Smouser
Member
- Messages
- 967
- Location
- Amesbury, Wiltshire, UK
I purchased a Chinese LCD DRO from eBay in early 2023 for my milling machine and it worked great until now.
A few days ago when I turned the mill on, the DRO was dead. No beep, nothing on the screen.
It is a ToAuto DRO-3VA DRO.
To open it up, I only needed to remove 4 Philips screws.
The DRO side PCB.
The power supply PCB
I could not see anything obviously wrong.
The first test was to see if 220V reaches the power supply PCB once it has gone through the switch.
All good, 220V was reaching the power supply PCB.
The next step was to check the DC output of the power supply, it should be 5V.
This is where I was getting weird readings, the readings cycled through 0V, 2V, 5V, 0V, 3V, 6V, 0V, 4V etc.
I was hoping that the actual DRO part was still working and connected an external power supply (5V, 0.5A) to the DRO PCB.
Success!
Now I need to try and find a new 5V power supply PCB.
Unless somebody can tell me what component needs replacing on the power supply which will cause the output voltage to cycle.
*edit* 5V Chinese power supplies are so cheap, that it is probably not even worth trying to repair the existing one.
Amazon prime example
However, it might be worth buying a power supply from a 'reputable' company to avoid the same issue in the future.
A few days ago when I turned the mill on, the DRO was dead. No beep, nothing on the screen.
It is a ToAuto DRO-3VA DRO.
To open it up, I only needed to remove 4 Philips screws.
The DRO side PCB.
The power supply PCB
I could not see anything obviously wrong.
The first test was to see if 220V reaches the power supply PCB once it has gone through the switch.
All good, 220V was reaching the power supply PCB.
The next step was to check the DC output of the power supply, it should be 5V.
This is where I was getting weird readings, the readings cycled through 0V, 2V, 5V, 0V, 3V, 6V, 0V, 4V etc.
I was hoping that the actual DRO part was still working and connected an external power supply (5V, 0.5A) to the DRO PCB.
Success!
Now I need to try and find a new 5V power supply PCB.
Unless somebody can tell me what component needs replacing on the power supply which will cause the output voltage to cycle.
*edit* 5V Chinese power supplies are so cheap, that it is probably not even worth trying to repair the existing one.
Amazon prime example
However, it might be worth buying a power supply from a 'reputable' company to avoid the same issue in the future.