400 SB- 30amp-to 50amp

Just hook up a couple three of these jobies..

temp_wiring01.jpg
 
osd9 said:
........whenever you convert a 50A shore power down to 30A service to the boats inlet...regardless of wether the pedestal is 50A 125/250V or 50A 250V.....you will always have a 30A rated power cord/adapter in there somewhere and a 50A breaker at the pedestal protecting everything. ........
Click to expand...

I said the above earlier in this thread.....and it's still true....

I think everyone that travels and transients carries a various supply of splitters and adapters....it's the nature of the beast. I do and I use them. However, I would be very cautious if I had to use a splitter on a 7/24 basis....again...for all the reasons already stated above. IMHO, these splitters and adapters are to be used on a temporary and guarded basis.

Now, that said, I know of least one marina in NJ, and I'm sure that there are more, that only supply 50A 125/250V at the pedestal. As a transient there, I have no issues using my splitter....but the locals who need single or double 30A service to their boat are there permanent and need to be aware of the issues.
 
Post #40 by 1stSeaRay is a good (and correct) explanation of the way the splitter works.
If you have a 240 50 amp service you get 2 120 volt 50 amp legs.
IF you have 25 amp breakers instead of 50 you get 2 120 25 amp legs after splitting.
 
My home marina only has 240V/50A service in all 40'+ slips. So, my boat is always connected to shore power through the Marinco splitter. Power pedestal has a 50A breaker protecting the 50A outlet. However, my boat has 2x30A breakers located directly at the shore power inlet. I assume that these breakers protect all inside wiring between the power inlets and main AC panel. What are my risks in this case?
 
Westie said:
...IF you have 25 amp breakers instead of 50 you get 2 120 25 amp legs after splitting.
Click to expand...

If you have two 25 amp breakers then what you have are two 25 amp circuits....you never had a 50 amp service to start with....which is not what this discussion is all about..


Besides...is there even such a thing as a 25 amp receptacle????
 
aquadancer said:
My home marina only has 240V/50A service in all 40'+ slips. So, my boat is always connected to shore power through the Marinco splitter. Power pedestal has a 50A breaker protecting the 50A outlet. However, my boat has 2x30A breakers located directly at the shore power inlet. I assume that these breakers protect all inside wiring between the power inlets and main AC panel. What are my risks in this case?
Click to expand...


This is what this discussion is all about.....

I'll assume you have a pedestal with a 50A 125/250V receptacle and a splitter that breaks that out to two 30A 125V receptacles. The issue is, is that both 30A receptacles are protected to 50 amps. So the Y splitter, the two 30 amp cords and all the wiring upto and including the wiring at your power inlet just before the breaker, are all rated for only 30 amps....yet they could potentially be 'asked' to carry 50amps if a fault occurs between the pedestal and the boat's 30 amp breaker....fc3 talked about this earlier.
 
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This splitter should work.....wanna bring it to market???

50Asplitter.jpg
 
Dom - right, that is what the discussion is about.. except Frank W. pointed out that the risk was to the unprotected wiring from the boat shore power inlet to the main breaker panel. In my case (and yours), we have 2x30 breakers at the inlets. Does that limit our risk to damaged shore power cord (and whatever consequential damage)? However, boat wiring should be fully protected...
 
aquadancer said:
Dom - right, that is what the discussion is about.. except Frank W. pointed out that the risk was to the unprotected wiring from the boat shore power inlet to the main breaker panel. In my case (and yours), we have 2x30 breakers at the inlets. Does that limit our risk to damaged shore power cord (and whatever consequential damage)? However, boat wiring should be fully protected...
Click to expand...

It depends on what the fault is and where in the ciruit it occurs.....and if there is one fault or multiple faults. Many boats, my old 330DA for one, had two power inlets on the hull sides.....no breakers. The first, and only Circuit protection, was in the cabin in the main electrical closet. So in boats from that genra, the boat's internal wiring is affected also.

You can 'what if' this thing to death.....but the reality is, it 'could' happen.
 
Jeff/Dom

I believe Sea Ray incorporated the breakers you have on your shore power entrance after a number of fires/near fires from the problem I described. The 400/410DA's we had in NW Fla to exhibit this issue were made earlier than your 2002-3's.
 
Just so you know, 30A is plenty to start a fire, even on wire rated for it. In the case of a faulty connector (loose or corroded connections) heat will start to build at the connection. Depending on the load, the wire can get quite hot. As the heat builds, the voltage drops and the amperage goes up. This continues until the wire fails (something melts, or starts a fire). The picture below shows 30A 240V cord caps in various stages of failure. These were on 10 gauge wire with a 22A load. As these are used in temporary installations the cable gets banged around quite a bit, and as a result the terminals in the caps tend to get loose over time. These cables were connected to a distro with 30A breakers....despite the fact that at least one of these was smoldering when we found it, the breakers did not trip.



IMG_1906.jpg
 
I guess I won't be using my 15kw generator thats strapped to the platform anymore. It has 50 amp service and apparently, is unsafe for risk of fire. Damn. :smt089
 
osd9 said:
This splitter should work.....wanna bring it to market???

50Asplitter.jpg
Click to expand...

Dom has the right solution. The breaker at the source must be appropriate to the wiring that runs from the breaker to the load.. You can look up the values, but off the top of my head
14 ga wire - 15A
12 ga wire - 20A
10 ga wire - 30A
8 ga wire - 50A

If the wire is thinner than shown above, it's probably not spec. Also, those figures are for wires that are not bundled into a thick cable or run in a sealed conduit. You have to de-rate for that.

I sent an email to Marinco yesterday. Asked if it was safe to use a 50A to 30A adapter when there would be a 50A breaker protecting 30 feet of 10 gauge wire outside the boat and 20 feet of 10 gauge wire inside, which seemed to me to violation the National Electric Code of NFPA. So far, no response from them. Probably legal is sweating it right now. I do not expect to ever hear from them about this, but I'll try again tomorrow. Maybe they already have a Domadapter on the drawing boards right now.

Best regards,
Frank
 
I'm trying to understand that as well. Electrical isn't my strong suit...
Just because there's 50 amps available doesn't mean the boat can actually try to draw 50 amps through a cord only rated for 30- the main 30 amp breaker at the panel would trip.

Right?
 
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