Vfd

Product Details

When using the earth leakage current breaker with the inverter circuit, select its rated sensitivity current as follows, independently of the PWM carrier frequency. Example (Note) 1 Install the earth leakage breaker (ELB) on the input side of the inverter. 2 In the connection earthed-neutral system, the sensitivity current is blunt against an earth (ground) fault in the inverter output side. Earthing (Grounding) must conform to the requirements of national and local safety regulations and electrical codes. (NEC section 250, IEC 536 class 1 and other applicable standards) Selection example (in the case of the above figure (400V class connection))  Breaker designed for harmonic and surge suppression Rated sensitivity current In10(Ig1+Ign+Igi+Ig2+Igm)  Standard breaker Rated sensitivity current In10{Ig1+Ign+Igi+3X(Ig2+Igm)} Ig1, Ig2: Leakage currents in wire path during commercial power supply operation Ign : Leakage current of inverter input side noise filter Igm : Leakage current of motor during commercial power supply operation Igi : Leakage current of inverter unit (200V 60Hz) (200V 60Hz) 0 20 40 60 80 100 120 2 3.5 5.5 8 1422 30 38 60 80 100 150 Motor capacity (kW) Example of leakage current of cable path per 1km during the commercial power supply operation when the CV cable is routed in metal conduit Example of leakage current of three-phase induction motor during the commercial power supply operation Leakage currents (mA) Leakage currents (mA) Cable size (mm2 ) 0.1 0.2 0.4 0.75 1.5 2.2 3.7 5.5 11 7.5 20 15 0.02 0.03 0.05 0.07 0.1 0.2 0.3 0.5 0.7 1.0 0 20 40 60 80 100 120 2 3.5 5.5 8 1422 30 38 60 80 100 150 0. 1 0. 2 0. 3 0. 5 0. 7 1. 0 2. 0 1.5 3.7 2.2 7.5 15 5.5 11 20 Motor capacity (kW) For " " connection, the amount of leakage current is appox.1/3 of the above value. (Three-phase three-wire delta connection 400V60Hz) Example of leakage current per 1km during the commercial power supply operation when the CV cable is routed in metal conduit Example of leakage current of threephase induction motor during the commercial power supply operation (Totally-enclosed fan-cooled type motor 400V