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How to make charging stop at certain time

Discussion in 'Prime Plug-in Charging' started by PiPLosAngeles, Apr 3, 2021.

  1. PiPLosAngeles

    PiPLosAngeles Senior Member

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    How do I set the car to stop charging at a certain time even if the car isn't to 100% yet?

    Sometimes I can't plug the car in until it's too late to get a 100% charge before the scheduled departure time, but because of my electricity rates I do not want it to continue charging past that time no matter what. I can't seem to find a way to make that happen. No matter how I set up the schedules, the charging continues past the departure time if the car hasn't reached 100% yet. It's not a simple matter of walking out to unplug it since I'm sometimes not at home to do it, or it's while I'm asleep.
     
  2. schja01

    schja01 One of very few in Chicagoland

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    Physical timer on the charge outlet/circuit.
    They make plug-in and in-line models.
     
  3. PiPLosAngeles

    PiPLosAngeles Senior Member

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    Thanks. No can do. It's on outdoor outlet, which requires one of these:

    [​IMG]

    If the car can't schedule charging, I just have to avoid charging on those days. Seems a shame to use gas when I could have used electricity.
     
  4. schja01

    schja01 One of very few in Chicagoland

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    If that’s a dedicated circuit you can install a timer on the breaker box.
     
  5. PiPLosAngeles

    PiPLosAngeles Senior Member

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    It's not dedicated, but even still I don't think the time and expense is worth it. I just hoped Toyota had proper scheduling. Not yet, it seems.

    One thing the Leaf had was a setting called something like "Full charge priority." If it was set it would behave like the Prius, but if it wasn't set charging would terminate at the set time regardless of SOC.
     
  6. dbstoo

    dbstoo Senior Member

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    I'm also on a TOU rate, so thanks for mentioning this. I have not checked to see what happens if I'm charging at 3 PM when I have it set for departure. I use a level 2 charger, so it charges in around 2 hours if empty. I charge whenever parked at home and I'm seldom less than 60% SOC so if I park it at 2:30 the car will still finish on time. That's a long way of saying that I've never gone out to check to see if it's charging at 3:05. :)
     
    #6 dbstoo, Apr 3, 2021
    Last edited: Apr 3, 2021
  7. PiPLosAngeles

    PiPLosAngeles Senior Member

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    It is. Unfortunately my rates quadruple at specific times, so Level 2 charging for only 30 minutes past the rate change will cost as much as the 2 hours of charging before.

    The car is an amazing piece of technology with some truly bizarre oversights.
     
    #7 PiPLosAngeles, Apr 3, 2021
    Last edited: Apr 3, 2021
  8. Salamander_King

    Salamander_King Senior Member

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    I think you can use an outdoor timer switch like this.
    Screenshot 2021-04-03 10.01.02 PM.png



    Or, if you want more precise control, you can use an outdoor smart plug like this. As long as it is rated 15A, it should work on Toyota OEM L1 EVSE.
    upload_2021-4-3_22-3-49.png
     
    #8 Salamander_King, Apr 3, 2021
    Last edited: Apr 3, 2021
  9. PiPLosAngeles

    PiPLosAngeles Senior Member

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    Thank you. Something like that might work.
     
  10. sam spade 2

    sam spade 2 Senior Member

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    It seems that you are saying that it is somehow charging TOO MUCH.
    I don't understand that.
    It is only a problem if the charging current costs you MORE than an equivalent amount of gas.
    And if it doesn't happen often and the duration isn't very long, then it seems that you might be making a mountain out of an ant hill.
     
  11. PiPLosAngeles

    PiPLosAngeles Senior Member

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    Yes.

    My electricity at peak rates is $0.52/kWh. At the PP's rated 25 miles per ~6.5 kWh it takes about 14 kWh to drive the same distance as a gallon of gas. In my case that's the equivalent of $7.44 per gallon.

    It happens a couple of times per week that I arrive home with maybe an hour or two left before peak rates begin and I want to charge until then. It's not a huge deal, just an oversight on Toyota's part.
     
  12. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    With a 4x rate multiplier I think I'd want a proper timer on the supply circuit rather than trusting that the car (or the next car etc) had the feature built in.

    But if we are still playing feature wishes, I can't believe they didn't make the charging system coherent for block heaters- charge the battery first, then divert the power to the block heater so you don't have to use two cords to plug the car in twice.
     
  13. Salamander_King

    Salamander_King Senior Member

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    What block heater are you talking about? Engine block heater? Has there been any car that had an integrated engine block heater system?
     
  14. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    It's an option (supported by Toyota-made and -sold parts) on (afaik) every single Toyota that is offered with a PHEV powertrain. Granted, it's not a popular option but I think they had a chance to set the standard for how this stuff should interact, and I don't they didn't did very well.
     
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  15. PiPLosAngeles

    PiPLosAngeles Senior Member

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    As far as I know, Toyota is the only one that doesn't have it.
     
  16. Salamander_King

    Salamander_King Senior Member

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    The engine block heater is not a factory option in the USA at least not in the lower 48 states, maybe in Alaska? I believe it is an option for a Canadian market. I tried to install one on my 2017 PP at my dealer, but that was not even a dealer-installed option then, just a separate installation. In the end, I found out most people living in colder climate did not find it necessary to have the engine block heater installed, so I did not get one.
     
  17. PiPLosAngeles

    PiPLosAngeles Senior Member

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    I think it's more important for Diesel? Back in my college days I parked outside in -40°F weather and never had any problem with my car not starting on the first try.
     
  18. Salamander_King

    Salamander_King Senior Member

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    Yeah, back in my college days my first used car I purchased had a dangling AC cord out from a grille. I had no idea what that cord was used for then. I never plugged it into anything. Never had a problem staring that car (4 cylinder gas engine Chevy Vega) at -40°F temperature. Supposedly, for PP in a colder climate, the EBH will help the engine to warm up quickly to give more cabin heat when the heat pump does not work and save gas somewhat. But I did not think it would be cost-effective in our region with a higher electricity rate, so I did not install one.
     
  19. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    First an acknowledgement, you are correct- the necessity of block heaters has greatly dwindled with the advent of electronic fuel injection.

    Next, I've read many accounts of significant efforts made by Prius owners to avoid, minimize, or diminish the warm-up cycle of the gas engine.

    I think it might be better to attack it the other way: preheat it on cheap grid electricity so you don't have to burn as much gas to hit the target.

    This is still inconvenient in a regular hybrid, the benefit is a bit thin compared to the work of plugging in.

    Enter the PHEV! You're going to plug it in anyway, right?

    So why not include a "thru" tap on the charger inlet such that a block heater could be connected to it? Ideally it would be managed by the car's charger logic, timed and sequenced appropriately and so forth.

    I don't imagine that every owner would gain a real benefit from a grid preheated block, but I'm certain some would. I'd love to see real data on that.
     
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  20. Salamander_King

    Salamander_King Senior Member

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    Yeah, I follow your logic. It would be nice if Toyota figures out such an option to be built in. I would even suggest having an onboard 12v battery charger integrated into the charge session as long as Toyota designs PP with a separate 12v battery that does not get charged while being plugged in for the traction battery charging.

    That being said, my point was that, currently, Toyota does not offer an EBH option on PP at least in the lower 48 states. Also, for our region, the grid power costs more than gas, so I am not so sure using more electricity will save any money by avoiding the initial engine warm-up cycle.

    Moreover, I think the EBH is less effective to prevent or shorten the engine warm-up cycle in PHEV like PP compared to a regular hybrid. In my experience, if I charge my PP in a dead of winter and start the car, as long as I have set the heater to be OFF, the engine will not start immediately unlike the regular Prius. Only if I turn on the defroster or turn on the heater when the ambient temp is below 14F, then the engine will fire up. I can have the car start on default EV mode with the heater set to OFF position, and if I don't use the defroster, I can start driving the car in EV mode even at a temperature below 14F. In this scenario, EBH would serve no function, the engine would be start cooling as soon as I unplug EBH and drive off on EV mode. When the engine fire-up is called for either for traction or heat a few miles down a road, it is already cold.
     
    #20 Salamander_King, Apr 5, 2021
    Last edited: Apr 5, 2021