| I have found some "old" flourescent lamp inverter. | HV output is cca 800V. | | First thing: | I have made small capacitor bank in which i want to store this HV output | voltage. | So, instead to go to lamp, the hv output is going to capacitor bank. | | How to make this ?
Then perhaps you would explain why you are asking this.
For all I know, you are some 10 year old wanting to electrocute his kid sister.
Very high voltages are not automatically dangerous. Capacitors are not automatically dangerous. But very high voltages combined with capacitors invariably are dangerous. The combination doesn't have that many practical uses.
It may be that the lamp inverter will not be able to provide the output necessary to charge a cap. The high voltage put out by a lamp ballast (inverter) is intended to provide a very small charge at a high voltage sufficient to trigger the lamp by ionizing the gas within. When lamp current begins to flow, the output voltage will drop significantly.
A capacitor will appear to be a dead short across the ballast output. While the ballast will operate in constant current mode, its I-V characteristic may prevent it from generating anything near the triggering voltage you are observing.
By the way, the ballast output is AC, so that will present its own problems with charging a cap.
-------------- Thank you Paul for your answer. I am aware of everything you have written and thats why i need your ideas. I can not write down what is the totaly end result but i can write this. There are two options for me:
To get high AC current ( 120V~5A ) -- first option
1.) to convert this direct output from lamp inverter ** ( i will never reach
To get high AC current ( 120V~5A ) -- second option
2.) to convert HV to DC and to save this DC to capacitor bank and then to use DC/AC converter
In the second part i have to use much more electronics to reach the same goal like in the first option. Of course in the first option i have to use totaly different approach.
Your requirement of 120 volts at around 5A is about 600 watts. Unless your lamp inverter is rated to drive 750 watts of lighting or more, you are not going to succeed. You first post mentioned that this was a fluorescent light inverter. These don't normally produce anything like that much power.
If it is capable of producing that much output power and you do not care what the output frequency of the 120 volts is, then all you need is a transformer, designed for the frequency of the inverter, to change the inverter output voltage to the required output voltage.
If it is capable of producing that much output power and your output frequency is important and different to the frequency of the inverter, then you will need to both change the frequency and voltage. One way is to change the voltage (using a transformer at the inverter frequency), then convert to dc, then generate an ac output of the appropriate frequency. There are alternate approaches.
Both of these approaches are technically demanding. Designing a power transformer that will work at the few tens of KHz that an inverter would typically generate is far from trivial. Designing a 600W ac generator is far from trivial.