Victron Multiplus Existing DC Wiring
With the inverter replacement, the relocation of the transfer switch, and all associated AC and DC wiring wrapped up, the next step was to review the existing DC wiring to make sure it would work with our new battery bay layout.
In the original setup — aside from the inverter wiring, which we’ve now replaced — there were several other connections running from the battery to different parts of the coach. These included the engine start boost switch, the generator starter, and the 120A breaker that feeds the battery disconnect switch by the front door (aka salesmans switch). Your setup may be completely different so be sure to check your schematics. Our details were found on print number B-2126 / Automotive Wiring Diagram.
The original inverter wiring was protected by a 350A T-Tron fast-acting fuse before running to the inverter. Since our new setup uses a 400A MEGA fuse housed in the Lynx Distributor, this original fuse was no longer needed and has been removed.
For the remaining circuits, we had two options: either feed them from the Lynx Distributor or directly from the battery disconnect. We chose to connect them to the battery disconnect. The main reason was that pulling power from the Lynx would route those loads through the 400A Mega fuse, and the actual current draw for the boost circuit and generator starter is both intermittent and somewhat unknown. In the original design, neither of these circuits was fused — similar to how the engine starter is wired directly from the starter batteries without a fuse.
We did leave enough cable in place for an easy switch to the Lynx if we decide to go that route later on. We could also add a in-line fuse to those locations if we feel that is necessary.
Similar to the engine compartment, the original installation used a single wall-mounted power post as the battery input point. From there, power was distributed to the inverter, boost circuit, generator starter, and the 120A breaker/disconnect switch.
Just like we did during the starter battery upgrade, the original single-lug distribution posts were replaced with BEP multipoint bus bars: BEP 650A 3-Stud Bus Bar for both the positive and negative connections.
This not only tidies up the wiring — especially on the negative side, where there were more lugs than you’d expect — but also improves the contact area, helping ensure optimal current flow.
