Battery System upgrade - add MC 618 / SG200

[Plumbean]

Don't know the answer to your question about the sense wire, sorry. On the 5196 from BlueSea, note that you have to use MRBF fuses on every terminal. I looked into using that fuse block for my always on busbar, but because I wanted to use a Class T fuse for my inverter I ended up using a standard busbar (2127 MaxiBus) and separate fusing (ANL for the Alternator and Class T for the inverter), while putting an MRBF fuse directly on the off-take from the battery.

[phantomracer]

Originally Posted by Plumbean

Don't know the answer to your question about the sense wire, sorry. On the 5196 from BlueSea, note that you have to use MRBF fuses on every terminal. I looked into using that fuse block for my always on busbar, but because I wanted to use a Class T fuse for my inverter I ended up using a standard busbar (2127 MaxiBus) and separate fusing (ANL for the Alternator and Class T for the inverter), while putting an MRBF fuse directly on the off-take from the battery.

Yes, I figure each wire should be fused, and it seemed elegant and compact to use that busbar. Not a lot of room in the battery box. Pretty much the reason I am looking at it. Just in the design phase now. anything can change! I do have the MRBF fuse on the house battery bank now.

Otherwise the new battery wiring looks halfway decent? I don't do this a lot, so I want to ensure I am doing it the right way. No ego bruised if I am wrong!

I THINK the sense wire will be OK, as long as the 618 doesn't turn on when the alternator disconnect is off. I just got a bit concerned me as there was a conflict between RC's site and the Balmar manual.

[phantomracer]

Did a little more fine tuning,


I think I may not (initially) need more than 2 MRBF fuses at the battery, and I have a 2 MRBF posts at the battery already. One is vacant, so I can use that fuse to go to the alternator wire.


I think I can get away with a Blue Sea 5052 reset only breaker block for the small gauge wires for the 618 sense, sg200, and duo charge.


Put more detail in the diagram, and moved a lot around, I think it is a lot easier to read now!

Only thing I didn't change in the layout yet is using the neg bus on the 5052 for the neg wire of the 618. I might just put it to the battery terminal instead.

So, if I have it right, the 618 and alternator won't turn on if the alternator disconnect switch is off. I can start the engine form either battery bank if needed. The sense wire should give better readings

Now the fun part...fishing and running wires all around a 54 year old boat, not designed for any of this!! Should be a fun project!


Again, any comments are welcome!