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I have installed two 30A shore receptacles on my boat. The thought was that I could feed the shore power circuit with two 30A feeds-- either from (2) 30A sources or (1) 50A source through a splitter (eg Marinco 153AY or equivalent).

Spoke with the marine electrician that I have bought most of my stuff from and he indicates that it cannot be done. The 30A circuits must be separate and the leads cannot be aggregated at the shore feed of the (shore/gen/off) switch panel.

? So all these boats using two 30A cords have dual systems in the boat- one for each cord? So if a single cord is used- only that part of the AC system is hot.

So I need to toss the second 30A receptacle and add a 50A with a upstream switch to select one of those as my shore power source?
 

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We have a 50 amp to two 30 amp splitter and use it all the time when we are at docks that only have 50 amp outlets. You can buy these at Defender and several other places. Remember that not all 50 amp outlets are the same. There is 50 amp 125 and 50 amp 240. They are not interchangeable but there are splitters for both. I have both. Chuck
 

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Not sure what you're trying to do - combine two 30A inlets to feed a single panel?
Any boat I've seen with dual inlets typically has one for outlets, reefer, water heater, charger etc and a second for A/C (air conditioning, not alternating current). And yes, they are treated as two separate panels, or "sides" of the physical AC panel.

AFAIK you could then use a shoreside 50A-30A splitter to feed your two *separate* 30A circuits from a 50A dock connector, but keep the option of feeding only one side if only a single 30A is available (and giving up the A/C or whatever is on the second panel).
 

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We have a 50 amp to two 30 amp splitter and use it all the time when we are at docks that only have 50 amp outlets. You can buy these at Defender and several other places. Remember that not all 50 amp outlets are the same. There is 50 amp 125 and 50 amp 240. They are not interchangeable but there are splitters for both. I have both. Chuck
I do this, too. I have two 30 amp circuits in my boat, and I can't tell any difference between hooking it up to two 30 amp receptacles or using my splitter to hook it up to one 50 amp.

It hasn't hurt anything so far that I know of.
 

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I have installed two 30A shore receptacles on my boat. The thought was that I could feed the shore power circuit with two 30A feeds-- either from (2) 30A sources or (1) 50A source through a splitter (eg Marinco 153AY or equivalent).

Spoke with the marine electrician that I have bought most of my stuff from and he indicates that it cannot be done. The 30A circuits must be separate and the leads cannot be aggregated at the shore feed of the (shore/gen/off) switch panel.

? So all these boats using two 30A cords have dual systems in the boat- one for each cord? So if a single cord is used- only that part of the AC system is hot.

So I need to toss the second 30A receptacle and add a 50A with a upstream switch to select one of those as my shore power source?
Yes on board the vessel the two shore feeds must feed their own respective panels. Dual 30A feeds are usually done for adding AC or reverse cycle heat and that gets its own direct feed.

If you want to pass an insurance survey each 30A feed needs to go to its own panel..
 

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I may not be thinking straight but wouldn't pulling 2 30 amp circuits potentially pull too much for a 50 amp outlet?

Sent from my ADR6425LVW using Tapatalk
 

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One more caution:

Be VERY VERY careful when using a splitter such as the Marinco 152AY or 153AY to feed two 30A inlets from a single 50A shorepower plug. Each of these 30A legs is protected by a 50A breaker in the power post on the dock, NOT a 30A breaker, so it's possible to pull upwards of 50 amps thru EACH of these 30A legs if your boat isn't wired correctly with 30A breakers for each.

Moreover, as we've seen in the past and from MaineSail's recent long and excellent post, 30A connectors cannot really carry 30A continuous. They are actually 20A connectors which the industry pushed to have rated at "30A intermittent".

So, be very careful not to try to pull more than about 20-22A continuous thru these connectors. A pure resistive continuous load of only 25A -- such as two 1,500 watt electric heaters -- could easily cause these connectors to burn. You see them frequently in virtually any marina you visit.

Bill
 

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I used to have a Carver 3807 that had 2 - 30amp power connections. We either plugged into 2 - 30amp shore connections or 1 - 50amp - 220v with a splitter.
The 30 amp connections we had must have been continous, not intermittent because we pulled a lot of power on a continous basis.
1 connection had all 3 AC units on it and everything else on the boat was on the other connection. When all 3 AC units were running, which they were most of the time, they pulled about 29 amps.
 

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I used to have a Carver 3807 that had 2 - 30amp power connections. We either plugged into 2 - 30amp shore connections or 1 - 50amp - 220v with a splitter.
The 30 amp connections we had must have been continous, not intermittent because we pulled a lot of power on a continous basis.
1 connection had all 3 AC units on it and everything else on the boat was on the other connection. When all 3 AC units were running, which they were most of the time, they pulled about 29 amps.
Mine is set up where one AC unit runs on one 30 amp, and one runs on the other 30 amp. Nice if you do end up in a buggy or really hot marina with only one 30amp outlet, since one AC just cools the two aft cabins and you can shut the doors and the main unit easily cools everything else by itself. It is nice to know what is on what circuit (for instance, my water heater is on the same circuit as the smaller aft AC so you don't have hot water if you only hook up 30 amps to run the big AC).

I know I probably shouldn't have, but I ran the AC on my 32 footer one night in Indiantown at a dock where all there was, was a household outlet, and a connector to allow me to hook my 30 amp to it. It ran fine even though I didn't really expect it to.
 

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As mentioned you need a panel for each shore power inlet. Some times this is done on two panels some times it's done by using two columns of a single panel (and wiring it as two separate panels) Normal operation would have the power for each panel coming from each 30 amp inlet. As mentioned you could run a splitter to feed each circuit from a 50 amp outlet. You can also run a transfer switch which would than allow both circuits to run on a single 30 amp shore power (of course you need to be aware that you may draw over 30 amps causing the shorepower main to trip)

This is a common setup on Leopard/Moorings cats as an example.
 
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