Hello guys, need your help
I've expanded my old system
the old voltronic axpert king has these firmware
U1 71.41
U2 01.12
U3 00.21
U4 00.00
and the new one
U1 71.93
U2 02.60
U3 00.24
U4 00.00
Which firmware versions can I upgrade my inverters to connect them in parallel? and from where can I get it?
thanks a lot