Cold Cathode ?s

[tech_wiz19]

Hi guys, I'm new here. I have some questions that aren't directly related to PC technology. I'm trying to get some answers and info about cold cathode lighting and since I know it is regularly used in case mods I thought some members here might be able to help me out. I'm planning on using a 6-8 inch CCFL tube in a very unique application in which it would need to be powered by a very small, lightweight, rechargeable battery. From what I have learned so far CCFL requires 12v so I searched the web and found these:

http://www.panasonic.com/industrial/battery/oem/chem/lithion/

If I combined three of them then it would be just under 12v, with a max of 2000mAH. I read somewhere that cold cathode lights require between 120 and 300mAH, so at 120mAH the battery should last over 16 hours, does this sound right? Also, correct me if I’m wrong, but I'm assuming that the inverter simply converts power from AC to DC or boosts the DC voltage from the power supply to 12v, and won't be necessary for my application, since there won't be any room for it. Let me know what you guys think of this setup; if there are any problems with it, how it can be improved, etc. I don't know that much about electricity and batteries and even less about CCFL so if anyone has some info or ideas about what batteries to use, or knows of some good sites about this stuff then please let me know. Any info will be much appreciated, thanks!

[mattg2k4]

Your math is correct for the maximum run time, assuming a cc uses 120ma.

The inverter turns the 12v dc input into several hundred volts of ac and is quite necesary if you want to run it from a 12v input. Most cc inverters I've heard people testing out can run with as low as 6v input and still output a sufficient voltage, but your mileage may vary.

[tech_wiz19]

Thanks for clearing up the purpose of an inverter, I did a search and found a couple of very small inverters that will probably fit my application. Let me know what you think of them or if you recommend one.

http://www.elwirecheap.com/12voltinverter.html
http://www.frozencpu.com/cgi-bin/frozencpu/lit-17.html

[tech_wiz19]

One more question: will the presense of an inverter drain my batteries faster?

[mattg2k4]

I would get the one from frozen cpu, as it has a connector for standard cold cathode plugs.

Faster than what? All cc's require the use of an inverter if you have only 12v input, so I don't know what you're comparing it to.

[tech_wiz19]

Bear with me I don't know that much about electricity, but if you recall my calculation earlier in which, if a 2000 milliamp battery was powering a CC that consumed 120mAH, the battery should last over 16 hours. But that was before I knew that an inverter was necessary and I thought I could run a CC directly off of a 12v source. I've learned that voltage and current have a direct relationship and I guess I'm just having a hard time understanding how a 600v+ CC is going to consume only 120mAH. Is that a normal consumption rate for something with such a high voltage? I'm just a little confused, I don't uderstand when you start off with a 12v power source how it can be boosted to 600v+ instantaneously.

[FLG]

It gets stepped up by the inverter, so a 12v battery before the inverter will/should work, take your tv for example it takes 110v from your wall outlet and after the voltage has been stepped up by different components, on the other side of that screen is roughly 40,000 volts!

[tech_wiz19]

I understand that the inverter steps up the voltage, but what I want to know is approximately how many mAH a 6 in. CC + inverter will be drawning from my batteries so I will know how long I should expect my batteries to last and whether or not this setup is going to be efficient. This page (http://www.lighting-inc.com/manufacturers/nationalcathode/whatis.html) says that a CC consumes between 120 and 300mAH but it is very vague. Does this sound right to you? I'm planning on making a custom battery pack with either three or four panasonic (http://www.panasonic.com/industrial/battery/oem/chem/lithion/) lithium-ion AA batteries, which would make the voltage either 10.8 or 14.4. However I don't know if the inverter will accept anything besides 12v exactly. I know theoretically 14.4v will make it a little more efficient and 10.8v requires one less battery making the pack lighter and smaller, but like I said I don't know if the inverter will accept either of these voltages. Does the inverter have a regulator which won't allow it to recieve any more than 12v DC? Will it work properly with less than 12v? If both voltages will work, which one would be best?