Heavy Duty Capacitors are robust, industrial-grade components designed to handle high electrical, thermal, and mechanical stress. These capacitors are ideal for applications that demand long operational life, high current capacity, and exceptional reliability, such as power factor correction, motor start/run functions, and energy systems in challenging environments. Neptune is a leading manufacturer of Heavy Duty Capacitors, including the advanced POWER-9 series, engineered specifically for static power factor correction of motors and transformers. The POWER-9 series features a unique internal design with three capacitor elements connected in a delta configuration, enhancing performance and reliability.

These capacitors incorporate a high-precision overpressure protection system that ensures superior ground safety and mitigates the risk of arcing—even in high energy density environments. The resin-impregnated design of the heavy-duty series ensures excellent insulation and mechanical strength. Each capacitor element is first impregnated and visually inspected before being housed in a durable plastic container, guaranteeing uniform resin distribution and consistent quality. With advanced design and stringent manufacturing processes, Neptune's heavy duty capacitors deliver unmatched performance and durability in demanding industrial applications.


The capacitors making up the POWER-9 series Heavy Duty Capacitor are used for static power factor correction of a wide range of motors and transformers. This series share the same internal configuration, with three capacitor elements wired internally in a delta connection. The overpressure protection system is specifically dimensioned so as to constantly ensure maximum safety in terms of ground protection and protection against the risk of arcing, even in conditions where there is a high energy density.

In these series HEAVY DUTY of resin-impregnated capacitors, the three elements are housed in a plastic container which, together with the impregnating agents, assures dual insulation between the wound cores and metal enclosure. To guarantee perfect filling during the resin impregnation process, the process itself is carried out prior to the elements being placed in the enclosure; in this way the distribution and uniformity of the impregnation can be subjected to a complete visual and dimensional inspection.