Inverter leads

Discussion in 'Motorhome Chat' started by PJGWiltshire, Mar 14, 2015.

  1. PJGWiltshire

    PJGWiltshire Funster

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    About to install a 1500W inverter. All going well until I have been forced to secure it about 1.25 m from batteries. The leads that came with the inverter are now to short. Some advice from you experts would be most grateful . Am I correct in working out that I now need to run the cable in a thicker grade as the distance from the batteries has now increased. If that is the case would 8mm thick be ample
     
  2. jonandshell

    jonandshell Funster

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    No it wouldn't!

    Your inverter is rated at 1500 watts, that would normally be a constant rating. You should assume double that for peak current.
    An inverter is also rarely more than 90% efficient, that means you should add 10%. Therefore you should calculate peak current for 3300 watts.

    At 11 volts, the voltage your batteries will be at under heavy load, the DC current could be as high as 300 amps!
    This is a worse case, but 35mm cable would be a safe bet, given the length required.
    I reckon you would be OK with 25mm though.
     
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  3. Zains Pops

    Zains Pops Funster

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  4. Techno

    Techno Funster Life Member

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    I expect the OP means 8mm diameter which is not a recognised way of sizing cable in relation to current carrying capacity. John is referring to 25mm cross sectional area of the copper conductor.(y)
     
  5. PJGWiltshire

    PJGWiltshire Funster

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    Thanks for your help, have also tracked down an old post where Andy states 35mm, so I will go with that. I have worked out the fuse as 125A (1500/12v) would this be be suitable or should I get a 300A mentioned by John
     
  6. Techno

    Techno Funster Life Member

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  7. SUGGY

    SUGGY Funster Life Member

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    My inverter is 3kw peak 2.5kw constant running ,
    i conected it up using 100 amp unipren cable .
    When using the Remoska it takes around 50 amp from the batteries ,
     
  8. PJGWiltshire

    PJGWiltshire Funster

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    Many thanks Andy and everyone else. Shall get on and order.
     
  9. rapido convert

    rapido convert

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    Hi, i use heavy duty jump leads to connect my batteries and inverter, it is much cheaper to buy a set off fleabay then cut the clamps off, the last set i purchased were 30mm copper and 2.8 meters long they cost £14·00 delivered, ps my inverter is 2000w /4000w peak power pure sinwave and is 1.5 meters away from the lead battery in my battery bank.
    This set up has served me well without over heating /power loss for many years i have a 1kw solar system and only camp without hook up.
    Cheers
    Andy.
     
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  10. Techno

    Techno Funster Life Member

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    I use the Blue sea brand fuse holder, very substantial quality kit.
    [​IMG]
     
  11. Techno

    Techno Funster Life Member

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    [​IMG]
     
  12. Techno

    Techno Funster Life Member

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    [​IMG]
     
  13. PJGWiltshire

    PJGWiltshire Funster

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    what is the switch over junction for
     
  14. Techno

    Techno Funster Life Member

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    300amp isolator
     
  15. PJGWiltshire

    PJGWiltshire Funster

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    Everything ordered, should be here midweek. Looks simple enough to clip together and the photograph guide is a dream. Is that four(4) batteries I can see and are they the cables for the solar panel
     
  16. Techno

    Techno Funster Life Member

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    yes
     
  17. PJGWiltshire

    PJGWiltshire Funster

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    looks very tidy
     
  18. Steve

    Steve Funster Life Member

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    25mm ok but 35mm better.
     
  19. PJGWiltshire

    PJGWiltshire Funster

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    Looks like I have made an error when buying the inverter. Checking it again I now note that it is a duel supply type. Not sure why this is so. Is it a case of running a positive and negative to both terminals from the battery or can I go through a junction box for both + and -, with one single feed to the battery via a 200A on the + (Intend using 25mm2 (230A) cable and Isolator.
     
  20. Techno

    Techno Funster Life Member

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    Picture?
     
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