Does the DC Main on the Distribution Panel Provide the Same Function as the Battery Service Disconnect?

Question:

I’ve watched your videos and studied your diagrams but I’m left with one question. Doesn’t the DC Main on the distribution panel provide the same function as the battery service disconnect if the house bank is the only source of power to this panel? (I’d like to use the current location of the existing ‘1-2-Both’ switch for the location of the Inverter/Charger service disconnect.)  I’m updating the DC distribution on my sailboat and am completely separating the battery banks. All wiring is properly fused.

The alternator, inverter/charger with it’s separate service disconnect, and the solar charge controllers are all connected to the batteries at the unswitched positive and negative bus bars. A Balmar Duo-Charge provides charging current to the starter battery which is connects the the two battery banks directly and through the negative bus bar. The shunts for the meters on the distribution panel and Victron battery monitor are located between the house bank and the negative bus. As with all things electrical, I’m confused. - John

Answer:

You are on the correct track. If all your DC circuits are run at the DC panel, then yes a DC service breaker at the DC panel can act as on/off battery switch.  BTW, just based on your email, you’re probably way better at electrical concepts then you think, well done for thinking of all of this.  - Jeff