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

A single coil choke can be used when the input voltage to a fixture meets the starting and operating voltage requirements of an HID lamp. In this situation, the reactor choke performs only the current-limiting functions since the voltage necessary to initiate the ignitor pulses, and start and sustain the lamp comes directly from the input voltage to the fixture. The reactor choke is electrically in series with the lamp. There is no capacitor involved with the operation of the lamp. Because of that, the lamp current crest factor is desirably low, in the 1.4 to 1.5 range.

Metal halide lamps use sodium in their arc tubes to give them comparatively high light output. The arc tubes also have other
metals or chemicals mixed with the sodium to balance and improve color. In fact, these lamps have become the standard for lighting sports for TV. Their lives are shorter than those of mercury lamps;but, they are significantly more efficient.High pressure sodium (HPS) lamps generate light with a sodium (primarily) arc discharge. This gives them the highest luminous efficacy (lumens of light per watt of energy used) of these three lamps (over twice that of mercury). Their average rated life is similar to that of mercury lamps.
All three HID lamps require supplemental electromagnetic and/or electronic circuitry (normally called a “ballast”) to start and stabilize the arc discharge and to condition the external power supply to the lamp's specific electrical requirements. The selection of a ballast type depends on where it is to be used. Mercury and metal halide lamps change little in operating characteristics over life and ballast operation remains fairly constant. But HPS lamps change operating
characteristics dynamically over life. Following is an explanation of general operating characteristics of HPS ballasts followed by a tabular listing of typical electrical data of different ballast wattages and types for all three HID lamps.