Understand 220V electrical wiring on 40 Cruiser

[Krumelur]

I'm trying to make a bit more sense of the electrical wiring (220V) on my boat.
My shore power connector is located starboard and inside the cockpit locker there is a breaker box with two breakers.

Q1: Why are there 2 breakers and not just one? The total power allowed or possible would be 3,5kW (220V * 16A) and therefore I cannot make sense of the second breaker right there.

From there, wiring leads down to the 302 panel. On my panel, there is a main switch which seems to be an RCS (residual current device).
Then, there are three separate 16A breakers:
- Bathroom 220V outlets
- Hot water boiler
- Battery charger

Q2: The breaker for the battery charger also powers the 220V outlet on the 302 panel. Is this the default or did somebody modify it?

I'd like to hear what the setup is like in your boats so that I can make more sense of how it is supposed to be and possibly rewire things.
I can, for instance, imagine that one of the breakers in the locker is meant to be used for the outlet.

[sean c]

I had my 230 volt system re-wired last year following a fire caused by the wiring inside the cockpit locker and downstream of the circuit breaker. This was caused by a modification, I believe, when a 'connector' was installed in this wire and covered in heat shrink. The heat shrink has little thermal properties and the connector (loose?) caused heat which burnt through the fibreglass resin exposing the fibres. It suffocated inside the locker and this was the only reason my boat did not burn to the water line.
Check for any modifications to the conduit.
I am not an electrician.
There are three wires from the shore power socket to the 302 panel. Brown, Blue and Green/Yellow. The Brown and the Blue go through a separate breaker each. My original breaker was non compliant to current Australian regulations according to the electrician that rewired my boat. Both breakers need to trip together and the new breaker has a pin connecting the two handles. See attached photo and zoom in to see where the wires go.
My 302 panel breaker has the RCD and three individual breakers. The left one is battery charger and power outlet on the panel. Middle is galley power outlet and right hand one is boiler hot water system.
While I was reviewing my whole system it became obvious that the inverter 12 volt to 230 volt system had no RCD, only a breaker protecting the equipment but not the people. I installed a portable RCD out of this and then ran that to a power board.
Sean

[Happysailor]

I have the original circuit diagrams of the Bavaria 40 Cruiser for you as they are similar to the Bavaria 41 Cruiser.

[Krumelur]

This is great information. I will also modify the breakers to instead use a single dual breaker if this is not already the case.
I found that also all internal breakers on the 302 must be dual breakers unless the boat is using a a transformer to fully decouple the circuits (I have one of these installed on my Jacuzzi, which is a scenario somewhat similar to a boat)

https://www.yachtbatterie.de/de/230v-technik/wichtige-informationen.html