Lighting Capacitors

Lighting capacitors regulate power and correct the power factor in lighting circuits, reducing energy use and stabilizing voltage. They support fluorescent ballasts and high-intensity discharge (HID) lamps (including mercury vapor, metal halide, and high-pressure sodium) for commercial, industrial, and residential fixtures, delivering reliable, flicker-free startup and longer fixture life.

In parallel compensation the capacitor is wired across the supply to correct the overall power factor of the circuit.

In series compensation it is placed in series with the lamp to help control lamp current and starting characteristics. Motor Capacitors’ CBB66A lighting capacitors are designed to support both configurations depending on the ballast design.

It depends on the series. Motor Capacitors’ dry-type lighting capacitors are built for prolonged operation at temperatures up to 105°C, making them well suited to the heat inside enclosed fixtures and ballast compartments, and are manufactured to a standard capacitance tolerance of ±3% (±5% and ±10% available on request). Motor Capacitors’ oil-filled CBB66A lighting capacitors are rated for -40°C to +100°C with full rated 60 Hz voltage applied.

The right capacitor type depends on your installation requirements. Dry-fill construction eliminates the risk of oil leaks, keeps the units lighter and more compact, and, combined with the 105°C rating, makes the dry-type series dependable for ballast and HID lamp service. The oil-filled CBB66A series is UL approved, protected by a 10,000 AFC safety pressure interrupter, and supports both series and parallel ballast compensation.

By correcting the power factor of the ballast, lighting capacitors reduce the current the circuit draws, which lowers energy losses and can reduce demand charges. They also help stabilize voltage, which supports reliable startup, flicker-free operation, and extended fixture lifespan.