Shore power relocation

[pas63]

I have an anchor locker at the bow of my boat. The boat is a 35’ center cockpit sailboat. For some unknown reason the manufacturer thought this a good place to mount the shore power (240v 50 amp) connection. If I dock stern in, I’m looking at 35’’ of shore power cable just to get to the stern. My breaker panel is roughly midship on the stbd side. I’d like to move this out of the anchor locker and am very limited on other locations. I see three options.

1. Mount it on the port side stern. The hood is a deep locker on the port side stern puts storage for the cable right at hand. The downside is wiring would have to run across the transom then forward on the stbd side to the breaker panel.

2. Mount it a few feet forward of the breaker panel on the side of the cabin top.

3. Right behind the breaker panel is my propane locker. I have room in there to mount the shore power. This keeps the connection the most protected and only needs a few feet of wire to the breaker panel.

I am open to any other ideas.


The following is a brochure on the boat. https://boatbrochure.com/products/s2-35c-brochure

[Jammer]

The problem is that you're running 50 amp shore power and the cables are big, heavy, and expensive. Unless you actually need 50 amps for something (electric range? dual air conditioners?) my advice would be to switch out the 50a breakers for a single 30a breaker and switch the shore power connector from 50a 120v/240v to 30a 120v.


By comparison, 30a shore power cords are light, flexible, cheap, and compact, and are readily available in a 50 foot length which should be plenty to reach most pedestals even if you're docking stern-in. Or you can make a longer one by ordering the cable and the ends.

[JoeRobertJr]

Option 4: Always moor bow in.

If you are committed to relocating your shore power plug, your #2 and 3 appeal to me the most. For me, it would be about keeping the installation as simple and easy as possible, so figuring out exactly where the new plug/outlet would mount and where the wires would run.

Other considerations:
- Where to mount the breaker that you want as close to the outlet as possible. Is there already one in the anchor locker that you plan to relocate?
- Switching to a Smart Plug for the boat end of the shore power cable.

[ItDepends]

For a S2 center cockpit do you REALLY need 50 amp service???? Maybe you are only using one leg of the split phase? Or is your boat wired for 220V in the cabin? (Which would be very odd for an American built boat)

[Nekton73]

Another option... leave the existing shore power in place, install a new 30A connection at one of your other potential locations, add a switch at your breaker panel so you can select which one you wish to draw power from. This leaves you the flexibility to connect shore power no matter which way you come in to the dock, and the option to have the 50A connection if really needed.

[pas63]

Originally Posted by Jammer

The problem is that you're running 50 amp shore power and the cables are big, heavy, and expensive. Unless you actually need 50 amps for something (electric range? dual air conditioners?) my advice would be to switch out the 50a breakers for a single 30a breaker and switch the shore power connector from 50a 120v/240v to 30a 120v.


By comparison, 30a shore power cords are light, flexible, cheap, and compact, and are readily available in a 50 foot length which should be plenty to reach most pedestals even if you're docking stern-in. Or you can make a longer one by ordering the cable and the ends.

I ran dual 30's for many years and got tired of frying one or both trying to stay warm in MD winters. I'm in FL now, probably not as critical since I don't need to augment my HVAC. That said, 30 or 50 amp presents no difference on the original question - where to mount the shore power connection.

[Nekton73]

Ok then,


my personal choice would be mount a new 50A at the stern location then. I prefer not having cable laying on or over the deck if possible.


I would still leave the original shore power and install the selector switch at the panel. Now I have two options, no worries about amps or phase difference.

[pas63]

Originally Posted by JoeRobertJr

Option 4: Always moor bow in.

If you are committed to relocating your shore power plug, your #2 and 3 appeal to me the most. For me, it would be about keeping the installation as simple and easy as possible, so figuring out exactly where the new plug/outlet would mount and where the wires would run.

Other considerations:
- Where to mount the breaker that you want as close to the outlet as possible. Is there already one in the anchor locker that you plan to relocate?
- Switching to a Smart Plug for the boat end of the shore power cable.

I converted from a single 30 to dual 30's as a single could not keep the boat warm in MD winters. About 8 years ago I relocated my breaker panel, installed a custom Bluesea panel and switched to 240/50 amp. During the winter I could run HVAC, water heater, dehumidifier and a couple space heaters with no issues.

[pas63]

Originally Posted by ItDepends

For a S2 center cockpit do you REALLY need 50 amp service???? Maybe you are only using one leg of the split phase? Or is your boat wired for 220V in the cabin? (Which would be very odd for an American built boat)

In MD yes, I needed 240V/50. Now in FL probably not, but I see no need to go back to 30's. Regardless of which the relocation question remains the same.

[Shrew]

Originally Posted by Jammer

The problem is that you're running 50 amp shore power and the cables are big, heavy, and expensive. Unless you actually need 50 amps for something (electric range? dual air conditioners?) my advice would be to switch out the 50a breakers for a single 30a breaker and switch the shore power connector from 50a 120v/240v to 30a 120v.


By comparison, 30a shore power cords are light, flexible, cheap, and compact, and are readily available in a 50 foot length which should be plenty to reach most pedestals even if you're docking stern-in. Or you can make a longer one by ordering the cable and the ends.

This really depends on how his panel is AC panel is set-up. If his panel is setup with a single 50amp feeding two 30amp panels, with 2 x 30amp breakers, going to a single 30amp in is not a great idea.

If the panel is a single 50amp breaker being fed by a 30a outlet and cord also doesn't make sense.

[Shrew]

OP. My boat has 2 x 30amp shorepower connectors at the bow and 2 x 30amp shore power connectors at the stern. I have a bypass switch similar to the (Shorepower/Generator) switch. I turn on inbound breakers for the bow and turn off the breakers for the stern outlets when I'm bow in. I reverse it and turn off the breakers to the bow connectors and turn on the breakers to the stern connections when I'm stern in.

Rather than moving your connectors, I'd add a second set of connectors in the stern. Router all shorepower connectors to bypass/isolation switches, then feed the main on the panel from there. This will be roughly the same amount of labor and give you flexibility.

[wrwakefield]

Our center cockpit ketch is also wired for (North American) 50A 240V AC (nominal), and has a shore power inlet on each side of the cockpit. We select the inlet that is most convenient to connect the shorepower cable to. [e.g., the side of the boat we aren't boarding from.]

The two inlets cannot be used simultaneously: there is a pair of circuit breakers with mechanical lockouts on our AC panel so only one of the two inlets can be hot. (i.e., the unused male inlet won't be hot and is therefore not a shock hazard should someone open the unused inlet cover. And both inlets are switched off when using internal AC sources like the generator or inverter- which is wired as another AC source; not an AC passthrough. i.e., UPS.)

When we don't need the 100A of 120V AC a 50A 240V AC service provides, we use a modified 30A shorepower cord [The 10 AWG, 3 wire 30A cable is much smaller and lighter than the 6 AWG, 4 wire 50A cable.]

The two mods to our 30A shorepower cable are a 50A connector (we use SmartPlugs) on the boat end, and the two hots are jumped inside that 50A connector (on the 30A cord that has only 1 hot...) so the entire AC panel is hot (albeit with only 30A 120V AC vs. the 100 amps of 120V AC we get when we use the 50A shorepower cord.)

If this doesn't make sense, please don't try it without consulting a marine electrician.

My two points being we can feed shorepower from either side of the center cockpit (which means cable length requirements off the bow or stern are about the same) and we can use either 30A or 50A shorepower cables depending upon our power vs. ease of (showepower cable) handling requirements.

In case any of this is of interest.

Cheers! Bill

[Jammer]

Originally Posted by pas63

I ran dual 30's for many years and got tired of frying one or both trying to stay warm in MD winters. I'm in FL now, probably not as critical since I don't need to augment my HVAC.

Your boat, your choices.

That said, 30 or 50 amp presents no difference on the original question - where to mount the shore power connection.

It does, actually. With 30 amp service it does not matter much because shore power cords are flexible and light.


With 50 amp service, the shore power cord is big and heavy and there's nothing much you can do about it, aside from running a 10 kw isolation transformer and making a custom 2-conductor shore power cord with no neutral and no ground, which is another can of worms.


I would not recommend mounting a shore power connection in the wall of the propane locker because it would be a fire and explosion hazard. Either of the other locations is fine. You'll have to run 4 conductor 6 gauge boat cable to it, which is available but costs $10 a foot.

[smac999]

No way I’d put ac inlet / wiring inside propane locker. It will ark / spark when connecting / discinnecting.

[boatpoker]

Originally Posted by pas63

3. Right behind the breaker panel is my propane locker. I have room in there to mount the shore power. This keeps the connection the most protected and only needs a few feet of wire to the breaker panel.

First time a surveyor sees that will get your insurance denied until corrected.
or a ... claim denied.