Solving Electrical Routing Issue - Planning Stage

[Cloroxbottle]

Started out with a 12V boat with two gasoline outboards and a lithium house bank and a starting battery with a battery isolater and the two tied with a 3 position switch. The existing inverter/charger was functioning as a charger, the inverter function was inop. AC in for this was 120VAC, a standard 3 prog plug + extension cord. The inverter out ran to a rotary selector switch that allowed you to switch from shore power to generator (long size removed) an was conected to the generator side.


My plan: Connect 30A shorepower through an ELCI to a new 1200W inverter charger that was connected to the house bank, and to the main AC disconnect on the main electrical panel allowing it to handle the passthrough and select how the AC panel would be powered.


The "pro" I hired for the AC work basically refused to do this despite telling him that our highest AC loads would be 750 resistive, 400 inductive, and 200-250 inductive none of which would be used at the same time.


He hooked the shorepower up through the ELCI and directly to the main breaker on the AC, basically removing the batteries and wiring for the house bank in the process. Also, the routing put the shorepower cable between the plug and the ELCI at risk of chafing through. After getting a call saying that the house bank was shot and needed to be replaced (I declined) followed by another call 10 minutes later saying it was fine (among other things) I terminated that relationship. Lesson learned.



So I have to fix this. With the house power basically uninstalled and the boat disabled I decided that this was a good time to move ahead with an electric repower.


48V batteries and their chargers are going to be split between a compartment (starboard) where the house bank and wiring once lived. It will not be tied to the 12V system which I will move under the settee.


The problem now comes in what to do with the AC shorepower once I fix the physical cable routing and finish the ELCI installation.


The current combined AC/DC panel is full, and has no room to add additional AC/DC breakers.


But two 48V battery chargers and the 12V inverter/charger still need to be installed.


Option (1):


Run shorepower from the plug to the ECLI and on to a
Blue Sea Systems 1214 120 Volt AC Main + 2 Positions

Connect the 48V charger to the two distribution breakers on that panel and From run the shorepower to a
Blue Sea Systems 8077 AC Main, 30A

that will be able to isolate the AC in of the inverter and on to the inverter charger. Connect the AC out of the inverter charger to the main AC breaker on the existing panel.


Option (2):


Run shorepower from the plug to the ELCI and on to the main AC breaker on a
Blue Sea Systems 8409 AC Main + 3 Positions

Then use three of the distribution breakers to power the two 48V chargers and the AC in of the inverter/charger and run the inverter charger output to the existing main AC breaker on the existing power panel.


Option (3): Something else?

[Turtle Blues]

I always worry about someone not familiar with the boat needing to shut down something in an emergency or situation where I am not aboard. This would steer my vote to option #2 as being more intuitive /quickly understandable.
Also have a preference for digital display over analog. If you contact Blue Sea, they have panel fabrication to your specification capability.

[Cloroxbottle]

Agreed that this is probably the "cleaner" solution.


The only disadvantage of this is that the AC provided to the inverter/charger would end up being routed through a 15A breaker where in option 1 a full 30A (probably limited to 25 or 20 through dip switches) would be passed on to the inverter/charger.

[Turtle Blues]

True. I would ask them about switching one of the sub breakers to a breaker sized for the inverter.
Not sure how big the cost increase is when you start asking for modifications. may be more economical to just purchase and switch out the additional breaker.

[Cloroxbottle]

Buying the stock panel and swapping out the breaker is what they suggested. Seems easy enough. The only question now is that the inverter is dip switch selectable for 15 (default), 20, 25, and 30 amps. What to pick and what size breaker to substitute in.

[Turtle Blues]

Sounds like the limiting factor will be the single 30A/120v coming in, which will be protected by the 30a main breaker.
Next question is total AC load on the existing panel.

If the 3 values you give in 1st posting are wattage on a single circuit, the cumulative load is within a 15A breaker.
I am confused when you list the multiple amp settings for the inverter. A 1200w inverter is 10A. Selectable higher settings suggests the capacity is much more than this.
Finally 48 volt chargers range from 120v plug in to massive power supplies. Need to better understand what is required.
Probably helpful to make a ladder drawing of the entire system.
Suggest you look at some of Jedi's postings. He is a wizard at schematics and power distribution design.