Charging a Mobility Scooter off EHU

Discussion in 'Motorhomes for the Disabled' started by Bilbo Baggins, May 9, 2016.

  1. Bilbo Baggins

    Bilbo Baggins Funster

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    Sugestions please, as to how I could charge a 24v (2x12v) mobility scooter when no electric hook up is available.
    Does anyone use an inverter whilst on the move? Ta
     
  2. Robert Clark

    Robert Clark Funster Life Member

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    We charge our electric bike batteries off our inverter, but only when driving, so that the leisure batteries are not drained.
     
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  3. TheCaller

    TheCaller Funster

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    That's what we do with the electric wheelchair (also 24V). In an emergency, I have given it a partial charge while stationary, but as the wheelchair is 2 x 56AH & the M/H is only 2 x 95AH, a full charge isn't a good idea! (although 200W of solar helps on a sunny day).
     
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  4. hilldweller

    hilldweller Funster Life Member

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    Yes - a 300W sine wave inverter. Not a good idea to do it when not on the move unless you have massive leisure batteries.
     
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  5. Bilbo Baggins

    Bilbo Baggins Funster

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    Thanks for your replies. Thought that I would have to do it that way. I believe that the charger draws about 1.2 amps, so assume that would be about 288w, so a 300w inverter appears to be the one?
    Didn't realise it would be from the leisure battery though, could someone tell me why that is. TIA.
     
  6. hilldweller

    hilldweller Funster Life Member

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    Normally you wire an inverter to the leisure battery so that if you flatten it you still get to start your engine. Normally when the engine is running it charges the leisure battery. You may have heard "split charge relay", that's what does it.

    However with a plug in inverter you may plug it into the engine battery using the cigar sockets in the cab or to the leisure battery using the sockets in the rear. Cigar sockets are more like 200W so not up to much for inverters.
     
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  7. Bilbo Baggins

    Bilbo Baggins Funster

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    Thanks Hilldweller, I did think that the power draw might be too much for the 'cigar sockets'
    So if its connected to the leisure battery, yes it would not flatten the engine battery, but if we turned off the engine
    and went for coffee, we would need to disconnect it first, otherwise it would continue to draw from the leisure battery.
    However thats not a real problem if it meets our original aim of charging the scooter batteries.
    And you think that a 300w inverter would be sufficient. TIA.
     
  8. Lenny HB

    Lenny HB Funster

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    You need at least a 500 W inverter advisable to run inverters at a max of 80% of their capacity also a 300w would probably trip out with the surge when you connect the charger.
     
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  9. Snowbird

    Snowbird Funster Life Member

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    If you are only going to use an inverter for charging your mobility scooter batteries whilst driving I would suggest hot wiring your inverter into your engine battery. The wiring on many motorhomes that charge the leisure batteries from the alternator is not designed to charge the batteries when having a constant pull such as an inverter running for long periods. The wiring from the alternator to the engine battery is much heavier.
     
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  10. Bilbo Baggins

    Bilbo Baggins Funster

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    Thanks for that Lenny HB. I'm no electrician so gratefull for that advice.
     
  11. Bilbo Baggins

    Bilbo Baggins Funster

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    And thanks, Snowbird. Something else I will consider befor putting this plan into action.
     
  12. TheCaller

    TheCaller Funster

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    If you are only going to use the inverter to charge the scooter & if you are only ever going to use it while on the move, then you could wire it to the starter battery. Otherwise, as Brian says, you are in danger of flattening the battery & not being able to start the engine. If you do connect it to the starter battery, it's even more important that you turn it off if you stop & go for a coffee.

    Another consideration is where you are going to mount the inverter. It should be as close to the battery as reasonably possible. It doesn't matter how long the cable from the inverter to the charger is - the voltage drop at 230v & 1.2A will be insignificant, but the current between the battery & the inverter will be 25 - 30A. Then you have to consider how easy it is to get to the inverter to switch it on & off - unless you get one with a remote.

    Snowbird makes a good point - not all motorhome leisure battery charging & wiring systems are created equal - some appear to use wet string. What is the make & model? Someone on here will know whether the charging system is up to replacing what the inverter draws.

    I agree with Lenny - you probably need a 500W inverter. I use a 600W pure sine wave inverter wired to my leisure batteries, but then I use it for other things & when stationary.
     
  13. TheBig1

    TheBig1 Funster Life Member

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    the other option is get an electrician to do what I did on a previous van.'

    run a separate 100amp split charge relay to an anderson plug and make up a wiring harness that you charge the batteries direct from the alternator. you would need to lift the battery cover and pull the battery connector plugs out and plug into the connectors on the harness.
    most 240v mains chargers are 4amp output so you need many hours to recharge. An 8amp charger will recharge twice as fast and if you search ebay or go to your local mobility shop they are easy to obtain but not cheap
     
  14. Snowbird

    Snowbird Funster Life Member

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    There is of course this option, which is much easier than messing about with inverters.
     
  15. Snowbird

    Snowbird Funster Life Member

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    Or if you want a foolproof one that switches off when the engine is not running and gives a more powerful charge, at a cost.
     
  16. SUGGY

    SUGGY Funster Life Member

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    Send a PM or conversation to G8SYN , he used to run a generator to supply power for his wife's scooter and her rechargable breathing unit but sorted out his MH to charge everything via solar and engine charging ,
     
  17. tonyidle

    tonyidle Funster

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  18. TheBig1

    TheBig1 Funster Life Member

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  19. Don Quixote

    Don Quixote Funster

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    I'm I great believer in "KISS" and as @hilldweller has suggested the 300watt inverter is what you want and will do the job. Hard wired to your LB's and NEVER to your VB.
     
  20. Bilbo Baggins

    Bilbo Baggins Funster

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    Thanks for all these replies. Certainly given me some options to consider. Only running a small van, a Autocruise Rhythm and carry the scooter on a rear mounted platform. The battery pack is easily removed and usually charges within an hour, with it's mains charger. Thanks again
     

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