Click for Walker Click for Alexseal Click for ZF Click for Abeking Click for Cheoy Lee

Shorepower issues

Discussion in 'Neptunus Yacht' started by Worthyvess, Aug 13, 2019.

You need to be registered and signed in to view this content.
  1. Worthyvess

    Worthyvess Member

    Joined:
    Sep 29, 2012
    Messages:
    66
    Location:
    South shore long island and fort lauderdale
    Just purchased a 2008 62' Neptunus with 2 50 amp cords, (these cords seem thin to me for 50 amp). Manual says I should be able to run a light load off of one 50 amp cord and that the other 50 amp is for additional ac. I can run everything except the ac on the one 50 amp cord, if I try to run just one zone of ac, with nothing else on, it trips the breaker in the engine room. I have had trouble with shore power at half of the marinas I have been to, trying to get the 2 50 amp cords to work. The genset runs the entire boat fine. I have a feeling someone changed the configuration from the factory.
  2. Pascal

    Pascal Senior Member

    Joined:
    Feb 29, 2008
    Messages:
    4,580
    Location:
    Miami, FL
    That’s pretty normal. Once you get to 55/60 feet a single 50 amp cord isn’t enough to run the whole boat especially in summer.

    I have a single 50amp on my personal boat (53 Hatteras) and with the full AC I have to turn off the water heater when cooking. On the 84 Lazzara I run (100 amp) we can’t run full AC plus cooking and a dryer or watermaker. Witha full house in summer when cooking I usually have to run one generator to supplement the 100 amp shore power.

    Look at your amp meters and see what you using. Hopefully Neptune’s didn’t hide them behind solid cabinetry or in the ER like so many builders do
  3. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    11,343
    Location:
    Fort Lauderdale
    I'm very familiar with the Neptunus' and they are a chiller boat with 2 chillers. I would start by having the chillers cleaned (acid washed). When they are dirty they tend to use a lot more AMP's to run because they're running higher pressures. This is probably a good majority of your issues. During the winter shutting off 1 chiller and only running 1 chiller is enough to keep up with the heat load, but not in the summer. The other issue is it is possible you have a bad connection on one end of your shorepower cords (either someone replaced the end and didn't get the wire connections tight tight) or I've also seen over time the boat side connection loosen up with the heating and cooling of the wires. How many amps are you drawing when you are having issues. A 50 amp cord is designed to supply 50 amps. It is easily exceeded on a 62' yacht if all a/c's are going, water heater is heating, and you're cooking. The Neptunus' I've run have had Charles transformers and they'd buffer the loads a little bit when compressors started up. Also what is your voltage? If it's closer to 250 volts you'll use less amps and most likely get away with 1 cord......if it's closer to 210 you'll use a lot more amps, especially on compressor start up and 1 cord won't be enough.
  4. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    11,343
    Location:
    Fort Lauderdale
    On one 55' Neptunus I managed, we had to have the terminal block changed on the main terminal strip where the shorepower came into. It was midship in the port side of the boat behind a panel in the small third stateroom, but this was on a 55' Express but the boat was only 5-6 years old at the time. At this point I would recommend getting a marine electrician out.
  5. Worthy vessel

    Worthy vessel New Member

    Joined:
    Feb 16, 2019
    Messages:
    32
    Location:
    Sarasota
    Thanks so much for that great advise. Do you know any marine electricians in the Sarasota area?
  6. Pascal

    Pascal Senior Member

    Joined:
    Feb 29, 2008
    Messages:
    4,580
    Location:
    Miami, FL
    You need to check amperage and voltage as you put loads on.

    As capt J suggested Descaling the chillers May help, it didn’t in our case. I also have a new 100 amp cable and plug so that’s not the issue for us.

    You just can’t run a 62 footer in summer on 50 amp.
  7. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    11,343
    Location:
    Fort Lauderdale
    I just ran a new 66' with everything on, with 8 people staying on board in the exumas without tripping the breaker once on a single 50 amp. We had everything going, 7 air conditioners etc, every ice maker/refrigerator etc. But it wasn't a chiller boat and I've found they'll really tax a 50 amp with one chiller running and the other starts up.

    I would speak to your dockmaster and see if they know of a good marine electrician in your area.
  8. Pascal

    Pascal Senior Member

    Joined:
    Feb 29, 2008
    Messages:
    4,580
    Location:
    Miami, FL
    That a pretty impressive. Many chillers use VFDs and ramp up gradually with no surges whatsoever.

    Battery chargers use quite a few amps too...
  9. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    11,343
    Location:
    Fort Lauderdale
    If the Neptunus chillers are original they usually used 2-2.5 ton Marine air chillers with no VFD's.
  10. Worthy vessel

    Worthy vessel New Member

    Joined:
    Feb 16, 2019
    Messages:
    32
    Location:
    Sarasota
    The boat has 3 chillers that are fairly new.
    The problem is that the manual says I should be able to run some AC off the main shore power cable, but when I try to run just one chiller and one zone of AC, even with other large draws off such as hot water and stove the breaker in the engine room pops. And I am drawing very little amps when it breaks.
  11. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    11,343
    Location:
    Fort Lauderdale
    It could be a bad breaker or bad connection on the shorepower cord. How many amps are you drawing when it pops? If it's way under 50 amps, You should easily be able to run all zones of AC as the fan coils use very little amperage and 1 chiller on a 50 amp.
  12. Worthy vessel

    Worthy vessel New Member

    Joined:
    Feb 16, 2019
    Messages:
    32
    Location:
    Sarasota
    It pops at under 15 amps. works fine with genset. However I can run everything else on the line (stove, hot water, refrig, etc and get up to over 20 amps and it does not pop.
    Could it be the wiring of the new chillers?
  13. Capt J

    Capt J Senior Member

    Joined:
    Jul 11, 2005
    Messages:
    11,343
    Location:
    Fort Lauderdale
    If the same breaker does not pop while on genset, then the breaker is most likely good. Again, look at your shorepower cord and it's connections. It really screams to me a bad shorepower cord end or connection at the cord end, could also be where the cord attaches inside the boat. It could be the wiring at the chillers too.
  14. Pascal

    Pascal Senior Member

    Joined:
    Feb 29, 2008
    Messages:
    4,580
    Location:
    Miami, FL
    Too many unknowns.

    What voltage do you have at the panel?
    Are the chillers 120v or 240v? How many BTUs?
    You said they are new. Are they the same as the original? Did the old ones cause the same issue?
    Have you tried running a different chiller?

    If you can run higher loads overall combining water heaters, chargers, appliances etc then I would eliminate a shore power issue. Check to see if the cord or plugs gets hot under load
  15. bayoubud

    bayoubud Senior Member

    Joined:
    Feb 19, 2017
    Messages:
    483
    Location:
    Florida
    We run our 72' ph on one 50 amp cord at our dock with two 4 ton chillers, galley frig, battery charges, plus other small amp equipment. Draws about 48 amps with both chillers running, 25 amps on one chiller with all high amp equipment off. We do use both cords while staying on the boat. Also have a small panel with a transfer switch next to the ER main panel to designate one cord or two cords that must be set. Not sure about your setup, but if you have the same it has to be set to the number of cords being used. Otherwise, you need an electrician to troubleshoot as suggested.
  16. rtrafford

    rtrafford Member

    Joined:
    Jul 13, 2019
    Messages:
    191
    Location:
    Ft Lauderdale
    If the chiller runs fine under genny, but breaker fails under shore power....well, you're mind has nowhere to go but to suspect low voltage resulting in larger amp draw through that breaker to get the system to run. Break out the meter and check the power both with no load and then under load. If there's a big drop-off under load, look more closely at that cord. Swap cords and check again.
  17. Capt Ralph

    Capt Ralph Senior Member

    Joined:
    Sep 8, 2004
    Messages:
    7,388
    Location:
    Satsuma, FL
    Let me get on the same page,, Is this the shore service breaker that trips and when on gen-sets, this breaker is not used?
  18. rtrafford

    rtrafford Member

    Joined:
    Jul 13, 2019
    Messages:
    191
    Location:
    Ft Lauderdale
    Reads as it's his chiller breaker that is fine under genny but trips on shore power.
  19. Worthy vessel

    Worthy vessel New Member

    Joined:
    Feb 16, 2019
    Messages:
    32
    Location:
    Sarasota
    I am finally back on my boat (2008 62' Neptunus) bought in Ft Laud this summer and moved to Sarasota(with Capt Andrew). Capt J knows the boat- blue hull- Alta Vida.
    I don't think it is wired as a typical 62. The 2 shore power cords are thinner than typical 50 amp cords. They are only 3 wire instead of 4. The boat has 3 chillers. On the electrical panel the 24 volt charger is under the 120v side and the 12 volt charger is on the 240v side. This seems strange to me.
    The manual says I should be able to run the boat on one 50 amp cord- however I am not able to. Seems like one cord is for house and one for AC.
    I am also not able to extend the length of the shore power cord with a standard 4 wire 50 amp power cord.
    Can anyone explain this setup to me- can I extend the cords and can I run on one 50 amp cord
    Thanks so much.
  20. Pascal

    Pascal Senior Member

    Joined:
    Feb 29, 2008
    Messages:
    4,580
    Location:
    Miami, FL
    3 wire shore power cords (two hot plus ground, no ground) are used with isolation transformers.

Share This Page