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Hello.
I have an issue with a 32v psu for a led light system.
Basically 2 screws came loose and touched the board. Failed mid show. No blown fuse or any burnt component.
So I changed the uc3842 and it came up and provided 32v found a 470r supply resistor to the opto coupler burning up. Changed the opto and WL431 ic all working.
Connected back up psu is pulsing. With the other two boards connected. I don't have a bench psu. So put together a test one. Led system working ok
So it's most definitely psu at fault
It seems to be not able to supply enough current to the 2 boards.
Changed / swapped out
secondary diode
Secondary caps
Primary caps
Changed the uc3842 2nd time
Checked all components on board can find nothing wrong. All in spec.
There is a preset pot on secondary in the opto circuit
I have loaded up the output 32v with a some resistors and if I go down to about 39 ohms 5watt. The psu will start pulsing. ( 6v-10v)Anything above that the psu keeps on pushing out 32v. Can't find a schematic.
If anyone can shed some light I would be grateful
I have an issue with a 32v psu for a led light system.
Basically 2 screws came loose and touched the board. Failed mid show. No blown fuse or any burnt component.
So I changed the uc3842 and it came up and provided 32v found a 470r supply resistor to the opto coupler burning up. Changed the opto and WL431 ic all working.
Connected back up psu is pulsing. With the other two boards connected. I don't have a bench psu. So put together a test one. Led system working ok
So it's most definitely psu at fault
It seems to be not able to supply enough current to the 2 boards.
Changed / swapped out
secondary diode
Secondary caps
Primary caps
Changed the uc3842 2nd time
Checked all components on board can find nothing wrong. All in spec.
There is a preset pot on secondary in the opto circuit
I have loaded up the output 32v with a some resistors and if I go down to about 39 ohms 5watt. The psu will start pulsing. ( 6v-10v)Anything above that the psu keeps on pushing out 32v. Can't find a schematic.
If anyone can shed some light I would be grateful