Pulse Start Metal Halide Ballasts. The pulse start metal halide ballasts are designed to work better in cooler temperatures or from greater distances from the light. The new generation of ballasts uses high starting voltages to power lamps, resulting in a higher lumen rating.
Pulse-start MH lamps do not have a starting probe electrode . Instead they have a high-voltage igniter that works with the ballast to start the lamp using a series of high-voltage pulses. Without the probe electrode, the amount of pinch area at the end of the arc tube is reduced, which results in a reduced heat loss.