Rigol DP832 Repair Part3

In this video I take another look at my faulty RIGOL DP832 linear power supply which has developed a habit of randomly resetting itself. It has done this since new but recently it has got much worse and sometimes resets every few minutes making it a useless piece of equipment. Lets try to permanently fix it.

[tries]

Great job.
Your findings (with very good explanation) confirm what I figured out more than a year ago. Insufficient decoupling caps on the 4.2V rail. After having added some decoupling caps, my DP832 is now running 24x7 for >1 year without any issue.
There is a thread on the eevblog forum that includes my findings and some pictures.

And I do support your critics on Rigol about poor design. The datasheet of the MCU clearly indicates the *requirement* of a handfull of decoupling caps, which was simply ignored by Rigol.

[lmamakos]

Amazing detective work, well done! I find videos like this wonderful to watch, and see the problem-solving and diagnosing process in action.

[bartomiejmiara]

Great job - Rigol should hire you to correct their fatal design flaws.

[randycarter]

The analog boards have their own control processors. They don't immediately stop when the main control CPU quits. There is a command stream timeout to account for minor CPU distractions. During restart the CPU will issue a channel reset command to the channels.

[frogandspanner]

I don't know if I've caught this in mid-upload - but only 480x360 seems available.

[john_in_phoenix]

Thanks again Jerry. I love your videos, very informative to hear your thought process. Hard to believe that swapped positive and negative was "inspected". While not a "top of the line" brand, Rigol does have a good reputation, but I am not seeing it in this supply. BTW, how is your Riden RD6012 holding up? For the price, I am quite pleased with mine. I purchased both the Kunkin load, and an East Tester ET5410, and like the user interface of the ET5410 quite a bit better.