Advice needed from the electrical gurus

Discussion in 'Power cuts' started by Two Oceans Aquatic S&S, 22 Jun 2011.

  1. Two Oceans Aquatic S&S

    Two Oceans Aquatic S&S

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    Guys I hope someone can calculate this for me. If I have a 220V pump which uses 55W how long could I run this pump for If I used a standard car 12V battery and a inverter ?

    Thanks
    Trev
     
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  3. ThaneF

    ThaneF

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    Hi Trev,

    I'm no expert on this but I have bought my self and inverter and battery. First off, you MUST get a pure sine inverter. If you don't the pump will "gig" I guess. Secondly, a standard car battery doesn't have many amp hours - you are looking for a deep cycle 100+AH battery.
    I know this doesn't really answer your question but that is the advice I have to give
     
  4. Two Oceans Aquatic S&S

    Two Oceans Aquatic S&S Thread Starter

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    thanks you have given great advice thanks
     
    Last edited: 22 Jun 2011
  5. danimal

    danimal

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    it depends on the amp hours of the battery - if a standard car battery has 75A-hrs, it can output 75Amp for 1 hour, or 900Watts for 1 hour (75A @ 12V = 900W).

    so if you have 900W-hrs, and you are using 55W then it should last 900/55 = 16.4hrs.

    this is assuming 100% efficiency in the converter which you won't get, 90% if it's a good one. so around 14-15hrs.

    and as ThaneF said, it must be a pure sine inverter. pseudo-sine is the wrong shape waveform and will make your pump kuk itself :p
     
  6. Two Oceans Aquatic S&S

    Two Oceans Aquatic S&S Thread Starter

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    OK great that is perfect as I am only looking for about 6 hours max anyways.

    Thanks guys, where is the best place to get the correct inverter and what do they cost ?

    Trev
     
  7. mariusmeyer

    mariusmeyer

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    Dont use a car battery. You will use it once and kill it. They are not supposed to be drained like deep cycle batteries.
     
  8. rakabos

    rakabos

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    My modified sine wave inverter cost R3000 with two deep cycle 102ah batteries and ive never had a worry since. Runs the return pump and heater for over 12 hours
     
  9. Two Oceans Aquatic S&S

    Two Oceans Aquatic S&S Thread Starter

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    But what if I am not draining it I will need to pump only 500Ltr at a time between charges which should take about 1 hour with a 2500Ltr/hr pump

    Trev
     
  10. Two Oceans Aquatic S&S

    Two Oceans Aquatic S&S Thread Starter

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    Cost of the inverter alone ?
     
  11. Irma

    Irma

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    I was doing some research into getting an inverter and was dismayed at the price of the pure sine wave inverters. I then asked my brother's advice, seeing as he was an Eskom electrician and his comment was the following: -

    "Do you really think that Eskom is supplying a pure sine wave in there electricity? It's actually more in between the two patterns. Not quite round but more boxy with rounded corners"

    I have no idea what this means and if it's true or not but it makes you think!
     
  12. coswecanfly

    coswecanfly

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    Trev - if you're not planning on running anything that has variable speed setting, just get an old, second-hand oil welder... It's only about R500 and will work just as good... ;)
     
  13. Two Oceans Aquatic S&S

    Two Oceans Aquatic S&S Thread Starter

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    Now you lost me totally.........................help
     
  14. butcherman

    butcherman Moderator MASA Contributor

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    trev call geogre and aqua africa he can sort you out with a great pump that runs straight off 12v ;)
    or just get yourself a 12v bilge pump from a boat shop
     
  15. rakabos

    rakabos

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    lol +1
     
  16. coswecanfly

    coswecanfly

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    PM me your number and I'll call you and explain... :)
     
  17. coswecanfly

    coswecanfly

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    Or listen to Butcherman... Probably cheapest and easiest... :biggrin:
     
  18. Two Oceans Aquatic S&S

    Two Oceans Aquatic S&S Thread Starter

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    I have a few bilge pumps but they dont come close to 500Ltr/hr at over 10m length and about 3m height
     
  19. coswecanfly

    coswecanfly

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    For the rest:

    An oil welder is just a inverter i.e. turns 220v and few amps into PLENTY...
    Put the "out" cable on the correct terminal (can't remeber which one now) and it turns 12v into 220... Voila... :biggrin:

    Just does not work with things that have variable speed settings like blenders (ask me, I've tried... :eek:)
     
  20. butcherman

    butcherman Moderator MASA Contributor

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  21. KeeganP

    KeeganP

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    Yeeeessssterday..... You really gota be a guru to understand whats going on here...:whistling:
     
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