Separate 110v 15a shore power

[Arthurc]

Hi,
Has anyone added a dedicated 110v shore power connection to a boat that normally uses 50a. There are a number of docks I go to that power can be hard to come by during the busy season, was thinking a dedicated charger maybe 12v/40a or 50a could keep up with my use and allow me to use a standard 15a outlet.
Boat has 1600ah of agm and a xantrex freedom 3012 inverter/charger. My average amp usage is about 30-50 depending on what’s on such as when the boiler flips on.

Any thoughts or advice would be appreciated. I’ve considered solar but don’t have enough room to keep up with demand, especially in the pnw.
Thanks!
Arthur

 

[psneeld]

Why not a 50 to 30 then 30 to 15 adapters?


I have done it on my boat numerous yard periods.

 

[Sealife]

Agreed, then just program inverter/charger with max incoming amps, and let it do it’s thing. Mine will invert when over value, and charge when under.

 

[diver dave]

Yeah, i agree. Especially since it might also mean yet another transfer switch to install OR a manual plug swap from the charger feeder.

 

[Arthurc]

Ive done that a few times but remembering to set the profile and then to switch back is a pain. The other risk is 110v outlets don’t usually have breakers near them so if you do try and pull 30+a on that leg you might not be able to reset the breaker. I wonder if anyone makes an in-line 15a fuse.

 

[psneeld]

If talking using only DC on the boat when plugged into 15A shore power, and letting your inverter run the DC side...and the max is 50A DC, then no worries on a 15A shore power lead.

 

[tiltrider1]

What I have done is added a 120v 15a inlet that is wired to a 15a stand alone breaker that is wired to a 40a battery charger with the charger being hooked to the main bank. When plugged in the battery charger charged and when not plugged in nothing. Back in the day Public docks had no power but there was always a light pole some were with an outlet that we could plug into.

We also did something similar with a 220v inlet and battery charger for boats headed to the land of 220v.

 

[rslifkin]

With only 15a power available, I often don't even bother plugging in. It's enough that I can run a battery charger *or* the water heater *or* the coffee maker and not much else. But if I have to, I don't power the L2 side of the panel and I flip any un-needed breakers off first. If I really wanted, I could run the inverter/charger in invert only mode and close the breaker that links the 3rd output of my engine bank charger to the house bank and let that charger be the only AC draw.

 

[Arthurc]

I should be fine with 15a ac driving a 50a 12v charger as the inverter will take up the slack when the draw is higher and I can use the boiler for hot water. I like the idea of a dedicated charger and inlet.

 

[MYTraveler]

I have adapters for that purpose, but the limited amperage means I can't run much more than the battery charger anyway. My boat has a backup charger that, conveniently, plugs into an engine room outlet. It is a simple matter for me to plug into an extension cord connected to the dock, and then run the boat off the inverter.

 

[OldDan1943]

Run an extension cord to the boat to keep the batteries up. Run a coffee pot, unhook the charger and run the pot.

There are many adapters available. When I bought this 30amp boat, I loaded up with many adapters.
Get a couple of Y adapters to feed your boat. The dock has a 50amp plug, I put in the Y adapter to run 2 30amp cords. I have an adapter for 50 amp to 115vt.
I find it easier to just run an 115vt extension cord from the 115vt outlet on the pedestal to the boat. The pedestal should have a 115vt breaker but, you can built your very own breaker too.
Of course I do have a couple of solar panels so that keeps the batteries up.

 

[diver dave]

But solar no workee in Seattle.
[emoji848]

 

[OldDan1943]

But solar no workee in Seattle.
[emoji848]

bummer. Time to move south?

 

[tiltrider1]

What Arthurc is trying to avoid is reprogramming his inverter every time he uses an adapter. He could run an ordinary extension cord from the dock to his backup battery charger but that would require fishing the cord through the cabin or through the engine vent each time. What he is thinking of doing is a very standard practice when it comes to converting 110v boats for 220v usage.

 

[SteveK]

Recently I programmed my inverter for 30 amp input as that is the main feed. But then I realized the inverter is fed by a 15 amp breaker. Programmed to 15.

So if I were to plug into 15A shore no need to reprogram.
Do others have inverter direct to shore cable?

 

[rslifkin]

Recently I programmed my inverter for 30 amp input as that is the main feed. But then I realized the inverter is fed by a 15 amp breaker. Programmed to 15.

So if I were to plug into 15A shore no need to reprogram.
Do others have inverter direct to shore cable?

My inverter has a transfer switch rated for 50A and is wired to handle passing a full 50A through. So my inverter input is wired right to the L1 main breaker. Output goes to an inverter sub panel. So my 120v panel is in 3 groups: L1, L1/Inv, L2.

 

[Seevee]

When I added my charger/inverter I ended up with a spare ProMariner charger. Wired a 110v/15a plug to the side of the boat and used an extension cord. It has a breaker in the panel. Dirt simple to install, and run the wires and is very handy and worked well instead of hauling a heavy 50a cord around.



Easy to keep the batteries topped, and run a number of items off the inverter. Very glad I did it.

 

[OldDan1943]

I have a 115 to 30amp adapter. Plug into the boat.
My inverter is set up with switches allowing me to put the galley 115 outlets and the microwave on the inverter. I still have to be careful and watch the the battery buss voltage. My inverter is 2K and have 3X4D batteries for the 'house' loads and a 40amp battery charger. The inverter can suck down the battery voltage down quickly..... Increasing the size of the inverter would do me no good because I do not have the batteries to support it. SHRUG
Gotta learn to live within the limits of the house battery bank capacity, the inverter capacity and the capacity of the the battery charger ..... and the 30amp dance. I do have an electric oven and 3 burner electric stove. If I had as gas stove, I would 'in hog heaven' when it comes to a 30amp boat. I make no apology, I rather have an electric stove.

 

[twistedtree]

Is the boat normally 50A 120V, or 50A 120/240V? It makes a big difference when it comes to using 30A 120V as a power source.

 

[diver dave]

Recently I programmed my inverter for 30 amp input as that is the main feed. But then I realized the inverter is fed by a 15 amp breaker. Programmed to 15.

So if I were to plug into 15A shore no need to reprogram.
Do others have inverter direct to shore cable?

Something i am missing. What does “programming the inverter” do?

 

[Seevee]

FWIW, on my new boat (MS 430), it's a 50a 110/220v supply, I have a 30 amp adapter that has a jumper that puts the two 110v legs (L1 and L2) together, and use a 30a 110v shore power to supply the power.


The whole boat is powered, but only has 30amps overall, and no 220v capability. So I cant run the 220v stuff which I see no need for at the dock anyway.



I just have to monitor things because of the 30a limit, however, for normal ops, (charging the battery, fridge, dehumidifier and perhaps a light or two) it's way more than needed.


As for programming the inverter in any situation.... no need. Makes no sense. What am I missing?

 

[rslifkin]

If you've got an inverter with a really big charger, you may want/need to turn it down when on a low amp shore power supply. Otherwise, if you plug in with low batteries, it may suck up all of the power or trip the breaker.

 

[OldDan1943]

The whole boat is powered, but only has 30amps overall.
I just have to monitor things because of the 30a limit, however, for normal ops, (charging the battery, fridge, dehumidifier and perhaps a light or two) it's way more than needed.

Yea, my AT34 is a 30amp boat and I have an electric stove and oven. I went so far as installing an amp meter in the galley area to monitor and assist in my "30amp dance" when cooking . First load to shed is always the water heater.
I have an 1800 watt inverter, I consider that a nice addition. The icing on the cake are the 2X130(?)watt solar panels.
If one starts upsizing the inverter remember, you must have the batteries to support it. I have 3X4D for house batteries, 1X4D for start battery.
I can leave the boat and the solar panels charge the batteries to support the 12vt fridge and bilge pumps.
The inverter..... that's another story. I have switches so I can put it to the microwave (limited cooking time, watch the house battery voltage) OR the 115vt outlets in the saloon, gotta make the coffee.

 

[tiltrider1]

Something i am missing. What does “programming the inverter” do?

Since there are so many different types of inverter/charges this could mean several different things.

In many cases an inverter/charger distributes power between the house and charging batteries with house having highest priority. The Inverter needs to know how much shore power is available so that it doesn’t pop the breaker. Some inverter/chargers also supplement power. Meaning if you have 30amps but the house needs 50amps it will supplement by taking 20amps from the battery to add to the 30amps from shore.

 

[SteveK]

Something i am missing. What does “programming the inverter” do?

you set the input amp available so it knows how to share flow through. I guess it will avoid blowing breaker. This is a setting with the SCP on Xantrex. Default is 30 amp. My inverter feed is 15A breaker off a 30A main.

The charger operates on 80% of breaker. If left set at 30 amp default it expects 24 amp used before it reduces charge output and gives back current to loads.

 

[ksanders]

On our Victron inverter/chargers setting the inverter to an amperage limits the AC current through the inverter to that value.

If loads on the inverter exceed that value then the inverter draws on the batteries to supply the loads.

Not all inverters support this, but I thought the Xantrex SW series the OP has do.

 

[SteveK]

but I thought the Xantrex SW series the OP has do

Had to read the manual, yes it does have that ability IF you have a generator and AGS (auto gen starter) installed and gen enabled. Could not find shore power assist and suspect that may be due to the bonding of neutral/ground conflict.

 

[diver dave]

...Some inverter/chargers also supplement power. Meaning if you have 30amps but the house needs 50amps it will supplement by taking 20amps from the battery to add to the 30amps from shore.

Thats interesting. It would then have to phase and frequency lock its ac output to shore power.

 

[MVDarlin]

Use a 15 amp adapter. Easy to make with an extension cord and 50 amp plug.