Connecting Multiple Shore Power Cords

[tonyp444]

Hi all,

I’ve done a bit of reading on this but wanted to get your opinions. Our marina has permanent fixed (not floating) docks, and for multiple reasons I find it is much easier to get in and out of the slip, as well as board the boat, when we go in bow first. However, on our 325, the shore power inlets are located on the stern in the deck box, so it is a challenge to connect up our shore power with standard 50’ cords.

We have dual 30a AC service. One for air conditioning and the other to run all other AC powered accessories.

I’ve gotten by with running 50’ 30a cords down the side of the boat (secured to the railing) to this point, and thought there was enough slack in the cords to not be an issue, but we just had a particularly severe storm go through and the rocking of the bow yanked out both shore power cords from the pedestal. Not good. Now I’m very reluctant to run them down the boat and off the bow again.

I’m strongly considering running 50’ cords down our dock and connecting them to 25’ cords using sealing collars. I know this isn’t ideal, but it would give us plenty of slack and we could run the cords directly from the dock to the stern, so it would be so much cleaner and easier to manage. For what it’s worth, lots of other boats in our marina go into their slips bow first and connect two shore power cords like I’m suggesting.

To check the voltage drop, I tested out connecting two 50’ cords and I was still getting about 112 volts at the panel, which seems fine to me, and I think it would be even less drop at 75’ instead of 100’.

I’m not worried about the “accessories” breaker because the amperage draw is pretty minimal on that one. Mostly just running the refrigerator and battery charger, occasionally the TV, etc. It’s usually not more than a few amps. We almost never run the higher draw accessories like the water heater or electric stove.

I am worried about the air conditioning running on an extended cord since that is a much higher draw. Is this a bad idea? As long as I’m getting 110v+ and the connection isn’t hot, are we ok? I typically don’t run the air conditioning for more than an hour or two at a time, and I never run it when we are away from the boat. So I think the risk is pretty minimal, but I don’t want to do something stupid. I know it can be really hard on the air conditioning units if they aren’t getting the proper voltage. I thought about buying new 25’ and 50’ 50a cords for the air conditioner just to minimize the voltage drop, but they’re so incredibly expensive and I’m not sure it’s necessary.

Any guidance would be greatly appreciated.

[Midnightsun]

I do not see an issue. My "Travel" cord is 80' long. I custom made this just because when travelling to different marinas you never know how far the pedestal will be. (My permanent cable About 40') is fixed to the dock and remains there from spring launch to fall haul out. In my case I have a 250v 50a inlet connecting to a dual 30a pedestal with a reverse Y adapter. I run 3 AC units and everything else off of the 1 cord, no hot cables or issues whatsoever.

Lets take a 16,000 btu AC unit. This will draw less tan 10a when running BUT they do have a power surge when the compressor kicks in however this only last 5 seconds or so so not worth counting. Bottom line is your water heater draws more juice than the AC.

[tonyp444]

Thanks for the quick response, Hans. Really appreciate it!

[km1125]

Source of the post ...
To check the voltage drop, I tested out connecting two 50’ cords and I was still getting about 112 volts at the panel, which seems fine to me, and I think it would be even less drop at 75’ instead of 100’. ...

If you did this while the A/C units were running, then you'll be just fine with the 75' cables. (or even the 100' cables).

The water heater and range don't care at all about voltage drop getting to them... they'll just work a little slower under those conditions. And, depends on the actual fridge, but most of them won't care either because they just convert the AC to DC and as long as there's enough voltage at the DC point then it will work fine.

But definitely make sure NONE of the connections are ever getting warm. That means there's a bad connection at that point that needs to be addresses ASAP, because it's only going to get worse until it becomes catastrophic.

[g36]

I also am using and extension to my 50ft cord I also bow in and standard 50 ft won't get it.