Possibility for portable battery-powered Ceramic Metal Halide fixture

[Dr. Mario]

I still have the Cyclops Thor Colossus Halogen spotlight for six years, and it originally have the 35 Watts automotive metal halide headlight kit installed in place of the original 130 Watts Halogen bulb, which some of you already knew - I decided to modify the spotlight once again to install the G8.5 HID bulb socket for the General Electric 39 Watts ceramic metal halide bulb I was curious if it works with the automotive digital inverter ballast (it works just fine, apparently - the ballast outputs squarewave AC output which is what the bulb wanted). Nice and BRIGHT. Had to wing the socket installation, as I decided not to mount the socket onto the reflector, which makes it hard to deal with the high voltage cable (which I stole off an automotive metal halide bulb), and ensure it's snug.

So, if you wanted to do it, just be sure it's compatible in term of wattage for both bulb and ballast (35 Watts automotive HID ballasts sometimes put out 39 Watts or more so I picked 39 Watts Ceramic Metal Halide bulb to work with the ballast already installed in the spotlight, which the bulb seems to be happy with), and the ballast also MUST output AC power, not DC - metal halide bulbs in general hates DC power which impact their lifespan. Preferably squarewave AC for most ceramic metal halide bulbs. And lastly I recommend to use the bulb in enclosed fixture in case the bulb decides to grenade.

TLDR; If you have been wondering if 35 to 39 Watts Ceramic Metal Halide bulb could function with the automotive inverter ballast, there you go - it works, but be sure it's compatible with each other in terms of wattage and power requirements.

 

[brickbat]

Will the automotive ballast hot-strike the GE CMH lamp?

 

[Dr. Mario]

If you mean older CMH bulbs, yes - hot restrike capabilities was hamstrung by the active antenna electrode in newer bulbs (the strip that looks like it's holding the bottom of arc tube - it's meant to generate UV light to kickstart it, it was actually blunting the ignition voltage down somehow so it was not able to hot restrike for some reason.)

So for newer bulbs, hot restrike is out but if you wait enough for the ceramic arc tube to be dark orangish-red hot or cherry red, you may be able to hot restrike it. Otherwise it just sits there flashing intense UV light that lights up the UV killer compounds in the Quartz envelope.

 

[Dr. Mario]

On the separate note, you have 20 kilovolts ignition voltage to kick start the older new stock CMH bulbs whose Krypton have decayed away. It would start it right up no problem.

 

[Dr. Mario]

Ordered the Osram Powerball Ceramic Metal Halide bulb to try out to see if spherical ceramic arc tube makes any difference for the reflector in the Cyclops Thor Colossus Halogen spotlight. At least I installed the G8.5 Halogen bulb socket meant for HID bulb (rated for the ignition voltage - apparently it's still enough to hold off the car HID ballast's ignition voltage as long as the bulb is still plugged in as electric charge usually tend to try and find the path of least resistance and obviously you want it to be the bulb), making it simple to pop off the reflector and swap the metal halide bulbs to test easily.

I also swapped Kensun ballast with Hylux A2088 HID ballast, and it's much better than the original ballast, no noticeable light drop-off that tends to happen with cheap inverter ballasts especially after warmup period is done, within a minute after ignition.

No wonder Big Bulbs trust Hylux, as it has the cleanest startup I have ever seen especially with a version of metal halide bulbs it's not really meant to be used with in typical application, however the ceramic metal halide bulbs actually lights up just fine on computerized inverter ballasts you get outta digital AC HID headlight kit, it has to be either 35 or 39 Watts CMH bulbs as they're compatible with the 35 Watts HID ballasts.

Just don't ignite it too often when hot, as it could cause the arc tube to blow out which usually happens with faulty igniter in the usual fixtures - I did it as an experiment to see how long it has to cool down before it finally lights up which is 10 seconds after shutdown. And yes, the bulb survived the ignition torture test (which apparently the bulb makers warn against) - I still have it, in the spotlight.

CMH bulb is worth it in my opinion, as it's a nice alternative for tint snobs who still want to find a solution for metal halide bulbs with poor CRI (CRI isn't always the automotive Xenon metal halide bulbs' strong suit, due to cost-cutting measures). At least it's as bright as the original Halogen bulb but lasts much longer than the original Halogen setup - especially with 3,000 Kelvins CMH bulb being nearly indistinguishable from the original Halogen bulb, they look almost the same as far as color tint goes.

 

[Dr. Mario]

Got the Sylvania / Osram Powerball ceramic metal halide bulb from Amazon in the mail, I immediately installed it in my modified Cyclops Thor Colossus spotlight, it surprisingly warmed up instantly (via Hylux 35 Watts A2088 conputerized inverter ballast which has expedited warmup feature), so I wonder if it has Xenon gas fill. It warmed up in like 1/3 - 1/2 the time General Electric ConstantColor ceramic metal halide bulbs spent on warmup period.

As for reflector, I am thinking Powerball ceramic metal halide bulb made a difference in term of light distribution within Cyclops Thor Colossus' reflector - which is a bit better than the tubular ceramic arc tube in the other bulbs. The arc tube in shape of American football ball, or just a proper ball, do make the difference for most reflectors. The reason I bought the Osram Powerball bulb was just to test my theory on the optical design and property within the spotlight itself.

 

[Dr. Mario]

And the ceramic arc tube shape apparently matters a lot - GE ConstantColor CMH bulb has a tubular ceramic arc tube (a bit like the usual high pressure Sodium bulb) which doesn't really favor some reflectors as you can see in the beamshot pictures below. I prefer the Osram Powerball CMH bulb more as it seems to do best job focusing the light more where I want the furthest reach.

BTW, in the shot, GE ConstantColor CMH bulb is rated for 4,200 Kelvins and Osram Powerball CMH is rated for 3,000 Kelvins - both bulbs have the same wattage rating since both 35 and, 39 watts metal halide bulbs are normally compatible with the 35 Watts automotive metal halide HID ballast.

 

[Dr. Mario]

FYI, 4,200 Kelvins Ceramic Metal Halide bulbs are apparently very hard to find, while I can easily find and buy 3,000 Kelvins CMH bulbs. I wonder why. 🤔

 

[Dr. Mario]

Apparently I am thinking that Powerball Ceramic Metal Halide bulb has a YAG ceramic arc tube - I decided to see if the bulb indeed has the UV killer dopants in the outer Quartz envelope (out of curiosity), which as you can see in the picture, the answer is an obvious yes.

However, I spotted the ceramic arc tube fluorescencing hot pink under the ultraviolet light (I used my Convoy S2 flashlight that I put together with Nichia NVSU233A-U365 LED - still have it). Any idea if I am right about it being made of YAG or is it made of something else? BTW, the ceramic arc tube in General Electric ConstantColor CMH bulbs do not fluorescence at all, except for the outer envelope.

*** EDITED *** Typo

 

[Dr. Mario]

IF anyone dare to use the same ceramic metal halide bulb setup in the Cyclops Thor Colossus Halogen spotlight as my spotlight or just a basis for any HID spotlights, please use quality AC ballast, preferably computer controlled internally, and Hylux A2088 is excellent and it lights up the 39 Watts Ceramic Metal Halide bulbs no problem since it basically met the requirements for the operation on electronic ballast (ie. LFSW - Low-frequency Squarewave AC power input for CMH bulb to operate and it also have bulb-out protection which is strongly recommended to lessen the chance of causing the ceramic arc tube in high hours CMH bulbs to blow up), here's a list of the CMH bulbs that I have used so far (I could update this list as time goes on, and when I get more different G8.5 / T4.5 CMH bulbs to test) basing on observation with the original Halogen reflector.

Thrower bulb(s):
39 Watts 3,000K Sylvania Osram Powerball CMH (MC39TC/U/G8.5/830)

Flood bulb(s):
39 Watts 4,200K GE ConstantColor CMH (CMH39TCU942/G8.5)
39 Watts 3,000K GE ConstantColor CMH (CMH39TCU830/G8.5)

***EDITED*** Typo

 

[Dr. Mario]

I think I figured out why the Osram Powerball ceramic metal halide bulb fluorescences hot pink under the Blacklight lamp, it turns out it's due to a particular salt used in the 3,000 Kelvins version (I wonder if it's the same for 4,200 Kelvins version), apparently.

 

[Dr. Mario]

I just discovered something about the Sylvania Osram Powerball CMH bulb that's in my spotlight; while General Electric ConstantColor CMH bulbs can't be hot restruck, this bulb restruck instantly, even with the ceramic arc tube still glowing red hot.

So, if you want to use ceramic metal halide bulb that can be immediately restarted with the electronic inverter ballast, Osram would be the best brand to use, especially Powerball CMH variety for the automotive HID ballast, like what I am currently using in my spotlight.

 

[Dr. Mario]

Final thing I want to add, regarding the ceramic metal halide bulbs with UV glow bottle starter inside, hot restrike feature may not work with car headlight HID inverter ballast due to DC current used during ignition and warmup in a particular polarity in the socket, so you may want to flip the bulb or high voltage wires over so the glow bottle starter's center electrode is connected to the positive terminal of the ballast igniter itself, just so it can flash over and forcibly reignite the hot bulb. And of course, make sure the 12 Volts DC ballast is designed to run the AC metal halide bulbs used in the car headlight as pretty much all metal halide bulbs do not like DC current after warmup (it's tolerated during warmup somewhat).

And I included a picture of the non-Powerball version of Osram ceramic metal halide bulb with the glow bottle starter inside, with the polarity labeled for ease of hot restrike on inverter ballast if you are to attempt that, observe how the glow bottle starter is connected to the prongs and the arc tube inside.

EDITED: corrected info