One of my AC chargers recently began having problems, so instead of buying another one, I was considering rewiring my electrical system a bit to do a couple of things. First would be to rewire it so that i could make use of the single remaining charger for everything. The second thing is to rewire my electrical system so that i could plug into shore power anywhere in the world without having to make any special modifications.
I know the way to do this (at least one way) is to wire the shore power directly to a battery charger that charges the house bank that has an inverter connected, and then run all the AC loads through the inverter. Thats simple enough to do and to wire up, however I would also like to be able to send the shore power directly to the AC distribution panel when i'm in the U.S. home port and to not use the inverter for my AC loads bypassing it completely. To do this I envision using two Blue Seas 9009 rotary switches.
In the attachedwiring diagram crude drawing, on the left is the shore power inlet, from there (omitting circuit breaker, galvanic isolator etc etc...for simplicity) it goes to the first rotary switch as the only input. From this rotary switch i can choose to send it to either one of two outputs, the battery charger/house bank/inverter branch or to a second rotary switch. The second rotary switch accepts two input sources but only allows one of the two sources to go to the AC distribution panel. The second source is 100% isolated. If i chose to send the shore power directly to the AC panel I would switch the first rotary switch so that it sends AC directly to the second rotary switch, from the second one I would simply choose that source as my AC.
Now, if i was sailing somewhere where the shore power was different from the US, I would do the opposite, I would switch the first rotary switch to choose to send the AC power to the battery charger/house battery/inverter branch. From here I would turn on the inverter for my AC loads and select the inverter as my power source on the second rotary switch sending the inverter AC to the AC distribution bus.
I can not find a fault with my wiring diagram so far, but its getting late and am tired so might be missing something obvious. Because the second rotary switch only allows a single source to get to the AC panel, i'm not seeing any back feed issues with the inverter. I could have the inverter on and the shore power going to the same rotary switch (#2), but both would be completely isolated at the switch. The charger would also be on an isolated circuit breaker so it could be switched on/off manually.
I would have to buy a DC-DC charger, but they are much cheaper than a decent AC charger. Also with this arrangement, my bilge pumps could be connected to the house bank. When out sailing they would have plenty of power to draw on from the lithium batteries. When plugged in at the dock they would have unlimited power to draw on and also work if there was a shore power outage. It seems to simple though so i feel like im missing something obvious.
I know the way to do this (at least one way) is to wire the shore power directly to a battery charger that charges the house bank that has an inverter connected, and then run all the AC loads through the inverter. Thats simple enough to do and to wire up, however I would also like to be able to send the shore power directly to the AC distribution panel when i'm in the U.S. home port and to not use the inverter for my AC loads bypassing it completely. To do this I envision using two Blue Seas 9009 rotary switches.
In the attached
Now, if i was sailing somewhere where the shore power was different from the US, I would do the opposite, I would switch the first rotary switch to choose to send the AC power to the battery charger/house battery/inverter branch. From here I would turn on the inverter for my AC loads and select the inverter as my power source on the second rotary switch sending the inverter AC to the AC distribution bus.
I can not find a fault with my wiring diagram so far, but its getting late and am tired so might be missing something obvious. Because the second rotary switch only allows a single source to get to the AC panel, i'm not seeing any back feed issues with the inverter. I could have the inverter on and the shore power going to the same rotary switch (#2), but both would be completely isolated at the switch. The charger would also be on an isolated circuit breaker so it could be switched on/off manually.
I would have to buy a DC-DC charger, but they are much cheaper than a decent AC charger. Also with this arrangement, my bilge pumps could be connected to the house bank. When out sailing they would have plenty of power to draw on from the lithium batteries. When plugged in at the dock they would have unlimited power to draw on and also work if there was a shore power outage. It seems to simple though so i feel like im missing something obvious.
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