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240v power output

Discussion in 'Gen 2 Prius Main Forum' started by Frijjj, Jun 11, 2022.

  1. Frijjj

    Frijjj Member

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    I live in the UK and our domestic electricity runs on 240v.
    If the HV battery runs on 240v can I just tap a fused spur off the HV battery to run a 13A appliance via a domestic socket as long as the engine is on and in neutral?
    I would be getting an auto/electrician to do the wiring as I don't know what I'm doing death is suboptimal to the learning process.
    I did a search but didn't find anything so if you know of a thread I should look at please point me in the direction.
    Many thanks
     
  2. rjparker

    rjparker Tu Humilde Sirviente

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    No, the hv battery is dc, your utility power is 50 hz ac. The easiest way is to buy a 1000 watt 12v to 240 vac 50 hz inverter. That would run up to 4 amps of load. If you have a 13 amp appliance at 240 vac you need well over 3000 watts, probably 4,000 watts minimum. Not easily viable directly from the Prius.

    You would run the engine in Park; Neutral does not allow hv battery charging.
     
    #2 rjparker, Jun 11, 2022
    Last edited: Jun 11, 2022
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  3. rjparker

    rjparker Tu Humilde Sirviente

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    #3 rjparker, Jun 11, 2022
    Last edited: Jun 11, 2022
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  4. Tombukt2

    Tombukt2 Senior Member

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    You're going to want a 2400 milliamp charger giving . I charge at 300 V DC or it might 330 or such .I have the Venice hybrid charger// discharger
     
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  5. Tombukt2

    Tombukt2 Senior Member

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    I have Rajs Venice hybrid charger discharger I believe it's set to 336V DC switch position 2 for gen 2 and 3 it's 2.4 A at those voltages . Works well
     
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  6. ChapmanF

    ChapmanF Senior Member

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    Were those maybe replies meant for some other thread that was about grid chargers?
     
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  7. Tombukt2

    Tombukt2 Senior Member

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    I thought he wanted to charge the DC HV battery with 240 volts ac 50 hertz current in Europe I don't think that's a good idea I was just saying that I have the Venice hybrid charger thingy that has three settings Honda Toyota and higher and it puts out 2.4 MAH DC. And me thinks it makes a difference AC DC makes a big difference . Wish I could charge off dryer outlet he he
     
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  8. Frijjj

    Frijjj Member

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    Thanks, the plug out power is probably what I was looking for but it's bulky and I don't need the 12v, 24v or 120v capability. 5kw is definitely enough though. The price makes it cheaper to buy a separate petrol or diesel generator.

    Yes park is the one, not neutral oops that could have been a bad mistake and a jump start later!

    I need a DC / AC converter then, that would keep the voltage the same and wouldn't have to step up or step down. The 12v isn't powerful enough for what I was considering. I'll have a look and see what's available and if nothing then a separate generator is the answer.

    I don't want to charge the cars battery, I want to use the car to power normal devices I have in the home instead of using a fuel powered generator. The plug out power system is a large version of what I'm looking at but it's got a lot of ability that I won't use and it's expensive
     
  9. ChapmanF

    ChapmanF Senior Member

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    Alas, that doesn't really end up simplifying an inverter. To make DC into AC requires a circuit that can produce different voltages. 240 volts AC RMS at 50 Hz just means an output voltage that goes smoothly from +340 volts down to −340 volts and back again, every fiftieth of a second. It has to be able to output +340, −340, and every voltage in between. So an inverter that does that isn't a lot easier or harder to build than one for some other output voltage.

    You can see one complexity of the 240 AC output, in that even if the battery gives you 240 DC (which it does when well charged), you need a hundred volts more to hit the peaks you want for the output waveform. So the inverter needs either some boost-converter circuitry under the hood, or a big transformer on its output (which is the big white box in the photo of the PlugOut Power system, above).
     
    #9 ChapmanF, Jun 12, 2022
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  10. rjparker

    rjparker Tu Humilde Sirviente

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    There are other considerations for home backup generators or dc to ac inverters especially for the larger sizes you desire.

    First is the fuel and its storage and availability.
    A large load could burn through ten or more gallons a day. Storage of petrol or diesel can be an issue due to fuel aging and the volume needed. Around here, whole house backup generators are supplied with propane or natural gas. The generator carburetors don't get gummed up and fuel stays fresh. Propane can be stored onsite in a 250-1000 gallon tank without degradation. With the Prius solution you may have 12 gallons of fresh gas if you were lucky enough to top it off prior to the outage. At least the Prius has fuel injection instead of a carburetor and is highly likely to start when needed.

    Second is the power output.
    The low cost dc to ac inverters that sound like a great deal usually have a modified sine wave that may be bad on your electronics and ac motor loads. So better dc to ac inverters offer "pure sine wave" outputs. The best inverters are also more efficient and waste less battery power.

    E6DB248B-69E2-485E-BA7D-1AEF60B9B3D6.jpeg

    Lower cost generators have decent sine waves but vary significantly in voltage as loads change. Better conventional generators are well oversized to minimize voltage fluctuations. Modern generators now offer inverters to more precisely output a pure sine wave with very stable voltage. Otherwise most mainstream whole house motor generators are large at 10k-20k watts. These generally run $8k-$15k plus installation.

    Third is a transfer switch for large systems.
    When you want to run many circuit breakers worth of loads, the proper and safe way is with a transfer switch. Essentially it is a big power relay or manual switch inside a new panel that allows some or all of your circuit breakers to be switched to and from the backup power. Most well designed systems have automatic load transfer and start the generator or inverter system. These automatic functions also test the generator on a timed basis to ensure it will work two years from now when the storm hits.

    Fire and High Voltage Risks
    Some people reduce the cost by employing illegal hacks to backfeed generator power into the house but they can overload circuits and send power back to the grid in an extremely dangerous manner. There are other considerations as well but larger diy systems are tricky. Even the Prius plugout is risky since direct high voltage dc must be quickly accessed to use it. So non standard wiring and or quick connects might be employed.

    My Choice for Backup Power
    For my money a 1000 watt 12v to ac inverter is enough for the Prius. With that, most furnaces and refrigerators could be temporarily run in our Texas week long ice storms. Hopefully I have enough gasoline in the Prius because I could not get to the gas station even if they had power. A well engineered whole house propane or natural gas generator would be my choice for residential backup.

     
    #10 rjparker, Jun 12, 2022
    Last edited: Jun 12, 2022
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  11. ChapmanF

    ChapmanF Senior Member

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    :D

    As the illustration shows, a better way to read "MSW" would be "modified square wave", and the closest it ever gets to a sine wave is when somebody from the art department draws one next to it in an illustration like that.

    Just a square wave that loiters at zero a little bit every time it crosses.