Hello everyone.
I have a Rockford T10001bd PC-5445-B amplifier.
The amp has good gate drive on power supply.
The amp is making rail voltage.
The amp is making regulated voltage.
There are no shorted outputs.
The protect light is lit brightly, the output stage is not getting any rail voltage to the rail switchers or outputs.
There is 2,250vdc on the output terminals.
Q202 and Q201 are getting very hot, but nothing else is getting hot, neither test bad in circuit. They are PZTA56 and PZTA06.
So far I have not been able to locate a fault, any help would be appreciated.
I have a Rockford T10001bd PC-5445-B amplifier.
The amp has good gate drive on power supply.
The amp is making rail voltage.
The amp is making regulated voltage.
There are no shorted outputs.
The protect light is lit brightly, the output stage is not getting any rail voltage to the rail switchers or outputs.
There is 2,250vdc on the output terminals.
Q202 and Q201 are getting very hot, but nothing else is getting hot, neither test bad in circuit. They are PZTA56 and PZTA06.
So far I have not been able to locate a fault, any help would be appreciated.
Yellow protect not red thermal.
I'll check R49 and R50.
I know they run warm but they get warm quickly without the output stage being turned on.
I'll check R49 and R50.
I know they run warm but they get warm quickly without the output stage being turned on.
It may be in over-current protection. If you want to defeat it, slide D202 off of its pads. Be careful.
I lifted D202 and the amp powered up and the rail switchers and ouputs had rail voltage. It had proper current draw for idle, then started pulsing like an initial rail cap charge on start up.
Does this mean that there is an actual over-current condition?
Are the FETs clamped or not (to see which are heating)?
Are the FETs clamped or not (to see which are heating)?
The board is out of the heat sink, I could put a current limiter inline and monitor the output FET's to see if any heat up. Although they all test good.
I am usnsure what could cause an over current condition at this point.
I will use the current limiter and see if any FET;s are heating up, as I dont want to damage the power supply.
I am usnsure what could cause an over current condition at this point.
I will use the current limiter and see if any FET;s are heating up, as I dont want to damage the power supply.
You could clamp all of the components except the outputs.
Remember that you can insert a limiter for the secondary alone by inserting it in series with the output of one of the rectifiers.
You can also troubleshoot without any secondary rail voltage.
Many options, at this point.
The outputs may be OK but have a leaky driver or something similar. Knowing what's heating up could narrow down the area to look.
Remember that you can insert a limiter for the secondary alone by inserting it in series with the output of one of the rectifiers.
You can also troubleshoot without any secondary rail voltage.
Many options, at this point.
The outputs may be OK but have a leaky driver or something similar. Knowing what's heating up could narrow down the area to look.
Well didn't take long to figure it out lol
With the current limiter in place Q208 and Q209 are heating up fairly quickly.
These are both audio FET's and not rail switchers.
With the current limiter in place Q208 and Q209 are heating up fairly quickly.
These are both audio FET's and not rail switchers.
Well the drivers test good, but I hear a high pitched frequency noise on the board. If I wiggle T200 it makes the sound worse. I'm wondering if the U202 driver or the T200 transformer may be defective.
Could this cause an over current condition?
I'm always open for suggestions.
Could this cause an over current condition?
I'm always open for suggestions.
Virtually any drive issue could cause over-current.
What scope are you using (mains powered or handheld, battery powered)?
Can you relatively easily lift/disconnect the main rectifiers?
What scope are you using (mains powered or handheld, battery powered)?
Can you relatively easily lift/disconnect the main rectifiers?
I could desolder the legs of the rectifiers and lift them and their MESHA board off the main board.
My 465 is giving me fits and won't trigger.
I have a Vellamen HPS40 hand held battery powered scope that works OK.
My 465 is giving me fits and won't trigger.
I have a Vellamen HPS40 hand held battery powered scope that works OK.
Disconnect the rectifiers. The center terminal is all you need to disconnect.
Trigger level? Trigger source? Decrease vertical amplifier to produce larger trace?
My 465B went down and I'm devastated. No trace, not even with the trace finder. All voltages that I checked were clean and present.
Is the diagram I sent you closer than the one you posted, or the same?
Trigger level? Trigger source? Decrease vertical amplifier to produce larger trace?
My 465B went down and I'm devastated. No trace, not even with the trace finder. All voltages that I checked were clean and present.
Is the diagram I sent you closer than the one you posted, or the same?
That's a newer version of amp that uses the LM5110 drivers that you sent me.
This amp uses the UC3706DW
The rectifiers are disconnected.
This amp uses the UC3706DW
The rectifiers are disconnected.
Bridge pins 1 and 2 of U200. That should give you a 50% duty cycle on the drive circuit.
Check all drive circuits with the scope connected directly across the gate and source terminals of the output FETs. Do all look like good clean signals?
Check all drive circuits with the scope connected directly across the gate and source terminals of the output FETs. Do all look like good clean signals?
I was probing the pins of the 3706 before doing the test you asked and found pin 2 of the 3706 which goes to pin 7 of U203 had no voltage.
I checked the other driver and it had 5.85vdc.
I checked R232 and it tested good in and out of circuit but no voltage was going across it.
I replaced it and now have the voltage to pin 2 of U202.
Question is, could this cause a drive issue and do you think its possible this was the culprit?
I checked the other driver and it had 5.85vdc.
I checked R232 and it tested good in and out of circuit but no voltage was going across it.
I replaced it and now have the voltage to pin 2 of U202.
Question is, could this cause a drive issue and do you think its possible this was the culprit?