I haven't priced the connectors but I'm pretty sure you cant buy them all for less than $30... they'll probably be closer to $30+ a piece. The other issue is where to make the splice. The store bought ones are typically molded into the cables... very nice! You would have to either tape the junction up or try to get two cables into one connector... very difficult.

 

50 to twin 30's....No reason you couldn't. Waterproofing would be the weak link in the chain.

A 30 to twin 30's makes no sense to me. I've seen them, but still scratch my head! I'm thinking you would only be carrying 15 amps per side at the split. If so, that's some serious power management.

 

I have a 50 amp and a single 30 amp at the dock. I could run the 50 to two 30 amps and cover most everything. For the 30 to twin 30 amp adapter, it would be to run a few items on each side of the panel but nothing greater than 30 amps combined.

I have come across the 30amp twist connectors for around $10 a piece on eBay and Amazon. For the price it seems as though I could save around $300 on both connectors this way.

 

I would watch this one:
http://www.ebay.com/itm/Marinco-153...31487?pt=Motors_RV_Trailer_Camper_Parts_Accessories&hash=item19ea0d6f9f&vxp=mtr

 

I've done it. Bought the blank Y on ebay. Hubbell connectors and waterproof boots are less expensive than Marinco. I think it cost me total around $110. Check on Amazon.com. This was close to 10 years ago. Might be easier (but not cheaper) to buy a used one on ebay... but it's the thrill of the project.

 

A single 30 to duel 30s is important for me because my AC runs off of one plug and the rest of the boat off the other. If I only have one power outlet to choose from at the dock I don't want to have to switch cords to have hot water and have ac. The y adapter solves this problem.

 

If you have ISO-Boost transformers it will not work, they isolate the neutral, also keep in mind 50 amp cords are 120/240 so pay attention to what you're doing. IMHO your family's safety is not worth trying to save a few bucks over. From a liability standpoint I wouldn't go near it with a 10' pole.

 

Wait...are we talking about using a 50amp dockside and splitting it into two 30amps which plug into the boat? If yes, that's easy. If you are talking about twin 30s dockside plugging into a boat that requires a single 50amp plug, that's tricky. That's nut just connecting wires. There are some sort of electronics in those adapters.

 

If I'm reading it correctly, he has the same setup I have at my new to me marina. One receptical is a 125/250 V, 50 amp. The other is a straight 120V 30 amp.

The only downside is losing 5 amps on each side with the 50 amp splitter..... No biggie.

New they are $200. Used, as shown, ~%50.

By the time all is said and done, I'm thinking the cost would be a wash on building v. a good condition 50 to twin 30's.

 

"The only downside is losing 5 amps on each side with the 50 amp splitter..... No biggie".

To the contrary, if I am not mistaken you have 50 Amp per leg so keeping an eye on your amp draw is advisable.

 

"The only downside is losing 5 amps on each side with the 50 amp splitter..... No biggie".

To the contrary, if I am not mistaken you have 50 Amp per leg so keeping an eye on your amp draw is advisable.

Nice catch, you are exactly right.