Hello everyone,
I would like to be able to charge my trolling motor batteries from my 115 hp outboard (alternator) starter battery. My starter battery is a 12 volt lead acid battery and my trolling motor batteries are 2 12 volt lifepo4 batteries 100ah each which are connected in series. Is there a Victron product that would work for this application? My outboard motor puts out 85 amps under normal operating conditions.
That would be an Orion-Tr Smart 12/24, and given your smaller alternator I’d personally go with the 12/24-10, but the 12/24-15 may be alright as well.
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Thank you for advising me on the right product I should be going with. I will be going with the Orion Tr Smart 12/24 10 dc to dc isolated charger as recommended
Should I be using some inline fuses with this set up? If yes what size fuses and how many?
It is all in the manual in the installation section
Yes, all DC circuits must always be equipped with overcurrent protection devices, with zero exception. The installation manual linked above is the place to start, and also have a look at the DC Wiring section of Wiring Unlimited, which goes into greater detail of the necessary calculations and considerations of DC wiring in a system: 4. DC wiring
Thank you for the info and link
Thank you
Don’t choose fuses according the appliances, but fitting to the wire size used.
That is the non-isolated in the picture. The isolated has 4 terminals. You should not be connecting a common ground like that.
I have the 12/12 18amps for my trolling motor. So that is 18 amps out. I measure about 21A into the unit. You are going to be 18A at 24V so I would expect the input current to be twice mine at ~41A.
I have a Honda 130 with a 65A alternator and the charger gives it a workout. I would look at the 10A charger. See if you can get the alternator rpm and current curve. Mine is,
10A at 1500
30A at 2000
48A at 4000
65A at 5000
I purchased the 12/24 orion tr-smart charger 10amps isolated 4 terminal. Will this wiring diagram for the 4 terminal orion charger work for my set up?
You nailed it. Also look at a battery balancer for the 24V. Victron have one. There are other like litime fo Mrpow that work well.
I had a look at the battery balancer and I will be adding that to my setup, It’s a good idea it will prolong the life of my batteries. I am three quarters of the way there for setting up my charging system for my trolling motor batteries. All I need now is to figure out the fuses I require still a little confused with that part.
The fuse is there to protect the cable. I think you can fit 16mm cable. You dont need to use that size, this data sheet looks like it might help with cable length and size. The fuse needs to be less than the cable current capacity.
I would probably use 8awg with a 30A fuse. See what you think, maybe others have some better opinions.
E_D_BS_Cable-Size-Chart_REBRAND-2024_V1.1 (1).pdf (178.7 KB)