Adding electrical connection at other end of boat

My Mariner 37 has two 30 amp SmartPlug connections on the transom to starboard. That's fine when tied stern, but awkward when bow in. Our inverter/charger and main panels are amidships. What is involved in adding a second connection at the bow?

And what issues surround deciding between two 30s and a single 50 amp connections?

Just a lot of wire and breakers... 50a shouldn't be an issue either as long as you dont overload it and properly size the wire for the runs...
We have 2x 50a 125 bow and cockpit. They could have just done dual 30's but went up for some reason.

One thing my boat doesn't have that I am still contemplating adding at some point (#978 on my list of 1000 things to do on boat). There is NO selector switch or accessible breaker so that I can turn off one or the other (very odd). So technically if I am on shorepower and you are stupid enough to stick your fingers into the boat outlet that's not being used, you WILL get woken up REALLY quickly!!!

The physical installation of the marine SmartPlugs seems pretty straightforward, as does the selecting and running the wire. It's the integrating of that power into the rest of the boat circuitry that gives me pause. This is all still new to me and I plan to spend a day with a certified marine electrician this Spring. Looks like a new connection at the bow will be on the agenda.

I'll need to dig through some old stuff I have, but it's fairly easy to do. You're just going to terminate at the same location you are already at, at the panel. Your panel should already have a breaker for existing power. This may be a good time/place to split the wiring at that breaker and have one for bow, one for aft. You will also need a break within 5' (I believe that's the rule) of the inlet as well...

The setup on Scottwb96's boat is non-compliant with ABYC Standards and, as he states, is unsafe.

Assuming that one shore cord supplies the house loads and the other supplies the air conditioning systems, a relatively simple mod is to install one of these https://tinyurl.com/y4hvcxs5 for each load center. Or, install two of these: https://tinyurl.com/yxkq2nk9

Your marine electrician will be valuable in determining the best course of action. The most time consuming and difficult part of the job will be running the new cable from the forward shore power inlet location back to the panel board.

Good luck.

Charlie,

NO CLUE what they were thinking when that was put in. My understanding is that it came that way from the "factory"!!!

ok, ok, ok, maybe I'll bump it from #978 on my list to something like #482...

Scottwb96

ABYC requires breaker for both hot & neutral within 10 ft of each inlet.
You also need the selector sw as CharlieJ indicates.

Why go to 50A? Unless you need the additional amps? Need to redo stern inlet, breakers & buy new 50A cords $$$$

2 30A inlets $ on bow would allow using existing cords

Bacchus said:

ABYC requires breaker for both hot & neutral within 10 ft of each inlet.
You also need the selector sw as CharlieJ indicates.

Why go to 50A? Unless you need the additional amps? Need to redo stern inlet, breakers & buy new 50A cords $$$$

2 30A inlets $ on bow would allow using existing cords

Click to expand...

Plus 1. You do need a selector switch on each 30 amp inlet so the unused inlet isn’t powered when not in use. There needs to be a breaker within 10’ from the inlet on each inlet. Also the breaker needs to be a two pole breaker.

CharlieJ said:

The setup on Scottwb96's boat is non-compliant with ABYC Standards and, as he states, is unsafe.

Assuming that one shore cord supplies the house loads and the other supplies the air conditioning systems, a relatively simple mod is to install one of these https://tinyurl.com/y4hvcxs5 for each load center. Or, install two of these: https://tinyurl.com/yxkq2nk9

Your marine electrician will be valuable in determining the best course of action. The most time consuming and difficult part of the job will be running the new cable from the forward shore power inlet location back to the panel board.

Good luck.

Click to expand...

Thanks Charlie. A consult with a marine electrician will most likely land him with the entire job. Loads on my two mains are divided, but not into house and air conditioning. The secondary panel makes a ton of sense. My boat has a sub-panel with breakers for each AC line in, but the panel must be bypassed as the breaker switches change nothing. Each line in is also broken at the main panel.

Suffice it to say, I am ready for professional help! Thanks guys.

Bacchus said:

ABYC requires breaker for both hot & neutral within 10 ft of each inlet.
You also need the selector sw as CharlieJ indicates.

Why go to 50A? Unless you need the additional amps? Need to redo stern inlet, breakers & buy new 50A cords $$$$

2 30A inlets $ on bow would allow using existing cords

Click to expand...

No good reason, unless I ended up making enough electrical changes to warrant changing the stern connections to 50 amps as well.

If you can having both socket positions powered will allow its use as a "buddy plug" should you raft with the noisemaker on.

No an accepted or safe practice to power male connection and make up non std adapters!
Beware is all I will say!
There are safecways to provide a connection but it will take $ and require more equip.

FF said:

If you can having both socket positions powered will allow its use as a "buddy plug" should you raft with the noisemaker on.

Click to expand...

My objective is solely to make electrical connections in bow in slips more practical.

Here's the situation, though I expect stuff like this is pretty routine as one cruises. My slip has an angle at the finger dock that means I can only get so far in with the stern. No problem when the dinghy is hanging on our St. Croix davits as we need the space back there, but that means the dinghy is "trapped" in the slip.

Bow in means access over the gunwales amidships, but it also means ready access to the dinghy. What am I missing?

Might be more practical to just get a longer shore power cord....I’m not usually one to “cheap out” on solutions, but also try to avoid overly complicating things on a permanent bases for what could be temporary problem.

Bow in also gives more privacy from dock walkers and lookey Loos .

And we are at the beginning of our cruising life. I expect many bow in moorings in the future. Seems like a worthy value to me.

FF said:

Bow in also gives more privacy from dock walkers and lookey Loos .

Click to expand...

Exactly why we back in. We like our dock neighbors and love sharing stories with them. Bow in We never get to chat.
BD

How close are you to maximum load on your 30 amp power cords?


I went from dual 30's to a single 50 on my last boat. We were always fine out our home marina with good outlets but we would inevitably scorch a plug or two when traveling due to less than perfect shore power plugs. When traveling I would use my 50 to two 30 splitter, if possible, to protect my 30 amp power cords.


Note: each 30 is nominally 30A x 120V = 3,600W x 2 = 7,200W
The single 50 is nominally 50A x 240 = 12,000W


The flip side of the issue is how many slips won't have 50 AMP power? You will need a smart Y converter to go from dual 30 up to 50.



We would always trip the house side of the 30 in the morning.
Wife - Shower (water heater), Cup of coffee and hair dryer > 3600 watts

We have never been close to maxing out two 30s and I think we would be fine with a single 50, but 30 am services seem more common in my limited cruising and the flexibility is important. I do have a 50x30 adapter and expect to have a 50x30x30 splitter soon.

Would it make sense to move the current connection point to amidship?


The only advantages I can see to dual 30s is being able to split the loads (lots of boat builders put most loads on one 30A while the other's only loads are the air conditioning units. It would certainly save you some money in some marinas where either 50A is not available at your assigned slip or where they charge more for 50A versus 30A.

Amidships would certainly make more sense than one end or the other. Guess if I am cutting holes and running wire, it might make sense to cut them amidships instead of having two sets to manage and maintain. Interesting idea.

Dual Shore Power Sockets

HeadedToTexas said:

My Mariner 37 has two 30 amp SmartPlug connections on the transom to starboard. That's fine when tied stern, but awkward when bow in. Our inverter/charger and main panels are amidships. What is involved in adding a second connection at the bow?

And what issues surround deciding between two 30s and a single 50 amp connections?

Click to expand...

My Mainship has (factory) Fwd and Aft receptacles, 2 ea 30 amp at both sites. There is a local breaker at each receptacle, and then a breaker for each receptacle at the panel; those 4 on the panel have sliding lock plates so fwd and aft cannot be ON simultaneously. There is also a Galvanic Isolator for each set of receptacles.
I consider these ingredients essential for safety, especially for reliable operation on long-term shore power.

That makes sense, McDan. My approach would be just like that.

It is really not a big deal to add another X2/30A to the bow safely. in my opinion, the worst part is running the heavy Gauge wires (for x2/30A) from the bow to a new panel dedicated for selecting Bow or Stern connections, reroute your stern wiring (x2/30A) to new panel, then connect the new panel to existing panel. My MS390 has Breaker as well at each end by the bulkhead connectors (ABYC Standards).
material;
-Two Marinco 30A bulkhead connectors.
-Two weather tight 30A breakers (w/protective caps).
-Sub panel to switch connections (stern/Bow).
-Heavy wire for appropriate length.
-A skinny Guy/Girl to run the heavy wires.

DrissZougari said:

-A skinny Guy/Girl to run the heavy wires.

Click to expand...

Hehe, that's probably the most difficult part!

i`ve always thought there should be an AC connector in good places on both sides, not for and aft!...clyde

That's a good point, Clyde. Guessing connections amidships would solve lots of distance to power issues. Certainly having them on both sides would reduce line clutter.

I need to get aboard and poke around to see where the practical points lie.

When contemplating shore power , remember at times you may be reduced to 15A/120v and need to survive with ease.

I have 30 x 15 amp adapter dongles that have let me run my inverter/charger when only 15 amp 120 VAC was available.