The hid ballast has to be able to regulate the current in your hid lighting system very precisely.
Hid bulb ballast.
You won t find the same type of circuitry in other vehicle lights.
Too much power and your lamp will die out faster and may actually explode.
The hid ballast has special circuitry installed that helps restart the lamp quickly after turning it off.
Hid lamps require a ballast to operate.
If you do not use the ballast there will be nothing to regulate the electrical power and the bulb may use more energy and burn out quickly.
Too little power isn t good for a hid lamp either as it can damage the light causing uneven lighting and a possible crack in the arc inside the bulb.
Hid lamps take several minutes to warm up.
Here is an ebay aftermarket 10000k 75w automotive xenon hid lamp running on a us 70w m98 psmh ballast without the usual 3 wire ignitor wired to the ballast circuit.
Full light output is reached after the arc tube temperature rises and the metal vapors reach final operating pressure.
This is because the xenon gas inside the bulb needs time to cool down before it starts receiving a strong high voltage current again that turns the light back on.
Hids lights must be capable of turning on and off quickly in order to function without overheating.
Instead i started this bulb using a special matsushita super high voltage ignitor for an acura tl car from about 1999 that is wired to a e26 socket pigtail commonly used in led.
In order to sustain this brightness an hid bulb ballast must be used to regulate its voltage.
Hid ballasts also act as dc to ac converters.
Typically the hid ballast sometimes with the addition of a capacitor and igniter serves to start and operate the lamp in a controlled manner.