The 25A fuse in my Victron MPPT charge controller was burnt—it was not blown. The fuse connection at the circuit board where the fuse plugs in was also burnt. A further point is that only one leg (blade) of the fuse was burnt; It was the outermost leg closest to the charge controllers case. It is my understanding that this fuse is used for the “Load Output” feature (I have an older model). I do not use the load output feature and have disabled it through the app. A lot of current went through that leg of the fuse.
I have recently been having problems fully charging my batteries. There has been failures with the charge controller where the PV voltage was 77.9V 0.0A, and battery was 13.00V 0.20A. I had to disconnect the charge controller to reset it. After reconnecting I got a normal PV reading of 63.74V and 2.5A. I checked for error codes in “History,” but none were set. Also, during charging the controller keeps my batteries in bulk charge much longer than usual (my system has been working since December 2020) and absorption times higher than I’ve ever seen. The amount of sun/clouds is the same on average as it has been the past 2 years.
Any thoughts as to why/what burnt the fuse; What caused such high current to flow through one leg of the fuse, and the recent behavior of the charge controller showing high PV voltage with zero amps?
Charge Controller Firmware: v1.59
Charge Controller Interface - Firmware: v2.41; Bootloader: v1.16
