Y-adapter

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MikeM

Senior Member
Joined
Jul 6, 2012
Messages
281
Location
USA
Vessel Name
Tuscan Sun
Vessel Make
Krogen 42
I've never been able to power my boat with the smart 30 to 50 y-adapter that came with her. I finally figured out that it didn't work. So now I need a new one.

Is the "smart" adapter worth the extra money. What does it do or not do for you?

Mike
 
Doesn't each 30 need to be on a separate leg for the Smart Y to worK? I have heard that this is hard to find because you need the two 30's close enough to plug in.

I own a Smart Y that came with the boat but have never used it.

Someone enlighten us. MikeM's Y might be fine.
 
The Y only works on a dock that has been wired to allow its use.

Many , even most will not.

THe check is with a voltmeter before plugging in.

Plan B could be an internal switch to seperate 1/2 the boat and (2) 30A power hoses, with a second 30A inlet.
 
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With most docks I've never had an issue getting a Smart Y to work.

The two 30a recepticals need to be out of phase for a true Smart Y to engage. On occasion you may need to use a extra 30a cord to plug one of the 30a legs on the Y into a 30a receptacle on a power post across or down the dock from the one at the power post closest to you in order to get two recepticals that are out of phase.

A volt meter will not tell you if the recepticals are in or out of phase.
 
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What is the downside of a "dumb" Y?
 
Dumb Ys are used with a 240 V, 50A shore power outlet to adapt to two 120V, 30A outlets. Smart Ys do the opposite, combine two shore power 120V 30A to one 240V 30 A (but really a 50A plug).

David
 
A volt meter will not tell you if the recepticals are in or out of phase.

A voltmeter will show voltage across two circuits that are out of phase and no voltage across two cicuits within phase.
 
I had a similar issue with the one that was on my boat when I purchased it. I tried it at a marina and it didn't work. I verified power in both 30 amp outlets, but still no go. I assumed it was smart Y. However, when I saw the cost of a new one I decided to try it at my home marina. Sure enough, it worked fine. I was told that each 30 amp has to be on a separate leg. Also found that one other thing the smart Y does is protect you from getting shocked if you have one leg plugged into live power and touch the prongs of the free side.
 
The smart wye has a relay that only energizes if there's 240V present. That's why it's "smart". I have a Charles, it also has an LED that lights when it's energized. And, yes, sometimes you'll need to hunt around to find a pair of outlets on separate legs. The easiest method is to just take the smart wye and use it to test, may need to use a 30A cord to get to the 2nd outlet.
 
Thanks for the info. However, I'm still not sure what happens if I try to use a "dumb" y. I understand it protects you from being shocked. Does it also provide some protection for the boat?
 
I carry a separate 30 amp power cord so that I can connect the second part of the smart Y to a post away from my slip. Found this is the only thing that works at some marinas. Note: This was 10 years ago when we were in the US.
 
on a 50 amp split phase 240 vac line, how many amps do you think you can draw from a single hot wire to neutral which yields 120vac.
And how many amps can you draw from hot to hot at 240 volts.

If you could draw 50 amps hot to neutral then you would have 100 amp service across hot to hot, but the service is only 50 amps total.
 
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