Orion 24/12 -25 dc to dc converter as a backup to charge my 12 volt battery from my 24volt battery bank when smaller 12 volt solar supply can’t keep up with charging requirement. I have an older 24/12-20 model I use to charge my generator start AGM battery and it has worked without a problem.
Both the 24 v battery bank and the 12 volt battery are lithium. Connected the both systems as per instruction. Fused the system given the output and input as indicated on the unit. Energised the system and turned on the remote switch I installed. Output 12 volt fuse immediately blew. De energised system and checked all connections and found no problem. Installed BMV on 12 volt battery and safely increased fuse and wiring size to accommodate much more current than the rated 35 amps that can be supplied. Re energised the system and noted on the BMV on 12 volt battery indicated over 45 amps being put out by the converter. I allowed the charge to continue for around 3 minutes until the unit heated to a point where the smell of paint over heating on the unit.
Removed unit and had the unit replaced under warranty. Service agent/seller could not understand how the unit could output so much current above specification.
After the muck around posting the faulty unit back I finally received the new replacement. Same process of installation making extra sure of a strong negative connection I fired the systems up again with the same result again but this time the current hit 50 amps 12 volt with over 25 amp draw on the 24 volt side! Informed the victron service agent again. Weeks went by and all I got was crickets! Contacted service agent again, they have no idea. I thought it may have been a bad batch so in an effort to try and get on the road I purchased another one. Same results!!!
I would say they are not fit for purpose when it comes to lithium batteries. One would think the unit would have some form of protection built in to prevent over current output and possibly avoid a severe overheating/ fire situation?
If anyone has some clue on this I would love to be enlightened
Cheers
Brad
