Electrical Redesign for Liveaboard

[Bill Roosa]

Perhaps transfer switch is the wrong term. correct me if I'm wrong but a combined IC would only need to sense AC to turn off the inverter and turn on the charger. In that mode it is just an appliance that charges the batteiries using AC. when the AC goes off it stops charging and turns on the inverter. And if there is a two pole breaker at the main AC you would not have iany interconnect.
So I'm thinking it is not a transfer switch in the normal sense but just an automatic mode changing switch.

 

[tristanperry]

I can't thank everyone enough for helping me with this endeavour, your patience is appreciated. I've tried my best to incorporate all of your ideas from other posts and posts in this thread, extra thanks to Maine Sail, Stu Jackson and Bill Roosa.

Here is a link to my revised design, based upon all of your recommendations. I'm really hoping I've got it this time! http://www.lucidchart.com/publicSegments/view/4f91a9bb-9480-4a73-9dff-66d70a60e9bc

 

[Bill Roosa]

I just went and read the freedom manual and these things are designed to either power seperate appliances or power a sub panel. They are fed from the AC main panel as a branch line.

 

[Stu Jackson]

Not necessarily, Bill. Wiring Option 1 shows the incoming shorepower to the inverter and then to the main AC boat panel. This is how I installed mine. As I mentioned to Brian, there ARE many different ways to do it.

 

[Stu Jackson]

Perhaps transfer switch is the wrong term. correct me if I'm wrong but a combined IC would only need to sense AC to turn off the inverter and turn on the charger. In that mode it is just an appliance that charges the batteiries using AC. when the AC goes off it stops charging and turns on the inverter. And if there is a two pole breaker at the main AC you would not have iany interconnect.
So I'm thinking it is not a transfer switch in the normal sense but just an automatic mode changing switch.

From the manual:

2. Automatic transfer switching between
inverter power and incoming AC power.

 

[mitiempo]

Stu is correct - there are several ways to wire the inverter/charger.

The first decision anyone has to make is whether they want the option of powering all AC with it or only a sub panel. The sub panel solution is the best as there would not be any way to leave a water heater or other high load device on and inverter powered. A water heater by itself will max the inverter output.

Either way there has to be a double pole 30 amp breaker as the first item the shore power sees. There is not any reason for a 30 amp double pole after the inverter.

The inverter/charger when on shorepower will pass through up to 30 amps of power to whichever panel it is connected to. When away from the dock it will switch to inverter mode.

The incoming hot and neutral have to be kept separate from the outgoing hot and neutral. This is easily accomplished with either sub panel or main panel installation.

If as shown by Tristan he is using the main panel only installation the shorepower hot and neutral go first to the double pole 30 amp breaker at the top of the main panel. Their outputs go to the inverter. The inverter output then returns to the main panel and feeds the 15 amp breakers for each circuit. The hot and neutrals are kept separate, green wire (ground) is common.

Bill
It works well either way, sub panel or main panel. In the sub panel installation the heavy load items like the water heater are only powered by shore AC, a 30 amp single breaker feeds the inverter and the sub panel takes its output. When on shorepower the sub panel is powered by the inverter pass through. The water heater etc are powered by shorepower that does not go through the inverter. The diagram from the Freedom 1800 HF manual showing this is below. The lead at the top is the chassis ground - which should be as heavy as the DC wiring.