Cheaper to charge at 240 than 120?

Discussion in 'Prime Plug-in Charging' started by stevepea, May 12, 2017.

  1. Trollbait

    Trollbait It's a D&D thing

    Joined:
    Feb 7, 2006
    14,619
    6,441
    0
    Location:
    eastern Pennsylvania
    Vehicle:
    Other Non-Hybrid
    The Prime pulls under 20 amps, but if you are going to run the electric cable for a level 2, might as well run a 40 or 50 amp rated one for the ability to support BEVs down the road.
     
    HPrimeAdvanced and vvillovv like this.
  2. ArcPrime

    ArcPrime Active Member

    Joined:
    Apr 28, 2017
    201
    164
    0
    Location:
    Arcadia, California
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    I don't count the last 10 minutes I only counted the flat steady charge that's why I stop @ 2 hours before it's fully charged. I went to a few different ChargePoint L2 station charged time between 1-2 hours to have partial charge all at 13AMP.
     
  3. Lee Jay

    Lee Jay Senior Member

    Joined:
    Jun 25, 2009
    4,913
    3,542
    0
    Location:
    Westminster, Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Well, maybe a ChargePoint issue. The car will draw 16A.

    And the taper charge at 240V is longer than 10 minutes. More like 20-30.
     
  4. Breatheintheair

    Joined:
    Feb 1, 2017
    45
    78
    0
    Location:
    Cary, IL
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    DavidA, I am having a 240v service installed tomorrow in the Chicago area. I'll let you know how it goes. Electrician was very reasonable and does installations for dealerships.

    Posted via the PriusChat mobile app.
     
    HPrimeAdvanced likes this.
  5. ArcPrime

    ArcPrime Active Member

    Joined:
    Apr 28, 2017
    201
    164
    0
    Location:
    Arcadia, California
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    Well maybe Prime charger can draw 16 AMP however my Prime drawed 13 AMP. 2 of my coworkers Fiat e500 used the same ChargePoint station can draw 30-32 AMPS. They will get over 7 KW per hour of charge.
     
  6. CharlesH

    CharlesH CA HOV Decal #5 on former PiP

    Joined:
    Nov 27, 2005
    2,546
    996
    0
    Location:
    Roseville, CA
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    On my home Chargepoint charger, the online report shows a charging rate of 3.6KW = 15A at 240 V. I didn't actually measure the voltage when the charging is happening, so that could be off. To accurately get the current, I need to measure the voltage while charging. I am assuming that the charger has a power factor of 1.0, so that watts = volts x amps. Several sites I looked at indicate that 0.99 is about where car chargers run, so volts x amps won't be far off.The activity log graphs the current draw over the period of the charging session, so you can get the current at any point during the charge.
     
    #46 CharlesH, May 21, 2017
    Last edited: May 21, 2017
  7. TDR Marine Engineer

    TDR Marine Engineer Junior Member

    Joined:
    Feb 22, 2018
    35
    23
    0
    Location:
    Florida
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    Sometimes the L2 charger unit can’t output the full amount. A wire in the cable can handle only so much current. The higher the voltage the more current it can carry safely. Amp ratings on products are a safety amount. Usually products are rated up to an amperage and for different voltages they will be different amperages. So, @120V the system can handle UP TO 12 amp and at 240V it can handle UP TO 16 amp. This doesn’t mean it will always take the full rated amperage. The car will reduce the charge rate based on temperature too. Many things play into how fast your car charges.
     
    HPrimeAdvanced likes this.
  8. TDR Marine Engineer

    TDR Marine Engineer Junior Member

    Joined:
    Feb 22, 2018
    35
    23
    0
    Location:
    Florida
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    The last bit of charge is important. The batteries in your car will heat up significantly as they get to max full if at full rate. Almost all batteries slow charge about the last 20%.

    This is why so many Tesla owners are so mad about the supercharger stations. They can only charge a certain percentage not the “Full Tank” at the super chargers in 20 min. If you don’t need the last 20% then just leave when the charge rate slows. If you do need it you should wait for the slow charge to complete.

    Now about the ChargePoint chargers; the units that free charge around me are limited to 6.6 kWh per plugin. If I need to charge more than that I have to unplug and restart the charge process.
     
  9. john1701a

    john1701a Prius Guru

    Joined:
    Jan 6, 2004
    11,741
    4,478
    57
    Location:
    Minnesota
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Huh?

    I've been using ChargePoint since 2012 and that has never been the case.
     
  10. Lee Jay

    Lee Jay Senior Member

    Joined:
    Jun 25, 2009
    4,913
    3,542
    0
    Location:
    Westminster, Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    All of what you just said is false.

    The L2 "charger unit" isn't a charger, it's a fancy extension cord. In this case, the most likely reason the power is lower than expected ("13*240/1000=3.12KW") is because the voltage wasn't 240V, but rather 208V (15A * 208V = 3.12kW). 208V is a commonly available voltage in commercial settings because it is the line-to-line voltage of a Y-connected system that has a line-to-neutral voltage of 120V (120V * sqrt(3) = 208V).

    Higher voltage enables a wire to carry more power, not more current. Ampacity is independent of voltage.
     
  11. TDR Marine Engineer

    TDR Marine Engineer Junior Member

    Joined:
    Feb 22, 2018
    35
    23
    0
    Location:
    Florida
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    American wire gauge (AWG), also known as the Brown & Sharpe wire gauge, is a logarithmicstepped standardized wire gauge system used since 1857 predominantly in North America for the diameters of round, solid, nonferrous, electricallyconducting wire. Dimensions of the wires are given in ASTM standard B 258.[1] The cross-sectional area of each gauge is an important factor for determining its current-carrying capacity.

    Wiring is not rated by wattage it is rated by amperes. Transformers are rated by VoltAmps which is almost wattage but takes into account more than pure power.

    You are correct that the ChargePoint and other “charger cords” are mostly just extension cords but they also use a sense circuit with low voltage to make sure the end user isn’t killed by the open leads before applying full current and voltage. I just unplugged mine from the car and tried to measure on the L1 - L2 N - PE and found no DC or AC voltage available. In fact the “charge cord” box clicks audibly a relay off to ensure it is not live when unplugged.

    I don’t suggest anyone actually go buy a cord and plug then directly wire it up to their breaker panel or even into an outlet such as a drier. This would be extremely dangerous to anyone using the cord without prior knowledge of it being a live plug. Particularly when plugging in while raining.

    Lastly as I said the vehicle (which is the real charging unit) is monitoring the battery temperature in most cases, as well as the charge level. It decides the current to use. If the current that the vehicle can use is less than what the charge station is able to provide the car will charge at a lower rate. The ChargePoint units can only handle so much power draw based on the voltage and amperage for safety reasons or limitations in the supply. Voltages available will be different based on your area. For instance I am able to use 240 in Raleigh, NC and 208 in Fayetteville, NC.
     
  12. TDR Marine Engineer

    TDR Marine Engineer Junior Member

    Joined:
    Feb 22, 2018
    35
    23
    0
    Location:
    Florida
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    Guess it depends on where you live.
     
  13. Lee Jay

    Lee Jay Senior Member

    Joined:
    Jun 25, 2009
    4,913
    3,542
    0
    Location:
    Westminster, Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Right, which is independent of voltage, just as I said.

    Called "apparent power", which includes both real power and reactive power.

    The charger is under the right-rear seat.

    Correct. It does this at the end of every charge.

    And we use 208V at work.
     
  14. john1701a

    john1701a Prius Guru

    Joined:
    Jan 6, 2004
    11,741
    4,478
    57
    Location:
    Minnesota
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Sounds like your specific location has an owner that set up an odd custom rule.

    What actually happens ?
     
  15. muleman

    muleman Junior Member

    Joined:
    Jan 10, 2018
    56
    47
    0
    Location:
    rochester ny
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    Really only benefit is you might be able to charge faster and take advantage of off peak discount prices. Plus a fast turn around. I can run around town full electric and come back home and get a full charge before I leave for work (24 mile trip).
     
    HPrimeAdvanced likes this.
  16. TDR Marine Engineer

    TDR Marine Engineer Junior Member

    Joined:
    Feb 22, 2018
    35
    23
    0
    Location:
    Florida
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    Full charge in less than 2 hrs.
     
    HPrimeAdvanced likes this.
  17. john1701a

    john1701a Prius Guru

    Joined:
    Jan 6, 2004
    11,741
    4,478
    57
    Location:
    Minnesota
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    That doesn't answer why you "have to unplug and restart the charge process."

    Is it just a slow charger? A normal one only takes 2 hours for a full charge anyway.
     
  18. TDR Marine Engineer

    TDR Marine Engineer Junior Member

    Joined:
    Feb 22, 2018
    35
    23
    0
    Location:
    Florida
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Premium
    I think it was my battery charge control in the car. I’ve been told by my dealer that my traction battery isn’t fully charging. I then tried replugging the charger at a charge point and it proceeded to charge more at full rate. Anyway it may be the particular unit I was using. Others have complained about it at the same location on the charge point app.

    Quick question do any of y’all who drive a prime hear a solid click/clunking noise from the front end that is in tune with tire rotation when hard turning at slow 35 miles per hour. Say at an off ramp? I also have strong cyclical noise when the windows are open. I think it’s a bad tire but I had them rotated and it’s still noticeable on new pavement.
     
  19. Oniki

    Oniki Active Member

    Joined:
    Jun 10, 2017
    652
    494
    0
    Location:
    Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    OP is probably long gone, but his question was never answered.

    L2 efficiency is ~ 87.5%
    L1 efficiency is ~ 82.0%

    An empty to full charge in the battery is ~ 5.5 kWh,

    So the L1 pulls 5.5/0.82 = 6.7 kWh
    and the L2 pulls 5.5/0.87 = 6.3 kWh
     
    #59 Oniki, Mar 2, 2018
    Last edited: Mar 2, 2018
    Trollbait and john1701a like this.
  20. Lee Jay

    Lee Jay Senior Member

    Joined:
    Jun 25, 2009
    4,913
    3,542
    0
    Location:
    Westminster, Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    I've repeatedly measured a full-charge in my Prime, and I got 6.3kWh on L1 and 6.3kWh on L2.
     
Loading...