Noark Electric Power Factor Correction Panel (APFC)

The Noark Electric Power Factor Correction Panel (APFC) is an IEC 61439-2 compliant low-voltage assembly engineered for automatic reactive power compensation in industrial, commercial and utility-connected installations. These APFC assemblies combine Noark Electric's Ex9 series moulded-case circuit breakers (MCCBs) and Ex9C heavy-duty contactors with application-specific accessories such as detuned reactors (5.67%–14%), capacitor fuses per IEC 60831, pre-charge resistors and surge protection devices. Typical factory configurations provide 6–14 capacitor steps, target power factor 0.95–0.99 and rated bus currents up to 800 A (panel typical); Ex9 breakers themselves are available up to 1 600 A for bespoke switchboard designs. Design and verification follow IEC 61439-1/2 requirements for temperature rise, dielectric properties, clearances/creepage and short-circuit withstand. Panels are factory type-tested or verified by calculation per clause 10 and supplied with routine tests (continuity, insulation, functional). Depending on busbar and breaker selection, verified short-circuit withstands can reach industry-standard levels (typical 50 kA sym / 65 kA peak) when coordinated with Ex9 breaking capacities and appropriate busbar cross-sections. Forms of separation (Form 1 through Form 4b per IEC 61439) are selectable: Form 2 or 3a is common for compact APFC units; Form 3b/4b is used where segregated capacitor compartments and separate withdrawal units improve serviceability and arc-mitigation. Harmonic-rich environments demand detuned or tuned filter strategies. Noark APFC panels implement 5.67% detuned reactors to shift resonance away from dominant 3rd/5th/7th components, reducing capacitor overcurrent and extending service life. Where higher harmonic distortion exists, stepped tuned filters or active filtering integrated with the APFC controller (Modbus/Profibus options) may be specified. The Ex9C contactors include built-in pre-charge resistor circuits and are specified for frequent switching of capacitive loads; capacitor fuses compliant with IEC 60831 provide selective protection and facilitate safe capacitor replacement. Integration and competitive positioning: Noark APFC assemblies can be deployed as standalone cabinets or integrated into larger switchgear lines alongside Siemens SIVACON, ABB MNS, or Schneider Prisma Set concepts for unified distribution strategies. For hazardous areas, components and enclosure options can be selected to meet IEC 60079 requirements. Standard IP ratings for indoor APFC cabinets are IP31–IP42; higher ingress protection and acoustic segregation for transformer rooms are available as options. Typical applications include large motor plants, HVAC banks in commercial buildings, data centres and utilities seeking to avoid PF penalties while maintaining compliance with IEC and IEEE harmonics guidance.