I am working on a project to make a cold plasma for my Physics class. A cold plasma can be created by running a high voltage, high oscillation current through a wire. I found a proceedure online http://jnaudin.free.fr/html/s_gdp1.htm. I completed the circuit and hooked it up to a commercial 24 volt 3 amp power supply. I turned it on and it produced a plasma for about 20 seconds, but then it stopped working and the power supply started making a sound (My instructor said it sounded like it was overexerting). I turned it off, and I noticed that the IRFZ 34 Mosfet chip was extremely hot. Since then, I have not been able to get it to work.
Since then, the power supply has been acting kinda funny. Whenever i try to power the circuit, the light on the power supply does not light up, and the power supply makes the noise I mentioned earlier. To Troubleshoot, I measured the amps that the circuit was drawing, and found out that it was over 5. I disconnected the circuit and turned the power supply back on, and the power supply seemed to be working fine (No noise and the light turned on).
Because of this, I figured that the Mosfet chip overheated and created a short circuit(The only resistance through the Mosfet chip section of the circuit is an ignition coil) so I replaced it with a new one.
I reconnected the circuit and turned it on, and it acted the same as with the old chip (Power supply light off, but making groaning noise, and no plasma). My instructor recommended replacing the Diode, which I did today, but that didn't change anything.
So basically I'm not sure why the circuit isn't working. I figure something burned out, but I'm not sure what.
Information that may be useful------------------
When it was working, the circuit produces a high pitch sound, but it no longer does.
The Mosfet chip is only rated for 20 volts, but 24 volts were going across it(thats what the instructions called for)
I don't think the power supply went bad because it seems to be working fine when it is not connected to anything
Other than the mosfet chip, there are resistors, a potentiometer, caps, a voltage regulator, and a 555 chip. I doubt any of those would have burnt out since they all see pretty durable and shouldn't have received any unsafe voltage.
Questions
What most likely went wrong with the circuit? By process of elimination, I figured that the 555 chip must be burnt out, but I think those chips are pretty tough.
I added a heat sink to the Mosfet chip, should that keep the mosfet from burning out again?
I still have the old Mosfet chip. Is there any way to tell if it actually did burn out?
Is the power supply still good. When connected to broken circuit, it makes a groaning noise, and the light does not go on (It is pushing over 5 amps and the voltage is about 14 volts instead of 24). It seems like there is a short circuit in the circuit, but it looks fine when it is not connected to the broken circuit, so I don't think that is the problem
If you have any questions about my circuit, just let me know and I'll post more info
Thanks So Much for taking the time to read this!!
-Alex
Since then, the power supply has been acting kinda funny. Whenever i try to power the circuit, the light on the power supply does not light up, and the power supply makes the noise I mentioned earlier. To Troubleshoot, I measured the amps that the circuit was drawing, and found out that it was over 5. I disconnected the circuit and turned the power supply back on, and the power supply seemed to be working fine (No noise and the light turned on).
Because of this, I figured that the Mosfet chip overheated and created a short circuit(The only resistance through the Mosfet chip section of the circuit is an ignition coil) so I replaced it with a new one.
I reconnected the circuit and turned it on, and it acted the same as with the old chip (Power supply light off, but making groaning noise, and no plasma). My instructor recommended replacing the Diode, which I did today, but that didn't change anything.
So basically I'm not sure why the circuit isn't working. I figure something burned out, but I'm not sure what.
Information that may be useful------------------
When it was working, the circuit produces a high pitch sound, but it no longer does.
The Mosfet chip is only rated for 20 volts, but 24 volts were going across it(thats what the instructions called for)
I don't think the power supply went bad because it seems to be working fine when it is not connected to anything
Other than the mosfet chip, there are resistors, a potentiometer, caps, a voltage regulator, and a 555 chip. I doubt any of those would have burnt out since they all see pretty durable and shouldn't have received any unsafe voltage.
Questions
What most likely went wrong with the circuit? By process of elimination, I figured that the 555 chip must be burnt out, but I think those chips are pretty tough.
I added a heat sink to the Mosfet chip, should that keep the mosfet from burning out again?
I still have the old Mosfet chip. Is there any way to tell if it actually did burn out?
Is the power supply still good. When connected to broken circuit, it makes a groaning noise, and the light does not go on (It is pushing over 5 amps and the voltage is about 14 volts instead of 24). It seems like there is a short circuit in the circuit, but it looks fine when it is not connected to the broken circuit, so I don't think that is the problem
If you have any questions about my circuit, just let me know and I'll post more info
Thanks So Much for taking the time to read this!!
-Alex
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