Please help!
Negative rail voltage falls faster than + rail voltage, is this a sign of bad capacitor? It's very rare I encountered a bad capacitor, please educate me how I will diagnose them except for physical appearance. If any of caps is bad, rail to rail may have not equal drain rate? right?
symptoms of this amp:
1. Blue light comes on and relay ticks, after 1 second red light lights on and protect mode.
2. I have a negative rail voltage in the speaker side before protect mode.
3. I measured -rail voltage to all gate terminals in the high side and low side output fets.
Do I have problem also with the driver board? this is for 3000 Watts amp common to american amps, please see attached image.
Happy New Year to All! more powers!!!
Negative rail voltage falls faster than + rail voltage, is this a sign of bad capacitor? It's very rare I encountered a bad capacitor, please educate me how I will diagnose them except for physical appearance. If any of caps is bad, rail to rail may have not equal drain rate? right?
symptoms of this amp:
1. Blue light comes on and relay ticks, after 1 second red light lights on and protect mode.
2. I have a negative rail voltage in the speaker side before protect mode.
3. I measured -rail voltage to all gate terminals in the high side and low side output fets.
Do I have problem also with the driver board? this is for 3000 Watts amp common to american amps, please see attached image.
Happy New Year to All! more powers!!!
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If any of the outputs were bad then the driver IC's on the driverboard have failed as well...
Unsolder the driverboard and power the amp up to see if it still protects..
Most likely there is a defective component or componets on the driverboard.. The only thing ive seen that causes thoose amps to protect is either you have shorted or leaking outputs or there is a problem with the driverboard
Unsolder the driverboard and power the amp up to see if it still protects..
Most likely there is a defective component or componets on the driverboard.. The only thing ive seen that causes thoose amps to protect is either you have shorted or leaking outputs or there is a problem with the driverboard
Anyhow..I would gladly get rid of those ´CrapXon´ -caps. CapXon´s are the most badcap ever in my opinion.
Do the power FETs warm up?
What does it draw current from your 12V supply?
Does every each of amp FETs measure the same resistance from outer legs? What is that resistance?
Have you pulled out those amplifier FETs? If so, try to measure ohms straight from board..
So if you choose to change atleast those secondary capasitors, you can pull them out and start up the amp..then you´ll find out if they were the problem. And as said, not a bad idea to replace them with Panasonic or Rubycon anyway
Do the power FETs warm up?
What does it draw current from your 12V supply?
Does every each of amp FETs measure the same resistance from outer legs? What is that resistance?
Have you pulled out those amplifier FETs? If so, try to measure ohms straight from board..
So if you choose to change atleast those secondary capasitors, you can pull them out and start up the amp..then you´ll find out if they were the problem. And as said, not a bad idea to replace them with Panasonic or Rubycon anyway
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There is more of a load on the negative rail. All of the components on the audio driver board are powered by regulators that feed off of the negative rail.
U3 or U4 could be defective. To determine if they're functioning normally, you'd have to measure the DC voltage on all pins of both ICs before the amp goes into protect and shuts down. You could prevent it from going into protect by defeating the DC offset protection but that could be risky.
U3 or U4 could be defective. To determine if they're functioning normally, you'd have to measure the DC voltage on all pins of both ICs before the amp goes into protect and shuts down. You could prevent it from going into protect by defeating the DC offset protection but that could be risky.
Anyhow..I would gladly get rid of those ´CrapXon´ -caps. CapXon´s are the most badcap ever in my opinion.
Do the power FETs warm up?
What does it draw current from your 12V supply?
Does every each of amp FETs measure the same resistance from outer legs? What is that resistance?
Have you pulled out those amplifier FETs? If so, try to measure ohms straight from board..
So if you choose to change atleast those secondary capasitors, you can pull them out and start up the amp..then you´ll find out if they were the problem. And as said, not a bad idea to replace them with Panasonic or Rubycon anyway
output fets in good shape...
Thank you very much Perry and et al!
May I know what are the part numbers of U1, U2, U3 and U4? This is my first time to repair driver board
And also please tell me what are the components responsible for triangular waveform generator? If favor, do you have schematics of this?
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