GEN 3 load sharing question

[Ninja1000]

Hi all,

I have a simple question for anyone using two Gen3 wall connectors using the same circuit. I will be adding a second charger on my 60amp circuit.

My question is, when doing load sharing, If only one charge is in use, does it limit it to 24amps or can I get the 48 amps when required.

(I only charge at 25amps at night but there are times that I need a quicker charger so I crank it to 48amps.)

KC

 

[Cosmacelf]

You can indeed get 48A from one unit if needed assuming the other unit isn’t drawing any load.

 

[rwojo]

Why limit to 24? You should charge as fast as possible on AC charging for efficiency.

Also if a unit is plugged into a car but not actively charging it still reserves 6A I believe from the network limit.

 

[Ninja1000]

You can indeed get 48A from one unit if needed assuming the other unit isn’t drawing any load.

Thanks for the information.

 

[Ninja1000]

Why limit to 24? You should charge as fast as possible on AC charging for efficiency.

Also if a unit is plugged into a car but not actively charging it still reserves 6A I believe from the network limit.

How can it be more efficient charging at 48 instead of 24? At 24 it takes twice the time and typically puts less stress on a battery.

 

[rwojo]

How can it be more efficient charging at 48 instead of 24? At 24 it takes twice the time and typically puts less stress on a battery.

Components are not running for a longer duration sucking down 100W+ thus saving energy. You aren't even approaching any level of stress on the battery being below 1C at 48A. Only DC fast charging even approaches stress levels. Charge up at 48A to 80% or your poison and enjoy!

 

[Ninja1000]

Components are not running for a longer duration sucking down 100W+ thus saving energy. You aren't even approaching any level of stress on the battery being below 1C at 48A. Only DC fast charging even approaches stress levels. Charge up at 48A to 80% or your poison and enjoy!

Thanks, you are right on sucking a bit more current on 4 hours extra charging time. But I really doubt it comes even close to 100 watts, it's only a relay and a few electronics that is activated in the charger module and relays take little current. Anyway, thanks for the information, I wasn't here to argue .

 

[Cosmacelf]

Thanks, you are right on sucking a bit more current on 4 hours extra charging time. But I really doubt it comes even close to 100 watts, it's only a relay and a few electronics that is activated in the charger module and relays take little current. Anyway, thanks for the information, I wasn't here to argue .

Actually, it’s more like 300W. The car computer has to be on along with some minimal cooling, maybe a pump motor and maybe a fan. But it is still minimal in the big scheme of things. Now charging at 12A/120V is definitely more noticeably inefficient.

 

[rwojo]

True. 120V last resort, since I think it's around what 70% efficient? But yeah any 240V with sufficient amperage is going to be in the 90%+ range.

Then again, any charge is better than no charge!

 

[240vPlug]

Each charger should be on its own 60amp circuit per Tesla. They each share the amount of power allocated to the "site". For example I have two TWC and each is on their own 60 amp circuit. I have allocated 60 amps to the "site". What this means is that the chargers can draw up to 60 amps. One alone with charge at 48amps but if both are charging the most they can draw is 30amps each.

For inspection purposes it counts as a 60 amp load even though it's 120amps worth of circuit.

 

[fiehlsport]

How can it be more efficient charging at 48 instead of 24? At 24 it takes twice the time and typically puts less stress on a battery.

Level 2 charging, no matter what the rate, doesn't stress the battery at all. You're fine to charge at 12A or 48A - it's no different to the battery.

48A at home vs 250kW Supercharging - that's another story.

 

[h2ofun]

Each charger should be on its own 60amp circuit per Tesla. They each share the amount of power allocated to the "site". For example I have two TWC and each is on their own 60 amp circuit. I have allocated 60 amps to the "site". What this means is that the chargers can draw up to 60 amps. One alone with charge at 48amps but if both are charging the most they can draw is 30amps each.

For inspection purposes it counts as a 60 amp load even though it's 120amps worth of circuit.

I have 5 WC's on a 200 amp subpanel. I would never want to pull that much since my heat pumps are also on the same feed.
I got 3 of them sharing but found out unless you leave them on, the logic assumes the ones off are pulling max load so it kicked back the one I was using. So I turned off the sharing and would just let me decide what I would do if charging more than one at a time, which chances are about zero.