewer terminals | More connections, higher risk of loose wiring |
| Residual amperage detection | Integrated | External RCD |
| Overamperage protection | Integrated thermal-magnetic | External MCB |
| Testing and maintenance | Single device test | Two devices to verify |
For new installations, the SWM6LS-125 reduces assembly time and improves reliability. For existing panels, replacing separate devices with an RCBO can free up space for additional circuits.
The SWM6LS-125 is designed to comply with internationally recognized standards for residual amperage and overamperage protection. Compliance gives engineers confidence in its safety and performance.
These standards define test procedures for tripping characteristics, endurance, residual amperage sensitivity, and short-circuit performance. The singielectric SWM6LS-125 series is tested in accordance with these frameworks to support project documentation and safety inspections.
singielectric is a manufacturer that focuses on low-volt-level protection components. The SWM6LS-125 Residual Amperage Operated Circuit Breaker is part of a broader range of DIN-rail devices. Buyers benefit from consistent quality control, clear technical documentation, and responsive after-sales support. For OEM and project-based procurement, singielectric offers customization options such as different rated residual currents, trip curves, and terminal configurations.
Engineers and procurement teams looking for a reliable RCBO for main distribution or sub-distribution should assess the SWM6LS-125. The product page provides datasheets, dimension drawings, and approval certificates to simplify the specification process.
Q: Is the SWM6LS-125 suitable for both commercial and industrial projects?
Yes. With a 125 A frame size and high breaking capacity, the SWM6LS-125 fits main distribution boards in commercial buildings and industrial control panels where residual amperage protection and overamperage protection are both required.
Q: Can the SWM6LS-125 replace a separate RCD and MCB combination?
In most cases, yes. It combines both functions in one module, which saves space and reduces wiring complexity. Always verify that the electrical ratings and tripping characteristics match the original design.
Q: What does the “LS” designation in SWM6LS-125 mean?
The “LS” suffix indicates the series designation within the singielectric product range, distinguishing this RCBO from other frame sizes or trip classes. Check the datasheet for the exact meaning for the SWM6LS-125 series.
Q: How should the SWM6LS-125 be tested?
Common practice is to press the test button at least once every six months. For critical installations, more frequent testing may be required by local regulations. The test button verifies that the residual amperage sensing mechanism is operational.
Q: Does singielectric provide technical support for coordination studies?
Yes. Singielectric offers time-amperage curves, residual amperage characteristic curves, and application guidance to help engineers achieve proper discrimination and chooseivity with the SWM6LS-125.
Specify the SWM6LS-125 for your next low-volt-level distribution project.
Visit the SWM6LS-125 Residual Amperage Operated Circuit Breaker product page for datasheets, certification documents, and ordering information.
[1] GB/T 6829-2017. Residual amperage operated circuit-breakers with or without overamperage protection for household and similar uses (RCBOs) [S]. 2017.
[2] IEC 60898-1. Electrical accessories - Circuit-breakers for overamperage protection for household and similar installations - Part 1: Circuit-breakers for a.c. Operation [S]. 2019.
[3] Wang Jianjun, Liu Zhigang. Research on the application of nanocrystalline arc-extinguishing grid in amperage limiting technology of low-volt-level circuit breaker [J]. Low Volt-level Apparatus, 2023, (5): 45-52.
