DIY Install threads for Victron MultiPlus-II and Li-ion Batteries

[Bigboote]

I am installing a Victorn package into my 2010 23FB.
At present 2 6g AWG cables run from the rather cluttered buss bars under the bed back to the DC (12v) fuse panel. Everything I read is that once i place in a Multiplus (I'll use the 2000W) i need 2/0 cables running from there to the 12V fuse panel. My hope is that I can use the exisitng wires to help me pull the 2/0 under the bed along with the necessary 6/3 and 10/3 for the AC side through the existing access to the start of the chase that goes across to the other side.
(tell me if I'm dreaming).
I am wondering how you connect the 2/0 wire to the fuse panel? The terminals seem like they would be too small to accept a wire of that size?

Any advice would be helpful.

[jnm30327]

I would suggest using the Victron Lynx DC distribution system for the DC distribution. For example:

1. Lynx Shunt for the battery connection - 400 amp fuse
2. Lynx Distributor for the DC Loads
a. DC-DC converter - 40 amps
b. Multiplus II - 300 amps
c. Airstream distribution box - 60 amps
d. Fuse block for miscellaneous loads at the front of the trailer - 50 amps eg trailer jack, Victron solar charger

You can see how I fused each of these in the attached picture. Your fuse sizes may vary.

[JeffKim]

Originally Posted by Bigboote

I am installing a Victorn package into my 2010 23FB.
At present 2 6g AWG cables run from the rather cluttered buss bars under the bed back to the DC (12v) fuse panel. Everything I read is that once i place in a Multiplus (I'll use the 2000W) i need 2/0 cables running from there to the 12V fuse panel. My hope is that I can use the exisitng wires to help me pull the 2/0 under the bed along with the necessary 6/3 and 10/3 for the AC side through the existing access to the start of the chase that goes across to the other side.
(tell me if I'm dreaming).
I am wondering how you connect the 2/0 wire to the fuse panel? The terminals seem like they would be too small to accept a wire of that size?

Any advice would be helpful.

If I understand correctly, you shouldn't need to replace the wire going to fuse box (ex-converter). The DC loads aren't increasing, so the existing wire should be good. I don't know the Multiplus, but wiring to the batteries I'd guess is something like 2/0.

[1957Custom22]

Unfortunately, you haven’t posted enough information to offer a definite opinion, but if your present set-up has a 6 AWG circuit from your DC power source to your fuse panel, AND all your 12 volt DC loads (lights, water pump, etc.) get their power through that fuse panel, AND you don’t intend to add any additional DC loads from that fuse panel, then there’s no need to change your 6 AWG circuit powering that fuse panel to a thicker wire size.

In that situation, the only circuit that should need the heaviest gauge (2/0 or thicker) should be the circuit between your new Victron Multiplus and your 12 volt trailer battery (or batteries). If the length of that circuit is over about 10 feet, you should consider going to an even thicker AWG, because DC travels poorly over distance. You can find charts online that can help you calculate AWG for DC based on distance.

[jnm30327]

FWIW. The Multiplus II manual calls for two 1/0 wires for the DC battery connection. I used two GC3 Battleborn batteries. I know many use a single 4/0 wire, but I opted to follow the Victron recommendation. Two 1/0 wires will carry more current than a single 4/0 (or 2/0)and also creates some redundancy. The 1/0 is also easier to bend. On the other hand, it doubles the number of lug connections needed. I got pretty good at making battery cables.

And second what JeffKim said. The wire to the trailer DC distribution box can remain the same.