I've recently installed a new Charge Controller MPPT 75/10 to my fairly basic van system (see wiring diagram), and after a few teething troubles, succeeded in getting it all up and running (see screenshot from VictronConnect app – it was dull day). A few hours later, however, the Controller was cycling every couple of seconds between Bulk and Off states. A little exploration on this community pointed to a blown fuse in the Controller, and that seemed to be the problem.
I've now replaced the fuse four or five times, but as soon as the breaker between the Controller and the battery is closed, it blows again. I've tried disconnecting the PV panels at the breaker switch on the right, and opening the breaker between the leisure battery and the DC to DC charger. I've checked all my polarities are correct and looked for potential shorts, but everything seems in order. The fuse still blows every time I close the breaker. Everything connected to the fuse box is working.
There's a page on the Victron support site that suggests the unit may be faulty, but before I send it back, I wondered whether anyone here might shed some light on this?
Many thanks