2 Compatible Devices2.3.1 Molded-case Circuit Breakers, Ground Fault Detectors, and Magnetic Contactors2-202.3 Peripheral Devices2.3.1 Molded-case Circuit Breakers, Ground Fault Detectors, and MagneticContactorsAlways install a circuit breaker to protect the main circuits. The type of circuit breaker that is required dependson what you need to detect.Detecting only overcurrent: Use a molded-case circuit breaker.Detecting overcurrent and leakage current: Use a ground fault detector that detects overloads and leakage cur-rent. Or, use a molded-case circuit breaker together with a groundfault detector that detects only leakage current.(1) Molded-case Circuit BreakerA molded-case circuit breaker shuts OFF the power supply when it detects an overcurrent. Install a molded-case circuit breaker between the power supply and the main circuit power supply input terminals (R/L1, S/L2,and T/L3).Select the molded-case circuit breaker based on the information in (4) Converter Input Current and InrushCurrent.(2) Ground Fault DetectorA ground fault detector detects leakage current. Some models will also detect overcurrent in addition to leak-age current. Use the type that is suitable for your application. Install a ground fault detector between the powersupply and the main circuit power supply input terminals (R/L1, S/L2, and T/L3).Recommended ground fault detector: A ground fault detector with harmonic countermeasures and a ratedsensed current of 30 mA or higher for each power regeneration con-verter. A ground fault detector with harmonic countermeasures removesleakage current for harmonics and detects only leakage current in thefrequency range that presents a hazard to humans. If you use a groundfault breaker that does not have harmonic countermeasures, the leakagecurrent from the harmonics will increase the chance of malfunctions.Select the ground fault detector based on the information in (4) Converter Input Current and Inrush Current.(3) Magnetic ContactorsThe magnetic contactor for the control circuit power supply turns the control circuit power supply ON andOFF. The magnetic contactor for the main circuit power supply turns the main circuit power supply ON andOFF. Use a magnetic contactor (MC) to turn OFF the control power supply or main circuit power supplysequence.Note: If the magnetic contactor on the main circuit power supply input is turned ON and OFF frequently, the Σ-V-SD servodriver may be damaged. Do not turn the power supply ON and OFF with the magnetic contactor more than one timeevery 30 minutes.Select the magnetic contactor based on the information in (4) Converter Input Current and Inrush Current.WARNING• Always install a molded-case circuit breaker or ground fault detector in the main circuit.Failure to observe this warning may result in electric shock, equipment damage, or fire.
