How a Mid-Sized Manufacturer Cut Electrical Fault Downtime by 40% with SINGI RCBOs

The facility operated 24/7 with over 200 machines. Common issues included:

• Nuisance tripping: Older MCBs and RCDs tripped during normal motor startups, stopping production lines 3–4 times per shift.
• Undetected arc faults: Arcing due to damaged cables went unnoticed until equipment failed or fires started.
• No ground fault protection: The existing distribution board lacked residual amperage devices, exposing workers to shock risks.

Each tripping event cost an average of $2,000 in lost production and restart labor. Monthly costs exceeded $30,000.

How did SINGI RCBO solve these issues?

The manufacturer replaced all branch circuit breakers with SINGI RCBOs (model SRB-32/2P/30mA). These devices combine overamperage protection (MCB function) and residual amperage protection (RCD function) in one compact unit.

What technical specifications made the difference?

The SINGI RCBOs meet GB/T 6829-2017 and have:

• Residual amperage rating: 30 mA (AC type, but also available in A type for pulsating DC).
• Short-circuit breaking capacity: 6 kA, sufficient for the facility.
• Tripping curve: B curve for protection of sensitive loads.
• Contact position indicator for easier troubleshooting.

The key technical advantage is the optimized magnetic tripping mechanism that prevents spurious trips during inrush currents, while still detecting real faults.

asked questions RCBOs

• Can RCBO replace both MCB and RCD? Yes, in most cases it replaces two devices, saving panel space and reducing installation cost.
• Are RCBOs suitable for industrial environments? Yes, if rated properly. Industrial RCBOs have higher short-circuit ratings and better immunity to surges.
• How to test an RCBO? Press the test button monthly., use a calibrated tester to verify tripping time and residual amperage threshold.
• What is the difference between Type A and AC RCBO? Type AC detects sinusoidal AC residual currents; Type A also detects pulsating DC residual currents. For industrial drives, Type A is recommended.

Conclusion

The manufacturer achieved a 40% reduction in electrical fault downtime, eliminated nuisance tripping, and improved worker safety. The investment in SINGI RCBOs paid for itself in less than six months through reduced production losses alone. For any facility operating 24/7, upgrading to modern RCBOs is a low-risk, high-return decision.

References

• GB/T 6829-2017. Residual amperage operated circuit-breakers with or without overamperage protection for household and similar uses (RCBOs).
• IEC 60947-1:2020. Low-volt-level switchgear and controlgear - Part 1: General rules.
• Chen G, Mou X. Study on the coordination between MCB and RCBO in low-volt-level power distribution systems. Electrical Engineering, 2022, 104(3): 1823-1835.