Power supply uses IRFZ44 with 47 ohm gate resistors .
Should I replace them with IRFZ44N or would the 3205’s be better ?
Should I replace them with IRFZ44N or would the 3205’s be better ?
Replaced the power supply fets gate resistors and drivers .
All of the outputs test fine .
As soon as I apply remote voltage amp draws excessive current
Any ideas ?
All of the outputs test fine .
As soon as I apply remote voltage amp draws excessive current
Any ideas ?
Here is what I bet for drive signals for the power supply fets .
Scope set to 5us 5 volts/div
0.1uf cap from gate to source
As soon as I apply remote amp draws excessive current all of the outputs test fine
Scope set to 5us 5 volts/div
0.1uf cap from gate to source
As soon as I apply remote amp draws excessive current all of the outputs test fine
Attachments
All of the outputs and ceramic boards are removed from the amp .
The amp will draw excessive current with the rectifiers in .
If I remove the rectifiers the amp powers up normally .
Any ideas ?
The amp will draw excessive current with the rectifiers in .
If I remove the rectifiers the amp powers up normally .
Any ideas ?
Must be something in the output section or the rectifiers are dead I think.
Have you checked the rectifiers if they are ok?
If they are ok, is anything in the output section getting too hot?
Have you checked the output fets/transistors?
Do you have a photo from the internals?
Have you checked the rectifiers if they are ok?
If they are ok, is anything in the output section getting too hot?
Have you checked the output fets/transistors?
Do you have a photo from the internals?
I replaced the power supply fets ,gate resistors , and drivers
I also replaced the rectifiers .
I’ve removed all of the outputs and ceramic driver cards along with the regulators .
If I leave the rectifiers out of the amp the power supply will power up and idle fine .
If I put the rectifiers in the amp it will draw excessive current.
I’ve checked for solder bridges can’t find any .
Any ideas ?
I also replaced the rectifiers .
I’ve removed all of the outputs and ceramic driver cards along with the regulators .
If I leave the rectifiers out of the amp the power supply will power up and idle fine .
If I put the rectifiers in the amp it will draw excessive current.
I’ve checked for solder bridges can’t find any .
Any ideas ?
Are the black diodes in parallel with the regulator transistors shorted?
Are the 1 ohm resistors in series with the regulators burning?
Are the 1 ohm resistors in series with the regulators burning?
What do you consider excessive current?
Is it a steady draw or just a pulse?
Which transistors heat up if the amp is powered up for a few seconds?
Does the excessive current draw change if you install either regulator (but not both at the same time)?
Is it a steady draw or just a pulse?
Which transistors heat up if the amp is powered up for a few seconds?
Does the excessive current draw change if you install either regulator (but not both at the same time)?
The amp draws 40 amps of current .
The power supply fets get very hot instantly .
It draws 40 amps of current continuously .
If I install 1 rectifier but not the other it still
Draws excessive current as soon as I supply remote voltage .
Only way the amp will not draw excessive current is if I remove the rectifiers
The power supply fets get very hot instantly .
It draws 40 amps of current continuously .
If I install 1 rectifier but not the other it still
Draws excessive current as soon as I supply remote voltage .
Only way the amp will not draw excessive current is if I remove the rectifiers
It's generally where the terminal windings meet the rest of the windings. It's best to find it before removing the inductor.