China manufacturer of magnetic ballasts for metal halide flood lights & hps flood lights

Capacitors are optional for Reactor (R) and High Reactance (HX) ballast circuit designs. The optional capacitor is used for power factor correction only and does not affect the ballast or lamp operation. The capacitor, when added, will reduce the ballast input current while the HID lamp is operating. However, the optional capacitor increases the ballast input current requirement to level greater than the normal operating current during open circuit condition that occur when attempting a hot re-strike of a hot HID lamp after a momentary power loss or shut off.