The Siemens 5SV3745-6 is a 4-pole residual current operated circuit breaker (RCCB) from the RCCBs family, Type A, rated at 125 A with a 500 mA residual trip threshold and a nominal AC voltage of 400 V. Type A detection means it responds to sinusoidal AC residual currents plus pulsating DC residuals up to 6 mA — the standard choice for circuits feeding single-phase rectified loads like switching power supplies, variable-speed drives, and IT equipment where pure AC-only (Type AC) devices would be blind to the DC component. The 125 A rating and 4-pole (3-phase + neutral) configuration size it for main incomer or large sub-distribution boards in commercial and industrial panels, typically on a DIN-rail mount inside a distribution enclosure.
Compliance and documentation
Export control classification is AL: N / ECCN: EAR99, no special licensing required for most destinations. Packaged as a single piece (1 unit), dimensions 78 x 97 x 85 mm.