Hi bros, I had repaired a Lightning Labs 5000.1F Generic mono amp 5000watt with a power supply issue. It was working fine but when you crank up the volume of my receiver say pass 11 o'clock the mono amp goes on protect mode. I have to turn OFF and ON again the amp to get it back to work. The amps gain set to 12 o'clock, LPF 50Hz and 9 @ the processor. But with other mono amp 3000 watt replaced it is working fine even at high volumes and same amp setting. What seems to make the amp go to protect mode at higher volume? Car Power supply and wirings are seem to be fine. Thanks you very much.
Do you have any test tones/tone generator so that you can play a constant signal and slowly increase the level to see if the amp goes into protection at 13.4v (or any consistent voltage)?
Voltage dropping is normal but most amps don't go into protect from low voltage until about 11v.
That said, the voltage can dip so quickly (especially with music) that a multimeter can't respond quickly enough to read the drop in voltage that's causing an amp to go into protect.
Post a good quality photo of the component side of the entire main board and the component side of any driver boards.
Voltage dropping is normal but most amps don't go into protect from low voltage until about 11v.
That said, the voltage can dip so quickly (especially with music) that a multimeter can't respond quickly enough to read the drop in voltage that's causing an amp to go into protect.
Post a good quality photo of the component side of the entire main board and the component side of any driver boards.
hi bro, attached is the photo of the component side , it doesn"t have driver board , IC drivers are all embedded on the board. I tried checking signals at gate drive of hi and lo at each bank , I don't get that usual square wave drive but it shows like a distorted saw wave but when I put 50hz sine wave signal in the input and check the output(speaker terminal) I get that clean sinewave which should be. Is the distorted saw wave on the gate drive FET's normal? By the way i replaced 3 FETs (with different manufacturer) only in the bank that had a shorted FEt's. should I replace the entire FET's? I am using only a DIY DSO150 mini Oscilloscope, is this good enough in signal tracing at high frequency?
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Oh i see, since i am just a novice. I had tried this oscilloscope and a DIY Function generator XR2206, the generator seems working well. You mean i am getting wrong drive signal because of the oscilloscope not displaying well? being said, is the amp working well, what seems to be the problem for it protects turning the volume up. Shall i replace all the output FETs of the same manufacturer? By the way attached are the gate drive signals. as i was telling of a saw wave, Lo and Hi respectively. with and without signal the same waveform, but getting a nice sine wave at the output terminals @50 hz input.
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The scope isn't going to be reliable for output stage waveforms on the FETs. About all it can do at the high frequencies of the output stage is to determine if a waveform is present.
Post a photo of the area shown below that's sharp enough to read the markings on the components.
Post a photo of the area shown below that's sharp enough to read the markings on the components.
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hi What is your rail voltage when the amp is playing. Also have you checked to see what is your output AC voltage. I stand to be correct but around +50V AC you should get around 3k if my rough calculations are correct. also can you please post a close up picture of output drive section of the amp. Cannot see the components of the one you posted.
Yep you do have a problem in the over current stage of the amp. can you post pics of the amp but close ups. This way we can to figure out which amp their have cloned or someone on this forum might know this amp.
From what i could see from your previous pics this looks like a copy of a Brazilian amp but which amp it was hard to say .
also check your PM
From what i could see from your previous pics this looks like a copy of a Brazilian amp but which amp it was hard to say .
also check your PM