LS Electric Variable Frequency Drive (VFD) Panel

The LS Electric Variable Frequency Drive (VFD) Panel is an IEC 61439-compliant low-voltage assembly engineered to integrate LS Electric iS7 VFDs with Susol and Metasol moulded-case circuit breakers (MCCBs) and MC contactors to deliver robust motor control from 0.75–1000 kW at 380–690 V AC. Typical factory-built configurations include input protection (Susol/Metasol MCCBs, RCCB options), line reactors or multi-pulse (6/12/18-pulse) and active front-end (AFE) rectifiers for harmonic mitigation, integrated EMC filters rated C1/C2/C3 per IEC 61800-3, dU/dt or sinusoidal output filters for long motor cable runs, and hard or soft bypass arrangements for serviceability. The iS7 family provides vector and flux-vector control, STO (Safe Torque Off) certified to IEC 61800-5-2, network options (EtherNet/IP, Profinet, Modbus) and regenerative/AFE variants for energy recovery applications. Panel mechanical design follows IEC 61439-1/-2 requirements for dielectric, thermal, and short-circuit verification with selectable forms of separation (Form 2b, Form 3b or Form 4a recommended for drive panels) to segregate power, control, and auxiliary circuits and to permit safe live-work procedures. Enclosure IP ratings from IP31 to IP54 are standard; IP55/IP66 and Ex-rated enclosures are available for aggressive environments with compliance to IEC 60079 where hazardous-area certification is required. Short-circuit withstand and fault level coordination are achieved by combining Susol/Metasol MCCBs with documented Icu/Ics per IEC 60947-2 and specifying switchgear assembly Icw/Ipk values (panel type tested to rated short-circuit up to project-specific values, commonly 25–65 kA depending on busbar and breaker selection). Drive-panel protections include thermal monitoring, overcurrent/inrush limiters, ground-fault protection, and optional motor protection relays. Auxiliary components such as MC contactors are used for bypass and soft-start configurations; all installed switching devices comply with IEC 60947. For systems requiring system-level benchmarking, LS Electric-based assemblies are comparable to Siemens SIVACON, ABB MNS and Schneider Prisma Set in modularity and serviceability but provide a cost-competitive alternative with LS component availability. Typical applications: HVAC central plants, pump and fan skids, conveyors and crushers in mining and cement, marine propulsion auxiliaries, and process drives in petrochemical and wastewater facilities. Engineering deliverables include short-circuit studies, harmonic studies (IEEE 519 guidance), cable sizing, fault-level-rated busbar layouts, and factory FAT with witness testing to IEC 61439-1/2/3/6 as required. For turnkey panels, contact our engineering team for site-specific specification, LV distribution coordination, and quote.