Reply
 
Thread Tools Search this Thread Display Modes
 
Old 11-26-2017, 09:46 PM   #1
Guru
 
City: San Francisco
Country: USA
Vessel Name: Speedy Charlotte
Vessel Model: Beneteau Swift Trawler 44
Join Date: Oct 2016
Posts: 677
Question about reverse Y adapter (50amp to 2 x 30amp)

I know that with the reverse Y, you need to find two 30amp connections that are out of phase. Couple of questions regarding this:

1. How often are the two 30amp connectors on the same shore power pedestals out of phase?

2. When not out of phase, and you need to find another connection, do you carry a length of 30amp cord to run from the adapter to the other pedestal?

Thanks!
Mike

P.S. For what it's worth, the last time I got a 50amp hookup (in Monterey and Half Moon Bay), it was the old type and I wasn't able to connect! The guy at Monterey said he had an adapter to convert the old 50amp to the newer 125/250 connector, but someone was using it. I still haven't found any such adapter.
__________________
Advertisement

MichaelB1969 is offline   Reply With Quote
Old 11-27-2017, 01:32 AM   #2
Member
 
City: red bank
Country: United States
Vessel Name: loungeitude
Vessel Model: Sealine T47
Join Date: Jan 2017
Posts: 12
Yes you would have to run one leg to another pedestal that was a different phase. Sometimes they are all wired incorrectly and you are stuck running your gen for several hours at a time.
__________________

loungeitude is offline   Reply With Quote
Old 11-27-2017, 04:30 AM   #3
TF Site Team
 
Bay Pelican's Avatar
 
City: Chicago, IL
Country: USA
Vessel Name: Bay Pelican
Vessel Model: Krogen 42
Join Date: Oct 2007
Posts: 2,994
If you are planning on using a smart Y at other than your home slip buy the additional 30 amp 50 ft cord initially. You will need it at a good percentage of marinas.
__________________
Marty
Bay Pelican is offline   Reply With Quote
Old 11-27-2017, 05:39 AM   #4
Veteran Member
 
Flatswing's Avatar
 
City: Windmill Harbour, Hilton Head Island, SC
Country: United States
Vessel Name: River Girl
Vessel Model: 2004 DeFever 49 RPH
Join Date: Sep 2016
Posts: 96
'Personal experience is that most marinas with quality pedestals have both legs on the 30A connections to deliver 240v with the smart Y. The practical problem is that often adjacent boats may be already plugged into them! The 30Ax50ft cord helps alleviate this. Remember, if you use a smart Y, you boat will still only get 30A (not 50A) so may need to dial back high demand appliances accordingly.
__________________
Jeremy
Flatswing is offline   Reply With Quote
Old 11-27-2017, 06:48 AM   #5
Guru
 
psneeld's Avatar
 
City: AICW
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 20,033
Quote:
Originally Posted by Flatswing View Post
'Personal experience is that most marinas with quality pedestals have both legs on the 30A connections to deliver 240v with the smart Y. The practical problem is that often adjacent boats may be already plugged into them! The 30Ax50ft cord helps alleviate this. Remember, if you use a smart Y, you boat will still only get 30A (not 50A) so may need to dial back high demand appliances accordingly.
Not sure about this......

I think in some cases if not most, each 30 will provide 30 amps to each leg/bus of the 50A boat panel. So it will matter if you are set up with 240V appliances I guess.

On my boat, no 240V breakers so I get 30 amps on two separate busses.
psneeld is offline   Reply With Quote
Old 11-27-2017, 06:57 AM   #6
Guru
 
caltexflanc's Avatar
 
City: North Carolina for now
Country: USA
Vessel Name: Small Incentive
Vessel Model: Boston Whaler 130 Sport
Join Date: Aug 2011
Posts: 5,238
I found the issue typically comes up at funkier marinas that do not provide 50/240 service, or only have it on one dock. First discovered that at Rio Vista as a matter of fact.

Quote:
I think in some cases if not most, each 30 will provide 30 amps to each leg/bus of the 50A boat panel. So it will matter if you are set up with 240V appliances I guess.
No guessing needed. Yes you get 2 30/120 legs instead of two 50/120 legs off a 50/240 feed, and 30/240 for your 240v circuits.
__________________
George

"There's the Right Way, the Wrong Way, and what some guy says he's gotten away with"
caltexflanc is offline   Reply With Quote
Old 11-27-2017, 09:56 AM   #7
TJM
Senior Member
 
City: Essex, Ct.
Country: USA
Vessel Name: Harmony
Vessel Model: 1982 41' President
Join Date: May 2013
Posts: 177
Electrical for Dummy's question.
I am a pretty hands on guy and always understood the 30 amp x 120 VAC system. Am I correct in hearing that the voltage coming off of the 50 amp pedestal plug is 240 VAC ?
I have a Y splitter that plugs into the 50 amp outlet and then splits into 2 x 30 amp plugs. These two 30 amp feeds (with cords connected) go to each one of my inlets on the boat.
Where does the voltage get dropped down to 120 VAC / in the Y splitter ??
__________________
Tom and Cheryl
"Harmony"
1982 41' President
TJM is offline   Reply With Quote
Old 11-27-2017, 10:12 AM   #8
Guru
 
DHeckrotte's Avatar
 
City: Philadelphia, PA
Country: USA
Vessel Name: Revel
Vessel Model: 1984 Fu Hwa 39
Join Date: Nov 2015
Posts: 999
Easy enough to check. Measure the voltage between the two 'hots' at the pedestal. I'd expect that each pedestal's 30 amp receptacle is protected by a separate breaker at the dock's panel. With any kind of luck (and appropriate skill of the dock's electrician), the adjacent pedestal's receptacles are on opposite legs.
DHeckrotte is offline   Reply With Quote
Old 11-27-2017, 10:36 PM   #9
Guru
 
Maerin's Avatar
 
City: East Coast
Country: USA
Vessel Name: M/V Maerin
Vessel Model: Solo 4303
Join Date: Jun 2013
Posts: 825
Quote:
Originally Posted by TJM View Post
Electrical for Dummy's question.
I am a pretty hands on guy and always understood the 30 amp x 120 VAC system. Am I correct in hearing that the voltage coming off of the 50 amp pedestal plug is 240 VAC ?
I have a Y splitter that plugs into the 50 amp outlet and then splits into 2 x 30 amp plugs. These two 30 amp feeds (with cords connected) go to each one of my inlets on the boat.
Where does the voltage get dropped down to 120 VAC / in the Y splitter ??
The voltage doesn't get dropped. 240V is derived from 2 legs of 120V. The 50A receptacle on the pedestal has 2 120V hot legs and a neutral. The voltage between the 2 hot legs is 240V, the voltage between either of the hot legs and the neutral is 120V. So the voltage doesn't actually change.
Keep in mind that when you plug your 30A cordset into a 50-30 splitter, you're plugging into a 50A source, so the potential for overloading the 30A cordset exists. You're really safer if you can plug the 30A into the appropriate receptacle.
__________________
Steve Sipe
Selene 4303 Maerin
http://maerin.net
Maerin is offline   Reply With Quote
Old 11-28-2017, 05:55 AM   #10
Guru
 
psneeld's Avatar
 
City: AICW
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 20,033
Yes and no......yes, only if the cord shorts and no because the main breakers on the boat panel should be 30 amp.
psneeld is offline   Reply With Quote
Old 11-28-2017, 11:58 AM   #11
Guru
 
caltexflanc's Avatar
 
City: North Carolina for now
Country: USA
Vessel Name: Small Incentive
Vessel Model: Boston Whaler 130 Sport
Join Date: Aug 2011
Posts: 5,238
Quote:
no because the main breakers on the boat panel should be 30 amp.
Doesn't help your shore power cord, or anything else between dock and boat panel.
__________________
George

"There's the Right Way, the Wrong Way, and what some guy says he's gotten away with"
caltexflanc is offline   Reply With Quote
Old 11-28-2017, 12:52 PM   #12
Guru
 
psneeld's Avatar
 
City: AICW
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 20,033
And you are more likely to get hit by lightning from all the power cord failures I have heard of.

Burning up plugs is from resistance that may not trip any breaker on any set up.

If y cords were dangerous, lots of people would be letting us know, from the govt to the insurance companies.
__________________

psneeld is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 05:14 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012
×