Switch panel

[FilterGuy]

Would I need to have a positive and neg busbar or could I use the neg on the fuse block?

Hmmm.. There are 4 things on that bus Bar. The Battery, the SCC, the Inverter and the Fuse block.
The inverter and the charger are rated at higher amperage than the Fuse-block can handle so those can't go through the fuse block. The *proper* way to deal with it is a bus bar. Having said that.... You have 3 'large' connection points: 1)The battery, 2) the inverter and 3)The large common negative on the fuse blocks. If you can hook all 4 items together without more than two lugs per connection, you might be a be able to make it work.
(I recommend the bus bar).

Also would fuse #2 be a 30 amp? Or how do I calculate that? Would that be a calculation of the appliances all together?

The box is rated 30 amp per connection and the individual circuits are protected by breakers at the switch box. So, yes 30 amp fuse is what I would use, but make sure the wire to the switch box can handle 30 amps.

 

[FilterGuy]

The box is rated 30 amp per connection and the individual circuits are protected by breakers at the switch box. So, yes 30 amp fuse is what I would use, but make sure the wire to the switch box can handle 30 amps.

You should definitely do two things:

1) Find the ratings on breakers on the switch panel. Hopefully they are 30 Amps or under. If not, we may need to do something different.
2) Add up the max current for all of your 12 volt appliances. (I am guessing you will be well under 30 amps.... but you should check) If it is greater than 30 amps, you may need to split the switches into a couple of circuits in order to keep the current under 30A. If you do need to split the circuits, it would be something like this:



Also, remember that if the fuse box is not right next to the positve bus bar, the wire to the fuse box must be able to handle the current of the main fuse, or there should be a fuse at the bus-bar end of the wire going to fuse block.