Is it possible to parallel two HID ballast?

[ma_sha1]

What if wire two 35W HID slim ballast in parallel connect to one igniter one lamp?

would that make a 70W HID?

[XeRay]

What if wire two 35W HID slim ballast in parallel connect to one igniter one lamp?

would that make a 70W HID?

No you cannot do that.

[ma_sha1]

Thanks, can you explain the reasons?

[richardcpf]

It is possible but that would damage/greatly shorten the life of the ballast and bulb, because the supplied voltage is not always constant. dont know if that would make it 70w bright...

[jh333233]

If i get 2 li-ion cell in parallel to push 1 lamp,is it ok?
No, it will get over drived by the current
or even it dont get burn, over driving will GREATLY decrease the lifetime

1 ballast is danger enough
2 in parallel, not to think

[XeRay]

Thanks, can you explain the reasons?

The ballast is not a passive device, it is an active device which maintains constant power. 2 ballasts together would create chaos.

[lucca brassi]

The ballast is not a passive device, it is an active device which maintains constant power. 2 ballasts together would create chaos.

Nice explanation!

Well problem is that ballast AC (voltage go through O from +95V to - 95V ) or DC ( is for lower power normaly for example 24W HID from +65V to O and back ) at frequency cca 250 Hz .
You must sychronize frequencies at the same clock , otherwise for example if one balast is on +95V and other on -95V result is zero
Simpler is to have one ballast but you doubled power IGBT transistors conected in H bridge or switch them for more powerfull. You must also sychornize ignition period which is harder because new ballast are normaly digital (and you can do that ) old are analog resonant btw , but ignitior is still analog made from coil winded like autotransformer and powerfull capacitor which stores energy and that part must be literaly equal . That on short
if you want more you can read for example about electronics

http://focus.ti.com/lit/ds/slusa23/slusa23.pdf

[richardcpf]

Well problem is that ballast AC (voltage go through O from +95V to - 95V ) or DC ( is for lower power normaly for example 24W HID from +65V to O and back ) at frequency cca 250 Hz .
You must sychronize frequencies at the same clock , otherwise for example if one balast is on +95V and other on -95V result is zero
Simpler is to have one ballast but you doubled power IGBT transistors conected in H bridge or switch them for more powerfull. You must also sychornize ignition period which is harder because new ballast are normaly digital (and you can do that ) old are analog resonant btw , but ignitior is still analog made from coil winded like autotransformer and powerfull capacitor which stores energy and that part must be literaly equal . That on short .

No one would believe this was quoted from a flashlight forum.

[lucca brassi]

so ... what is not correct ?

[jh333233]

It is not the problem of the net voltage
it should be the stability of the current
you will have to maintain the stable arc

[ma_sha1]

By far the best explanation, still not based on facts but it's got some good logics.

The way I see it, short of actually doing it & see, there are possibly three outcomes (Parallel ballast only, use one Igniter)

1, Two Ballast exactly in sync. So they go positive & negative together, end up with 2x AMP, 2x Power.

2, They are in Sync negatively, I.E. +95 & -95 always cancel each other
Net result, no power, nothing lit up

3, They are completely out of Syn. I.E, each ballast powering the lamp at
different times. Because the +95 & -95 are applied at different clock, they do not cancel each other. Because no cancellation effect, it'll still be 2x the AMP & 2x the power

Think about PWM dimming (reduce power), except that this is like PWM boosting to increase power.

Looks like there still a good chance this might work,
now just a matter of who wants to try it first?

Because the two ballasts from a kit will operate by the same frequency,
they could only be either in Sync. ( positively or negatively) or Out of Sync.,
Not possible to be a chaos, ie. some times in Sync & some times out of Sync. They are either in our out of Sync completely.

Nice explanation!

Well problem is that ballast AC (voltage go through O from +95V to - 95V ) or DC ( is for lower power normaly for example 24W HID from +65V to O and back ) at frequency cca 250 Hz .
You must sychronize frequencies at the same clock , otherwise for example if one balast is on +95V and other on -95V result is zero
Simpler is to have one ballast but you doubled power IGBT transistors conected in H bridge or switch them for more powerfull. You must also sychornize ignition period which is harder because new ballast are normaly digital (and you can do that ) old are analog resonant btw , but ignitior is still analog made from coil winded like autotransformer and powerfull capacitor which stores energy and that part must be literaly equal . That on short
if you want more you can read for example about electronics

http://focus.ti.com/lit/ds/slusa23/slusa23.pdf

[HKJ]

2, They are in Sync negatively, I.E. +95 & -95 always cancel each other
Net result, no power, nothing lit up

No, the 2xXX watt will not just disappear, probably the ballast will lit up!

Because the two ballasts from a kit will operate by the same frequency,
they could only be either in Sync. ( positively or negatively) or Out of Sync.,
Not possible to be a chaos, ie. some times in Sync & some times out of Sync. They are either in our out of Sync completely.

No, they will not operate at exactly the same frequency, there might easily be a few percent difference.

[get-lit]

There are special current regulating power supplies that are made to be capable of being paired up by synching their timings, but ballasts also have an ignition and boost phase, so I'm not sure how often you'd come across what you're looking for, if ever.

Also, be sure to never operate an HID ballast outside of it's documented methods. They are way too dangerous to mess around with. An acquaintance of mine was just killed by a similar device just a few days ago.

[ma_sha1]

Also, be sure to never operate an HID ballast outside of it's documented methods. They are way too dangerous to mess around with. An acquaintance of mine was just killed by a similar device just a few days ago.

Sorry to hear that, that's terrible news.

Although it's tempting, I am Not going to try it.

[Ra]

The ballast is not a passive device, it is an active device which maintains constant power. 2 ballasts together would create chaos.

No offence, but I'm a little surprised that this discussion is still going on..

No, I'm not going to say those three. very well known words.. (TJS..)

Ra.

[06yfz450ridr]

I know this thread is old but i stumbled across this. Supp there are 2 35w ballasts hooked to one bulb and you can clearly see and hear the two ballasts. Hopefully this is real

http://www.youtube.com/watch?v=Sag9L...e_gdata_player

[XeRay]

I know this thread is old but i stumbled across this. Supp there are 2 35w ballasts hooked to one bulb and you can clearly see and hear the two ballasts. Hopefully this is real

http://www.youtube.com/watch?v=Sag9L...e_gdata_player

Must have 2 stupid (rather than smart) ballasts.

[mvyrmnd]

I was hoping for a more classic YouTube video where it exploded violently

So it would appear that it can work, sometimes, maybe.

I wouldn't be brave enough to try it myself...

[ma_sha1]

Wow, didn't think this would really happen, the youtube guy got some big balls

[mvyrmnd]

The video ends after only a few seconds of runtime. Maybe it did explode and that was all the footage recoverable from his torched camcorder!

[XeRay]

They must be DC output ballasts for this to work, no way they are exactly synchronized if the were at 400 Hz or other AC frequency.