Build your own HID-Ballast

[li_gangyi]

does it take the place of the starter (ignitor)?? And will it work with floursent tubes?? Seems pretty cool to have an electronic ignitor (no more flickering)

[mathias]

Yes, it replaces the "glow-tube starter". I have only tested this with the HID-lamp, this design is the same they use in factory-made HID-Ignitors, and I don´t know if it works with fluorescent tubes. But be careful it puts out 3000-4000 Volt in the starting sequence.

[li_gangyi]

so how can I actually drop the starting voltage to arund 300-400 V??

[mathias]

Why do you want to drop the voltage to 300-400V ? A fluorescent tube needs 500-1000V to start. And if you want an electronic starter for fluorescent tubes, you can buy that in a normal lamp shop. But if you absolutly want to drop the voltage in the above circuit just remove 2 or 3 of the 100nF caps.

[li_gangyi]

sorry...forgot it needs 1kV...his original circuit will proved arund 3-4KV...which will kill me tube I guess...so I just have to remove 1 100nF cap huh?? seems good to me...I can't find the electronic starter arund here...hmmm wonder why...but they are so ex...even if I can locate one...I'll give this circuit a go and see what happens...hehehe

[mathias]

I´m working on a new lightengine and while I was testing it, the bulb was overheated and turned it self of. The problem was that the electronic ignator was dead after that. So I just want to warn you. Do not try to start the bulb when it´s hot, wait 15 minutes, before you turn it on again, and there will not be any problem with the ignator.

[li_gangyi]

how did it kill itself?? I used it on my flourscent lights...works good...

[Khmann002]

How is this project coming along? Has anyone have any improvments?

[mathias]

I wrote before that the bulb was overheated and turned it self of. It wasn´t because of my new lightengine. It turned it self of again after 5 minutes in my normal ohp-setup. So I measured the voltage over the bulb and it was over 115 Volt, normally it should be 96 Volt. The bulb has changed it´s voltage-characteristic when it has been "burned in", and the ballast feeds it with to much voltage right now. I tested to only use 3 of the 36W ballasts, and the bulb worked perfectly again but it will only get 114W. I´m going to reduce the power from the fourth 36W ballast tomorrow, so the bulb will not get overheated.
For whose of you who want to build this ballastdesign, use four 30W ballasts instead of 36W and you will not get any problem with overheated bulbs.

I have updated the electronic ignator, it will work better now.

[mathias]

I have now done some more testing and measuring on the bulb and ballasts. A new design can´t be perfect from the beginning it always need some adjustment. To get as close as possible to the rated 150W power, I need to mix 30W and 36W ballasts, two 30W and two 36W, now I got exactly 150W with 230V main voltage. The bulb works perfectly and is not overheated any more. Please let me know if you have problem with this design.