Victron dc to dc charger detected that there was a fault in my electrical system so I use the Bosch thermal camera to identify a fuse that was getting too hot, after replacing this fuse, the Victron DC to DC. Charger is now working perfectly. 
Bosch Professional 12V System Thermal Camera GTC 400 C (2x 12V Battery + charger, Pouch, w/app function, Temperature Range: -10°C to +400°C, Resolution: 160 x 120px) - Amazon Exclusive Set
Philip Holloway is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for my site to earn advertising fees by advertising and linking to Amazon products. I may earn a small commission if you purchase via my link. But it doesn't cost you any more, it just helps me to grow my channel
Here is my link to Amazon for the Bosch Thermal Camera
amzn.to/3j2PGJT