charging configuration

[gbergman]

Hi:

I have a Tesla Y and Chevy Volt using older (non-wi-fi) Bosch and Clipper Creek J1772 EVSEs.
They're on a single 40amp circuit, so I can't charge both cars at the same time.
My electric rates drop to 5 cents per kWh between 9pm and 7am weekdays.
The Volt is programmed to charge from 9pm to 12:15am (to fill an empty tank). But, I can't figure out how to set the Tesla to start charging at 12:20am and stop at 7am, regardless of how much more it can use.

I found a free IOS app called “Optiwatt” which claims to control and monitor all aspects of charging a Tesla. I configured it with a fake off-peak schedule of 1am -7am (only supports 1 hour increments.)

Since the Chevy Volt maxes out at 16amps, another option is to limit the Tesla to 24 amps and let it charge from 9pm to 7am.
But, I still can't figure out how to set both a start and end time for the Tesla.

Assuming Optiwatt can start-stop the Tesla at those times, I haven't done the math to determine the better method, (5 hours at 40 amps or 10 hours at 24 amps)

Another anomaly is the Tesla keeps resetting the max charge to 50%. I'll need it for a long trip in a few weeks. Hope to solve that by then.

Thanks,
Gary

The difference between hardware and software: If you fool around with it long enough, software works and hardware breaks.

 

[Watts_Up]

Depending of your DIY electrical skills, and also to avoid using an App like “Optiwatt” requiring accessing your Tesla account...

One possibility would be to use separate chargers for each car, such as the Clipper Creek to charge the Volt and the Tesla UMC for the Model Y.

I would then use a relay to switch the power at a given time from the Clipper Creek (default) to the UMC charger.

If you use a NEMA 14-30 for the Tesla with the corresponding Tesla adapter, you will not have to worry about the 30 A (24 A nominal) setting.

I assume that your wall has a NEMA 14-50 receptacle so you will need to find the corresponding plug and receptacle.

Example of Timer: myTouchSmart 24-Hour in-Wall Digital Timer, 4 Programmable Easy On/Off Buttons

Note: Some timer provide separate programs for different days of the week, to solve your weekend need concern.

Example of Relay: TWTADE/JQX-62F-2Z Coil Voltage AC 110V 80A DPDT Electronmagnetic Relay,High Power Relay AC 110V

You could use a connection box, to install the Relay, the Timer, and to connect the wires together in a clean and safe manner,

such as: BUD Industries JB-3957-KO Steel NEMA 1 Sheet Metal Junction Box with Knockout and Lift-Off Screw Cover, 8" x 8" x 4", Gray Finish

 

[spokey]

Hi:

I have a Tesla Y and Chevy Volt using older (non-wi-fi) Bosch and Clipper Creek J1772 EVSEs.
They're on a single 40amp circuit, so I can't charge both cars at the same time.
My electric rates drop to 5 cents per kWh between 9pm and 7am weekdays.
The Volt is programmed to charge from 9pm to 12:15am (to fill an empty tank). But, I can't figure out how to set the Tesla to start charging at 12:20am and stop at 7am, regardless of how much more it can use.

I found a free IOS app called “Optiwatt” which claims to control and monitor all aspects of charging a Tesla. I configured it with a fake off-peak schedule of 1am -7am (only supports 1 hour increments.)

Since the Chevy Volt maxes out at 16amps, another option is to limit the Tesla to 24 amps and let it charge from 9pm to 7am.
But, I still can't figure out how to set both a start and end time for the Tesla.

Assuming Optiwatt can start-stop the Tesla at those times, I haven't done the math to determine the better method, (5 hours at 40 amps or 10 hours at 24 amps)

Another anomaly is the Tesla keeps resetting the max charge to 50%. I'll need it for a long trip in a few weeks. Hope to solve that by then.

Thanks,
Gary

The difference between hardware and software: If you fool around with it long enough, software works and hardware breaks.

Sounds like having both plugged in (physically) is not the issue.

If you use Teslafi, set a schedule to crank the charge limit up to say 90% at 9PM and another to drop to some obviously lower than you need limit before 7AM. Say maybe 50%. For the trip, add another entry to do a one-time 100% starting at whatever time seems appropriate. That scheduled change limit happens once and then deactivate. Keep it around if you want to activate next time or delete it.

They have a 2 week trial. But you can use my referral code Sign Up to get a trial month. Or anyone else' teslafi code. If you have a friend on it, they can give you one.

I've occasionally had trouble setting the power/amp limit in the car. I usually set it go out and come back in to see if it 'stuck'. I dropped mine from 30A to 12A figuring if I didn't need it, the lower made for a happier battery. But I don't do a lot of daily driving.

 

[Puma2020]

On the main screen in the car, you can go to the icon (I think it is the same as getting the entertainment) and you should see a charging sub icon.
Clicking that should bring up the charging time (at the bottom). That is also where you can switch from scheduled charging to schedule departure. Sadly you can only have 1 of them selected. Set the scheduled charging to the closest allowed time for it to start charging.
Page 167 of the owner's manual

 

[jcanoe]

You can set the Tesla to use Scheduled Charging. This is done from the Charging screen from inside the Tesla vehicle (you can't set Scheduled Charging using the Tesla App.)

You can specify the start/end of the Scheduled Charging window to align with off-peak rate hours. Tesla updated the Scheduled Charging software so that now you can set the end of the off-peak rate period (previously this was hard coded to be 0600 your local time.) You can set the Tesla vehicle to start charging at the beginning of the Scheduled Charging window, else charging will start as late as possible but still complete by the end of the off peak charging window. I.e., if you set the end of the off-peak rate to 0700 the Tesla will compute when to start charging so that charging will always be completed just before 0700.

A related setting is Scheduled Departure. This is also set from the Charging screen. Scheduled Departure enables you to precondition the Tesla vehicle before your usual departure time. Depending on the temperature outside or inside your garage which will affect the temperature of the battery pack, the Tesla may automatically warm the battery pack during the preconditioning period as well as warm the passenger cabin. You can set Scheduled Departure to be active every day or only on week days. You can also have Scheduled Departure precondition the Tesla even if not plugged in. One issue is that if you leave at 0730 and the off-peak rate period ends at 0700 when the preconditioning starts this will be during a peak rate time. Preconditioning will typically start 20 to 30 minutes before the Scheduled Departure time and will continue to run the climate control system for a period of time, perhaps 30 minutes after the Scheduled Departure time if you don't start driving precisely at the set departure time.

 

[Watts_Up]

They're on a single 40amp circuit, so I can't charge both cars at the same time.

Sounds like having both plugged in (physically) is not the issue.

Well, it would be interesting to know the electrical configuration, a picture could be useful.

However, you cannot have two chargers (a Bosh and a Clipper Creek) sharing the same circuit breaker,
unless like the Tesla Wall chargers which can be shared using a communication line?

 

[BenTheWriter]

Hi:

I have a Tesla Y and Chevy Volt using older (non-wi-fi) Bosch and Clipper Creek J1772 EVSEs.
They're on a single 40amp circuit, so I can't charge both cars at the same time.
My electric rates drop to 5 cents per kWh between 9pm and 7am weekdays.
The Volt is programmed to charge from 9pm to 12:15am (to fill an empty tank). But, I can't figure out how to set the Tesla to start charging at 12:20am and stop at 7am, regardless of how much more it can use.

I found a free IOS app called “Optiwatt” which claims to control and monitor all aspects of charging a Tesla. I configured it with a fake off-peak schedule of 1am -7am (only supports 1 hour increments.)

Since the Chevy Volt maxes out at 16amps, another option is to limit the Tesla to 24 amps and let it charge from 9pm to 7am.
But, I still can't figure out how to set both a start and end time for the Tesla.

Assuming Optiwatt can start-stop the Tesla at those times, I haven't done the math to determine the better method, (5 hours at 40 amps or 10 hours at 24 amps)

Another anomaly is the Tesla keeps resetting the max charge to 50%. I'll need it for a long trip in a few weeks. Hope to solve that by then.

Thanks,
Gary

The difference between hardware and software: If you fool around with it long enough, software works and hardware breaks.

Hi gberman,

I am from Optiwatt and with the anomaly with it charging to 50 percent it is a temporary thing. Optiwatt throttles your charges by setting this 50% limit during the shoulder and peak rates on your TOU plan, and will resume charging during the lowest electricity rates. By using a 50% limit, Optiwatt ensures your car doesn't automatically resume charging until the rates are cheapest.

 

[gbergman]

Hi gberman,

I am from Optiwatt and with the anomaly with it charging to 50 percent it is a temporary thing.

Oh! You're the culprit! In my case that's a dumb idea. I need to be in control of the max charge. If I'm not planning a trip I want the car to start charging at 12:45 am and stop at 7am to 80% charge (or less if not enough time). If I'm planning a trip, I will unplug the Volt,, start charging at 9pm, and stop at 7am or 100%.

How can I disable that 50% thing? Will logging out of the app do it?

Gary

Analyst to programmer: You start coding. I'll find out what they want.

 

[gbergman]

Well, it would be interesting to know the electrical configuration, a picture could be useful.

As stated. Both chargers are fed (in parallel) from the same 40amp breaker. I had used my Chevy Volt and prior Bolt to charge at different times during off-peak hours.
I replaced the Bolt with Tesla Y and want the Y to do the same thing (start charging at 12:45 and stop at 7am or less) unless I override it for a trip.

You cant' have both on the same breaker.

Yes you can if the cars don't request charging at the same time. (at least that's how the Chevys worked)

Gary

If I'm ever on life support, unplug me... Then plug me back in... See if that works.

 

[KurtSanders]

The Stats app for Tesla (for a one time purchase and no monthly subscription) also has a smart scheduled charging feature that could handle this situation along with lots of other features, controls, gauges, and usage statistics, graphs, etc...

Looks like you could start charging at 12:30AM and after two hours decrease the charge limit to whatever percentage you desire it to be before the peak rate charge changes!

 

[BenTheWriter]

Oh! You're the culprit! In my case that's a dumb idea. I need to be in control of the max charge. If I'm not planning a trip I want the car to start charging at 12:45 am and stop at 7am to 80% charge (or less if not enough time). If I'm planning a trip, I will unplug the Volt,, start charging at 9pm, and stop at 7am or 100%.

How can I disable that 50% thing? Will logging out of the app do it?

Gary

Analyst to programmer: You start coding. I'll find out what they want.

Hi gberman,
If you want you can disable the charge scheduler and it will charge based on the vehicles charge schedule.

 

[Watt_Sparky]

Hi gberman,
If you want you can disable the charge scheduler and it will charge based on the vehicles charge schedule.

Hi Ben,

Please let new users know this. I had to learn the hard way (getting up several times to make sure the limit was set correctly and trying to figure out why the limit was changing).

@BenTheWriter - Thanks

 

[BenTheWriter]

Hi Ben,

Please let new users know this. I had to learn the hard way (getting up several times to make sure the limit was set correctly and trying to figure out why the limit was changing).

@BenTheWriter - Thanks

I do let any users know about this so they do not have to try to trouble shoot on their own. Also our new redesign is coming in a month or two and it should remedy the issue of the charge schedule.

 

[orion2001]

Yes you can if the cars don't request charging at the same time. (at least that's how the Chevys worked)

I'm pretty sure that is a code violation. I don't believe you can have multiple EVSEs on the same 40A line even if you manually configure them to limit their max current draw. The only exception to that are the EVSEs specifically designed for powersharing that can communicate with each other and ensure they don't exceed the max safe current draw for that line.

 

[jsight]

How often is this actually a problem if you just set the Tesla to start at 12:30? It seems to me that this would add about 60% to the state of charge. Assuming that you have a charge limit of 90%, this would only become an issue when arriving with less than 30%. Is this something that happens often enough to be a problem? And might you just set a lower charge limit on the times when it does happen?

Note that I'm assuming by "40 amp circuit" you mean an actual charge rate of 32 amps (80% load factor). If you actually meant a 40 amp charge rate, then you can add ~80% in this time frame. I can't imagine that ever being a real issue to the point that you'd need to worry about the end time?