This may be a dumb question, but are car HID's considered to be Metal Halide lamps? I feel like I've asked this before, but as life happens, I tend to forget.

Of course, these are metal halide lamps by principle.

The main difference towards normal general lighting MH's is the requirement of instant sufficient light output. And that mandates the use of Xenon - a buffer gas that is able to emit significant light output before the halides evaporate. Even when that means the power to a 35W rated lamp has to be boosted to 70..90W for the first minute or so, because the Xenon discharge is way less efficient.

This is good to know. Another thing I've wondered... is it possible to run those kind of Metal Halide lamps on ballasts that use mains electricity?
It seems as if those kind of Metal Halide lamps are made specifically for vehicle use only, but I know I could be wrong about that.

You can power the automotive ballast from an external power supply

This is good to know. Another thing I've wondered... is it possible to run those kind of Metal Halide lamps on ballasts that use mains electricity?
It seems as if those kind of Metal Halide lamps are made specifically for vehicle use only, but I know I could be wrong about that.

They were. Because for general lighting they would be way too expensive, inefficient and short lived.

The automotive application has way more frequent starting, then there is the instant output requirement. Plus they need to be quite geometrically precise in the arc positioning.
These features cost a lot of money, lower efficacy and shorter life, but are not needed for general lighting.

On the other hand in car headlights they do not make that many total hours, so rated bulb life is in the 1000 hours ballpark is sufficient for car use, but totally unacceptable for general lighting use.


One consequence of the Xenon buffer gas is quite high ignition voltage, above what standard MH ballasts are not able to support. Dunno if the lamps with integrated ignitors (with superimposed igniotors in their base, like D1S) would work on a sinewave ballast OCV, there is a chance they will be actually able to work. But these weren't that common as the systems having ignitors within the ballasts.

So best way would be to really use the 12V DC power supply and then the original automotive ballast for them. Just make sure it is able to deliver at least 10A, at least for a short time, the ballasts tend to draw that power for the warmup boost function. Also don't forget the ballast efficiency during the boost does not have to be that great, so their input current at the 12V could really be in the 10A ballpark.
With most "aluminum brick" power supplies you may crank up the voltage by a trimpot (up to 16V at least), that way you get more power from them, as the overload protection uses to respond to output current and not the true power, but the HID ballast really draws the power, so at higher input voltage their input current will be lower.