1. Attachments are working again! Check out this thread for more details and to report any other bugs.

8A current limit - does it work on L2 chargers?

Discussion in 'Prime Plug-in Charging' started by AltPwr, Mar 31, 2017.

Tags:
  1. AltPwr

    AltPwr New Member

    Joined:
    Mar 19, 2017
    7
    8
    0
    Location:
    Michigan
    Vehicle:
    2017 Prius Prime
    Model:
    Plug-in Advanced
    I understand the 8A current limit (down from the nominal 12A) that we can set when charging from the supplied L1 (110V) charging cable, but will it also limit the AC (240VAC) current to 8A on a L2 charger that is capable of delivering the normal 16 or more amps. The power draw is negotiated between both the car and the charging stn, but I can't find any info about what the Prime does in that situation.

    I figure when I have the time (almost always), I want the lower charging current to maximize the battery's life.

    I need to use a hardwired L2 charger to get the cheap dual rate from the power company, rather than needing a quick charge. Also, anybody know of any L2 chargers (other than ChargePoint ??) that it are easy to tweak the max available current?

    NO flame wars about battery life vs charge current please... I am an electrical engineer and like to push things to their max.
     
  2. koryliss

    koryliss Junior Member

    Joined:
    Dec 31, 2016
    14
    29
    0
    Location:
    Zion Crossroads, VA
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    For L2 it is 16amps (page 125 of the manual.....)

    ) Charging.jpeg
     
    bisco likes this.
  3. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,571
    48,862
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    is the 8/12 option on the evse or the charger?
     
  4. priuscatprimeguy

    priuscatprimeguy Senior Member

    Joined:
    Nov 1, 2016
    2,730
    2,638
    0
    Location:
    Farmington Hills, Michigan
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    the charger
     
    bisco likes this.
  5. Lee Jay

    Lee Jay Senior Member

    Joined:
    Jun 25, 2009
    5,850
    4,017
    0
    Location:
    Westminster, Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    Someone else said yes, and that makes sense to me. Here's why.

    I think it's always set to 16A and the EVSE that comes with the car has its own limit set at 12A, which the car follows. If you plugged in a 16A 12V EVSE, I suspect you'd get 16A.

    If so, the limit is voltage independent which is why setting it to 8A would limit it for both source voltages.
     
  6. giora

    giora Senior Member

    Joined:
    Aug 28, 2010
    1,966
    729
    0
    Location:
    Herzliya, Israel. Car: Euro version GLI
    Vehicle:
    2013 Prius Plug-in
    Model:
    N/A
    The footnote #1 is for both options, so the answer is yes.
     
  7. AltPwr

    AltPwr New Member

    Joined:
    Mar 19, 2017
    7
    8
    0
    Location:
    Michigan
    Vehicle:
    2017 Prius Prime
    Model:
    Plug-in Advanced
    I can verify now (by experiment) that the 8A limit DOES apply to both 120 VAC, and 220/240 VAC Level 2 chargers.

    Next Q: Do any ChargePoint owners know if we can set a hard limit (via the phone link) of 8A or some other limit) at the sourcing charger?
    I can't seem to get a meaningful answer from ChargePoint, and even after registering and downloading their phone app, I can't get any useful info about direct charger settings. (Phone wants to link to their charger before even talking about setup details.)
     
  8. Samprocat

    Samprocat Active Member

    Joined:
    Jan 16, 2017
    491
    297
    0
    Location:
    Lincoln, NE
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    You will control max AMP in car setting..so it really doesn't matter what type of output is from L2 station....
    For your question on battery life charging with lower AMP that is not necessary...Toyota have built measure where it goes down for last 40 minutes to slow charge and if necessary doing cell balance....I'm also engineer and i have this recorded with my tools...
    Another thing to consider is battery is never charged more than 80-85 % of full charge....
    In my work related experience testing limits of Lithium battery this current is definitely on longevity side that Toyota have done...16 amp are good

    Posted via the PriusChat mobile app.
    And on Prius Prime 8 amp setting will affect L2 charge same way...i have 2 Prius Prime
     
    priuscatprimeguy likes this.
  9. Samprocat

    Samprocat Active Member

    Joined:
    Jan 16, 2017
    491
    297
    0
    Location:
    Lincoln, NE
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    No you can't control current on chargepoint ......it is done by communication between car charger and chargepoint station..you have to remember that some have 8.5 kw limit and if someone is pulling on one side 6.6 kw you will get on another leg only 1.9 kw

    Posted via the PriusChat mobile app.
     
    priuscatprimeguy likes this.
  10. PT Guy

    PT Guy Senior Member

    Joined:
    Nov 23, 2016
    1,074
    707
    0
    Location:
    Washington, the state
    Vehicle:
    2017 Prius Prime
    Model:
    Plug-in Advanced
    Can you give us (layman language) links for reference to charging current vs. the life of a lithium ion battery?
     
  11. Lee Jay

    Lee Jay Senior Member

    Joined:
    Jun 25, 2009
    5,850
    4,017
    0
    Location:
    Westminster, Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    It's true but irrelevant in this case because both charge rates are very slow (about 0.2C and 0.5C). Charge mode on the car appears to be around 1C, braking can probably be a lot more than that, and CHADEMO in Japan is well over 1C. Dropping the 0.2C 120V charge rate by a third will make no difference in battery longevity.
     
  12. vvillovv

    vvillovv Senior Member

    Joined:
    Mar 19, 2013
    3,493
    1,231
    1
    Location:
    NY
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Plus
    Unless there are ambient conditions - excessive heat or cold - and an owner still wants to charge during those conditions.
    Of course those are extreme conditions with warnings concerning charging in the owners manual, not typical charge scenarios.
    And charge mode will only charge up to 80% of primes charge limit which is around 60% of the packs actual limit
    and since the engine is running the pack is or should be benefiting from heat or a/c conditioning while in charge mode.
    As always ymmv
    ps: When using the 8amp charge setting, the charge time can be ( was in both my experiments ) doubled what the charge time was using the Max setting.
    So, like Lee Jay mentioned above :) both settings are just above trickle charge when compared to the rates other manufactures use.
    I think they are smart to use these limits for a forced air cooled pack as the pack can still cook itself or get freezer burn under certain conditions and or bad settings.
     
  13. Kevin PT

    Kevin PT New Member

    Joined:
    Dec 10, 2018
    1
    0
    0
    Location:
    Tracy CA
    Vehicle:
    2018 Prius Prime
    Model:
    Prime Premium
    Does anyone know if the Prius Prime would charge using 16 amps using a combination 120V/240V charger rated at 16 amp or if the Prius would just limit charging to 12amp? I would use it on a 120V, 20amp circuit.
    I know standard charger at 120V uses 12 amps, 240 V chargers would use 16amps. Wondering if this might speed up charging without investment of 240V line?

    Here is a link to a charger that can use 120V and 250V:


    Thanks for your reply. Newbie to the forum.. couldn't find answer to this in threads.
     
  14. Lee Jay

    Lee Jay Senior Member

    Joined:
    Jun 25, 2009
    5,850
    4,017
    0
    Location:
    Westminster, Colorado
    Vehicle:
    2017 Prius Prime
    Model:
    Prime Advanced
    It'll charge at up to 16A if the EVSE supports it, regardless of voltage. The EVSE that comes with the car only supports 12A because it only has 14AWG wire feeding it and because Toyota (rightly) assumes most people don't know the difference between at 15A and a 20A outlet.