HID Kits and Halogen Bulbs

What is the difference between Xenon/HID Kit and conventional halogen systems?
HID Kits use different principles in the creation of light than halogen. HID bulbs contain a small capsule with a mixture of xenon gas and halide salts that aid in the creation of a powerful light source that is generally 3 times brighter than halogen bulbs. Halogen bulbs use a filament that creates light from basic ohmic resistance across a filament. While halogen bulbs runs directly from the cars 12V system, HID bulbs require a ballast that can supply accurate high voltage.
What can I gain from having HID in low beams, compared to halogen?
Having HID bulbs in low beams is widely used. Having a slow turn on HID bulb in a low beam application is no downside. It is solved by having the low beams come on right after engine is started, and they cannot be turned off before you switch ignition off. In general, there are only advantages to HID Kits.
What can I gain from having HID in high beams in a traditional open reflector based system, compared to halogen?
1. HID bulbs do not achieve full brightness until the metallic salts in the HID capsule are completely vaporized, which could take up to a minute (or more) on some setups.
This means they would not be much good for “flash to pass” signaling or extra light on demand.
2. Decreased bulb life if turning HIDs off and back on again. Continuous use in traffic passing situations would mean many hot re-strikes of HID arc, which shortens HID capsule life and requires MORE startup current than a cold capsule, thereby putting added wear & tear on your wiring and switching components.
3. Higher price. HID based systems costs more.
However with bi-xenon HID Kits, the high/low is accomplished thru a mechanical moving shield and/or moving reflector, and the actual HID capsule remains constantly on, with no warm-up or hot re-strike required.
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