Where to source broken non chinese offgrid MPPT controllers and inverters?

[plopa]

Hi all,

i want to learn more about offgrid MPPT controllers and inverters and eventually want to be able to build my own design
based on existing proven and working designs from non chinese brands like for example:

Victron, Studer, Midnite, Outback, Schneider

I found it very difficult to find broken units on ebay as they are probably often thrown away even when they where expensive to buy and the unit seem to fail more often like MPPT controllers.

[mikeselectricstuff]

Maybe contact some local solar installers

[Roehrenonkel]

Maybe contact some local solar installers

...possibly with a crate of beer (or other local beverage), so they remember you. ;-))

Good luck

[f4eru]

You might get an "inverted survivorship" bias, i.e. analyzing only the models that like to fail
But still a good idea.
Please share the board photos

[plopa]

i already have learned a lot by following this tutorial:

https://www.instructables.com/DIY-1kW-MPPT-Solar-Charge-Controller/

i recommend anyone interrested in the topic to do the same.

but i guess the commercial MPPT controllers have a lot more additional safety measures then this DIY MPPT and they still seem to fail quite often.

from what do they fail? overvoltage? voltage spikes? just too small mosfets used at 100% which gets too hot?

this things i want to research and avoid in my own design.

[Psi]

i already have learned a lot by following this tutorial:

https://www.instructables.com/DIY-1kW-MPPT-Solar-Charge-Controller/

Interesting,