EEVblog #1023 - Rigol DL3021 Electronic Load Teardown

[Wolfgang]

One datapoint: I just blew up my DL3021 after using it with a 155V input at 200W. Yes, slightly over-limit, but I didn't expect it to fail short on the pass FET almost immediately. It sinks about 7A at 1.4V permanently now, very disappointing.

The FETs they use are normal switching types, and some in parallel. If you need to replace them anyway do this by IXYS Linear types.

[dougg]

Sad to hear the DL3021 can't handle even slight over-voltage.

On the bright side I have a Panasonic 7S4P Li-Ion battery rated at 25.2 Volts and 10.8 Amps. So I set up my DL3021 to dissipate 200 Watts in CC mode. Then I wound up the wick on the current, expecting a pop-up to say the power rating was exceeded. No warning, so I stopped at 10.8 Amps. The display was showing 25.8 Volts and 280 Watts. The fan sounded like it was preparing for take-off. The ambient temperature is around 19 C which probably helped.

BTW That battery is used in a lightweight electric trike. And at less than 300 Wh that battery can be carried in a plane cabin (while the rest of the trike goes with the checked-in luggage).

[electr_peter]

They could definitely sell/include a small adapter PCB though, to convert the huge terminals to standard banana jacks. Would be easy for someone to design one.

I was fiddling around with connecting test leads to this load which was pretty annoying. I found some adapters for other binding post distances but none for 39 mm distance here. So finally I ended up with building my own adapters: https://github.com/sirhcel/dl3000-adapters You could order the PCBs directly from OSH Park for convenience.

You can use 4mm socket fork adapter as well https://www.ebay.com/sch/i.html?&_nkw=4+mm+socket+fork+adapter

[KlausF]

Hi guys!
Any idea how to disable or reset the "System boot times" counter (Utility menu -> System Information) of Rigol DL3021(A) ?

[electr_peter]

Dave mentioned (EEVblog #1023 - Rigol DL3021 Electronic Load Teardown, 43:58) that one model would make more sense in terms of price. Well, forum member confirmed that all models of DL3000 range share the same HW and can be simply hacked to top version (dl3021-to-dl3031-conversion-discussion)