240volts @ 10amps charge possible?

[moonfresh]

Wow! That is amazing!

So how do you charge control the Lithium batteries? I would assume off the shelf stuff would not be setup for that? Most charge controllers are built for lead acid...

Also, what battery string voltage are you running?

I will post a different thread later on today with details. It will be titled: Boondock Power Storage for M3...something like that.

 

[mspohr]

You might want to check out OpenEVSE | Home
Their charger has an API where you can adjust time of charging as well as charge rate so you could tailor it to power available.

 

[dhanson865]

Charging efficiency decreases for lower charging power, so you may not want to lower the amperage too low if the total energy consumed matters to you. I've seen efficiency vs. amperage data on one of the Tesla forums, but I can't find it right now.

@moonfresh

240v is more efficient than 120v. Total power will determine efficiency it may be that 8A is more efficient than 10A, he'll have to test every 2A. Since he wants to stay at or under 10A he only has to test 3 options

* 6A
* 8A
* 10A

One of those will be most efficient. Likely 10 or 8 but you'd have to test to see. But really the difference in efficiency between the 3 is almost nothing. I wouldn't waste a ton of effort testing if 10A works. I also wouldn't hesitate to step down to 8A or 6A if you feel like it for any reason. Use whatever level you want.

 

[brucet999]

Wow! Impressive!

So does that mean the grid is available, but you just don't normally use it? This is an interesting scenario. I would say this is an expensive way to charge the car! Panels + battery and inverter and all!

So in an optimal world you would take solar and just put it straight into the car (avoiding losses putting the power into what I presume are lead acid batteries and then pulling them back out). But the car is not really set up to handle this.

One interesting option would be if someone made a unit that could vary the pilot signal to the car to vary the amps of charge to only charge during solar production hours. (though you may not have the car at home at the right time of day for that)

But that is not the question you asked:

I wonder if getting a NEMA 6-15 adapter for the UMC Gen 2 would make sense so that even if you accidentally forgot to crank down the charge amps it would only pull 12 amps. That, or install a wall connector and crank it all the way down to the lowest setting of 12 amps.

If M3 charging setup is like MS, once one sets the charge rate it will remember that limit for that location, and always charge at the reduced rate there until charge rate is again manually set. Charge rate at other locations would go to default settings.

 

[tga]

Also, there is an inverter that can take solar and directly charge an EV without having a battery bank.

Which one? The SolarEdge, or a different one?

 

[eprosenx]

If M3 charging setup is like MS, once one sets the charge rate it will remember that limit for that location, and always charge at the reduced rate there until charge rate is again manually set. Charge rate at other locations would go to default settings.

This has been known to fail with software updates, etc... So I would not rely on it to always work.

 

[mspohr]

Which one? The SolarEdge, or a different one?

I have a SMA Sunny Boy Inverter which can output 120v 2000 W directly from the solar panels if the grid is disconnected.

 

[Dave EV]

You might want to check out OpenEVSE | Home
Their charger has an API where you can adjust time of charging as well as charge rate so you could tailor it to power available.

Yep - if you use it in conjunction with OpenEnergyMonitor, you can dynamically adjust your charge rate to what your solar system is producing as well.

 

[moonfresh]

Which one? The SolarEdge, or a different one?

I posted my Boodock Solar shed thread.

 

[moonfresh]

Which one? The SolarEdge, or a different one?

I think my friends are using MPPSolar...

 

[tga]

I posted my Boodock Solar shed thread.

To make it easy for people following this thread: BoodockSolar Charger for M3