SK80H / GXJA0673 buck-boost DC-DC adjustable power supply

[Razvan_N]

Let's discuss this inexpensive power supply module from Ali.

XY-SK80H / GXJA0673 / D13-13-B-06 is an adjustable buck-boost DC-DC converter that goes from 0.6 to 36.5 V and 5.2 amps, from an input ranging between 6 and 36 volts.
I'm using it as a field power supply, mounted on a 18 V power tool battery. It works great, it is very practical but it lacks a proper manual. There are some floating around but for an older version of it.

Besides the constant voltage / current adjustments, one can set a low input voltage protection (LVP, preventing overdischarge of the battery), overvoltage protection (OVP, handy in case you want to prevent accidentally adjusting too high a voltage), overcurrent protection (OCP), over-power protection (OPP, threshold is in Watts), over-capacity (OAH, Ah, for battery charging), over-energy protection (OPH, Wh), timer (OHP) and startup settings (whether or not to start in the on or off state, and whether to start in constant voltage or constant current state).

However, on one unit I get an error saying OEP (?!) as soon as I connect even the tiniest load to it (e.g. a voltmeter). I suspected having to do with some over-energy protection that is set much too low, but this one is actually called OPH and it is disabled. I could not find anything about this OEP condition or a method to reset the thing to factory settings.

Does anyone have more experience with this module?

[thm_w]

What voltage are you supplying?

Current precision: ±0.4%+ 3 bytes
Capacity: 0-999999AH
Energy: 0-999999WH
Time: 0-1000Hours

Hardware protection: output short circuit protection, output anti backflow protection, can directly charge the rechargeable battery, without additional anti backflow diode.

Software protection: over voltage protection (OVP), over current protection (OCP), over power protection (OPP), over temperature protection (OTP), input low voltage protection (LVP), power chip self protection (OEP).

) power chip itself also has various protection, if the chip itself is protected, OEP will be displayed.

Maybe some FET is blown?
So you can output a voltage all the way up to 36V and it will say 0A on the display?

[Razvan_N]

Yes, I can adjust voltage up to 36.5 V. Where did you find the instructions quoted?

[thm_w]

Google OEP buck boost and you'll find other similar devices or rebrands.

Try connecting a resistor as a load, then turning it on?

[Razvan_N]

The Aliexpress seller agreed to send me a replacement on a future order (which I already made).
Still, I'm interested to fix this if possible, so please write if someone has experience in troubleshooting this model.