Author Topic: Rigol DP832 OVP overshooting with huge delay  (Read 85 times)

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Offline Professzore

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Rigol DP832 OVP overshooting with huge delay
« on: Today at 03:10:54 AM »
I've been into "Rigol DS832 experience" since a few days only. The most important of the list of aspects was a trusty overvoltage and overcurrent protection with a fine tuning possibility. Theoretically, DP832 knows it well.
Here I come with my very recent experience with it. Basic setup was a Rigol DS832, a Rigol MSO1074Z and a SiLabs EFM32 Pearl Gecko kit externally powered through the "button cell jumper" with 3.0 V (from this source, only the MCU works, no debugger and other features are available, overall consumption is around 5 mA or less in normal mode). Because I couldn't find any source for a trustable schematics for this evaluation board, I was trying to set-up an overvoltage protection. To test my equipment, I disconnected the Gecko and used a 1k ohm resistor to maintain an approximate 3 mA load at 3V. Only for testing, I set up 3.1 V OVP, 10 mA OCP, and turned the drive voltage to 30 V (the max) with 5 mA current. The first attachment shows the result.
The second is almost the same setting with 3A current set without OCP.
It is clearly visible that Rigol seriously overshoots the OVP setting for an unacceptable long period (500 ms). In the worst case, +27V, which is -- of course -- a killer to a board like this.
My questions:
1. Is there any software solution to "hack" this problem (in a "perfect world" if set voltage is over the limit of OVP, the output can not be turned on in any way)?
2. Is there any hint to avoid any accident regarding the above-mentioned problem?

Thanks a lot for your help,
(BTW, it's a waaaaaay better programmable PSU than my previous Axoiomet.)
Yours sincerely,

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