Dynacord 1600-3 protect led

[wondrous]

HI
I HAVE DYNACORD 1600-V3
it stop with protect red led
it come to me from another repair workshop
i check power side all seem ok
controller feed with 5 volt , also power good signal is send to main processor board
and i have another board and i do a compare with it all seem to be ok at power side
is there any other reason for red protect led i had to check ?
also is there are any schematics for it , i have one but it hand drown ?
thanks in advance

 

[FvM]

User manual tells DC at speaker output is a possible cause of triggering protection circuit. But I don't understand how protection works here, there are apparently no speaker relays. Does protection shut down high power SMPS til next power cycle, only keeping LV supply?

--- Updated Mar 11, 2025 ---

What's the state with active protection LED, +/- 120 V rails powered or off, voltage at speaker outputs?

 

[wondrous]

User manual tells DC at speaker output is a possible cause of triggering protection circuit. But I don't understand how protection works here, there are apparently no speaker relays. Does protection shut down high power SMPS til next power cycle, only keeping LV supply?

--- Updated Mar 11, 2025 ---

What's the state with active protection LED, +/- 120 V rails powered or off, voltage at speaker outputs?

Thanks FvM
The whole board is live not just Low voltage section.
120v Rail exists but it's 88 volts to 95 volts
Last check withe solar power inverter and sun tend to set
After outlet main 220v get pack i would check it again
At speakers out there is no DC .
And the device accepts signal and level indicator operating will also main screen reacting will . All things tend to be good except it tourn led red protect and stay that way until you shut it down

 

[D.A.(Tony)Stewart]

Does it fail on power up?
Can you disconnect speaker and scope output?

Does it matter if speakers are connected ?
Does disable protection work?
Is it a false error or real fault?

It says it measures RMS Voltage or is it RMS current ?
AC (oscillation) or DC ( you said none)

 

[wondrous]

Does it fail on power up?
Can you disconnect speaker and scope output?
View attachment 197971
Does it matter if speakers are connected ?
Does disable protection work?
Is it a false error or real fault?

It says it measures RMS Voltage or is it RMS current ?
AC (oscillation) or DC ( you said none)

Hi
No it start normally with all led on but protect led stay on.
There is no speakers connected to the amplifier.
Also it doesn't matter if speakers are connected.
Yes disable protection choices work and the rest can be selected as well also not solve the problem.
unfortunately i didn't have oscilloscope to scope oscillation.
The owner of this device told me that before it come to me it work but restart rabidly.
They change SMPS Ic LNK306GN with new one then it stuck in protection state.

--- Updated Mar 12, 2025 ---

I desolder SMPS IC witch generat 16 volt
And feed 16 volt from multiple voltage selected power supply range from 12 TO 24v
It operate well with no effect on removing protection led

 

[D.A.(Tony)Stewart]

when protection is disabled., check output in Vac ,
if 0V AC then you do not have oscillation or over-voltage, so maybe false error,
Check all DC voltages against schematics in service manual

 

[wondrous]

when protection is disabled., check output in Vac ,
if 0V AC then you do not have oscillation or over-voltage, so maybe false error,
Check all DC voltages against schematics in service manual

Thanks yot but sorry the service manual you share is for version 2 but i have version 3
Dynacord powermate1600_3

 

[D.A.(Tony)Stewart]

ok then follow the LED source and get -3 schemas p.96+

+/-120Vdc
+/-16Vdc
etc

--- Updated Mar 12, 2025 ---

 

[wondrous]

ok then follow the LED source and get -3 schemas p.96+

+/-120Vdc
+/-16Vdc
etc
View attachment 197977

--- Updated Mar 12, 2025 ---

View attachment 197979

Good evening
I have this hand drawn schematic
There are atmega48 in SMPS side it linked with other board only with opto and transformer
One of opto send power good signal to other main poard
I check the signal from SMPS side its 0v and compared with another device and it's ok.
Also i left diode of opto side to have different signal at receiver and it stay at protection mode .

--- Updated Mar 13, 2025 ---

ok then follow the LED source and get -3 schemas p.96+

+/-120Vdc
+/-16Vdc
etc
View attachment 197977

--- Updated Mar 12, 2025 ---

View attachment 197979

Thanks you

 

[D.A.(Tony)Stewart]

So "Power Good" is not the same as "Protect" which is not shown on any page.

 

[wondrous]

Yes it's not the same but it may trigger protect
Pack their i repair a device with protection led
The problem is one of output resistor
If i can remember 4.2 ohm high wattage value get open
I replace it with 5 ohm and it remove protection and the device work fine