help on wiring 240v switch to 12v wire.

Discussion in 'Tech/Mech General' started by Welsh girl, Apr 10, 2015.

  1. Welsh girl

    Welsh girl Funster Life Member

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    We have bought an inline switch, for a household supply but was informed that we could use it to put in after an inline fuse from the leisure battery so that we can just switch off the inverter wired to the battery instead of removing the fuse every night.
    Every time the fuse is inserted it sparks and I'm a little worried that the battery will blow up as it is only around 12 inches away from the battery that is housed under the bed.
    The battery is normally used for the orthopedic electric beds( already fitted in van) but is used to power other things via an inverter as the electric function is hardly used for the beds.
     
  2. pappajohn

    pappajohn Funster Life Member

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    You could put it in the inverter feed wire but it would last milliseconds.

    230vac switches are generally rated at 10amps or less.

    ...your inverter could be needing 10 times or more than that amount of amps.

    To do it properly you need a heavy duty relay capable of 200 to 300 amps and a switch to control the relay.

    If the inverter is that close to the battery DONT keep removing and inserting the fuse.....the battery may be gassing and could ignite with a very big bang.
    Turn off the inverter at its own switch.
     
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  3. Lenny HB

    Lenny HB Funster

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    Yep & only about 2 amps switching DC.
     
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  4. pappajohn

    pappajohn Funster Life Member

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    How big is the inverter.?
     
  5. Welsh girl

    Welsh girl Funster Life Member

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    The inverter is 300 watts. Pure sine wave.
    The switch is rated at 6a, 250v.double pole.
     

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  6. JeanLuc

    JeanLuc Funster

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  7. Welsh girl

    Welsh girl Funster Life Member

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    We need to remove the inverter to use on the front leisure batteries that are charged via the solar panel and the engine when driving.
     
  8. Reallyretired

    Reallyretired Funster

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    Just use a 40amp automotive relay and any old switch to operate the relay. That's what i use on my little 500w inverter that just runs the washing machine.

    Edit, before anyone mentions it I do realise a 500w inverter can draw more than 40amp, but this is for a specific purpose and never draws more than 25a.
     
  9. pappajohn

    pappajohn Funster Life Member

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    Nope...300 watts at its full potential will draw 25 amps.

    25amps through a 6amp switch is asking for a fire.

    75 watts will be the switches absolute limit
     
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  10. Welsh girl

    Welsh girl Funster Life Member

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    Thanks for the replies. I'll get another switch or an isolator.
    Definitely glad I asked.
    Thanks again guys.
    Saved our bacon, literally! !!
     
  11. Lenny HB

    Lenny HB Funster

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    No it's not that is the AC rating the DC rating will be about 1 amp.
     
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