Hello everyone! I have to ask for help with the solution of the issue. An acquaintance brought the amplifier for repair, one capacitor constantly breaks down. The capacitor starts to get very hot when we load the amplifier over 20-30% of the power. Amplifier STETSOM 10k2.
An externally hosted image should be here but it was not working when we last tested it.
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Have you looked at the waveform across that capacitor and the corresponding capacitor for the other half of the amp when loaded?
What are you trying to show with the scope waveform?
What are you trying to show with the scope waveform?
On my oscillogram on the capacitor, there is such a picture. The second capacitor is the same, but much smaller. I'm probably confusing you. Can you tell me what you need to understand, I will definitely try to do it.
With best wishes!
With best wishes!
Correct me where I'm wrong.
The cap that's failing is connected between the high-side drain and the low-side source. This is essentially across the rail voltage, after the high-side shunt resistors.
The shunt resistors that you have the scope across connect between the positive rail and the high-side drain.
Assuming that the above is true, what does the waveform across the shunt resistors showing?
The cap that's failing is connected between the high-side drain and the low-side source. This is essentially across the rail voltage, after the high-side shunt resistors.
The shunt resistors that you have the scope across connect between the positive rail and the high-side drain.
Assuming that the above is true, what does the waveform across the shunt resistors showing?
Hello dear Perry. I did solve this problem. Its was in the quality of capacitors. Supplied Wima capacitors
The first time he was brought with a problem - the output stage and the power supply burned out. I quickly rebuilt the voltage converter and amplifier. One of the capacitors for which I gave the description above was out of order. I replaced 2 with new ones. I sent the amplifier to the client, a week later the client writes the amplifier smoked. An autopsy showed that the amplifier was working, but the capacitor was smoking.
How close to the cap's rated voltage is the rail voltage?
Do you see any excessive noise on the positive rail that could cause the cap to fail?
Do you see any excessive noise on the positive rail that could cause the cap to fail?
The bus voltage is 200V, the voltage of the capacitors that were native if I am not mistaken is 250V (blue). I put the brown ones on the photo.
then put WIMA 400v
then put WIMA 400v