Fuse size question

Discussion in 'Boat Electronics' started by Bigpondonly, Apr 8, 2009.

  1. Bigpondonly

    Bigpondonly Bloodydecks Seafood Co.

    Location:
    San Diego
    Name:
    Dave
    Boat:
    Parker 2120
    • Messages:
      (1,484)
    • Likes Received:
      (258)
    I'm installing an amp on the boat. Max draw is 28amp. Running 10' of #10ga. to provide power. What size fuse/breaker do I need to run inline to protect?
    Thanks
    Dave
     
  2. No Bad Days

    No Bad Days Capt. 50 GRT

    Location:
    Huntington Beach
    Name:
    Scott
    Boat:
    38' Californian
    • Messages:
      (62)
    • Likes Received:
      (0)
  3. MM2

    MM2 thunnus

    Location:
    murrieta
    Name:
    charlie
    Boat:
    26'PACEMAKER SPORTFISHER "CORAZON"
    • Messages:
      (332)
    • Likes Received:
      (0)
    #10 wire is good fo 40 amps, make sure to use marine grade wire an the proper size lugs and but splices.Good Luck CJ/MM2
     
  4. Moleculo

    Moleculo -

    Location:
    Monrovia, CA
    Name:
    Tim
    Boat:
    None
    • Messages:
      (1,128)
    • Likes Received:
      (5)
    If the max current draw of the Amp is 28amps, you should install a fuse that is just a little larger than that. Around 35 amps will be fine. 40 amps is too large. The idea is to blow the fuse in the event that the device (amplifier in this case) shorts and starts to draw more current than it's supposed to. If there's not a fuse that blows, it keeps drawing more and more until the cable fails, and shorts itself out, which leads to an electrical fire. Not to sound too alarmist, but I know people that this has happened to in their car, while driving down the freeway.

    Don't base the fuse size on the wire guage size, base it on the device current consumption. Base the wire guage size on the distance you're running along with the current consumption.
     
  5. Wideflange

    Wideflange Newbie

    Location:
    NorCal
    Name:
    Greg
    Boat:
    '20 Mako CC
    • Messages:
      (218)
    • Likes Received:
      (0)

    X2.....Always err on the safe side. 40 amp draw on a #10 depends on length as well. Voltage drop equals HEAT. Resisitance is real. As with all terminal ends. Use only closed end lugs with adhesive, heat shrink wrapped seals and marine grade wire. It will last a long time if done correctly.

    If I had a 28amp intended draw, I would set a 25amp fuse inline.
     
  6. easydoesit86

    easydoesit86 nubbie

    Location:
    lacey wa usa
    Name:
    maarten
    Boat:
    22' 672 Campion "Skidder"
    • Messages:
      (1,688)
    • Likes Received:
      (215)
    If in doubt , start small and work your way up, start with a 20 and if it blows, just put the next size in.
     
  7. Dirtguy

    Dirtguy "It's all Good!"

    Location:
    Gilbert, AZ
    Name:
    Carl
    Boat:
    26' Sea Ray, "yes dear..."
    • Messages:
      (1,179)
    • Likes Received:
      (5)
    Location of the fuse is also important. Closer to the battery the better.

    dg
     

Share This Page