Charging Amp drop from 40 amps to 24 amps

Charging Amp drop from 40 amps to 24 amps

Until a few weeks ago, my Model X (and Model S beforehand) always charged at 40 amps. Now, it seems to only charge at 24 amps. Have not made any changes to our home electrical system. Have Solar City/Tesla solar, with 2 Powerwalls, so all power is fed from solar or Powerwall, with almost no grid usage. Anyone have similar issue? Any idea on why this happened? Have tried to get answer from Tesla, but no response. Thanks!

Vawlkus | 2019年8月27日

Did you try charging the amps setting on the charging screen?

Passion2Fly | 2019年8月27日

Yes, Tesla changed some settings with their latest updates. This is mostly for the Gen1 portable chargers with the higher 40A charge limit. It might have to do with the battery fires in China... my Model X now defaults to 30A and I need to manually move the charge current up to 40A... funny thing is that my Model 3 defaults to 40A with the same charger!

volefen | 2019年8月27日

my car is in service right now and I asked my Tesla service advisor about upgrades. He said that they don't have any plans how and when it will be done as of yet. He has told me he heard that some small group of AP2 were invited for trial upgrades. Supposedly emails are being sent randomly to small group of AP2 asking to set up upgrades. I asked if he can put me down on the list but he said that he has no access...

ebender888 | 2019年8月29日

i always make sure it is set to 40 amp when i'm getting ready to charge. Once connected, it drops to 24 amps and no way to increase. Spoke with Tesla service and they're researching my MX history to see if they can determine the cause. Will update if they ever get back to me.

Vawlkus | 2019年8月30日

No messages on your dash when the drop occurs? Mine did something similar with certain local chargers that aren’t grounded properly.

Pungoteague_Dave | 2019年8月30日

"so all power is fed from solar or Powerwall, with almost no grid usage."

All power on such systems is grid-regulated. You do not receive power directly from your panels or batteries unless off-grid entirely. With a grid-connected system you supply power with your panels and battery, but all power usage effectively comes from the grid

Vawlkus | 2019年8月31日

Not always the case Dave.

I’ve seen a couple of the installation videos, and the grid is always upstream from the panels and powerwall.
The Teslanomics video lays it out the best, with the panels feeding the powerwalls, and the powerwalls supplying the house. Only if the powerwall can’t supply the house, does it draw from the grid.
Once the powerwall is fully charged, the powerwall starts to feed the grid power from the solar cells.

Pungoteague_Dave | 2019年9月1日

Incorrect Vawlkus - I have a 32kwh solar array (124 panels). Yes, the solar production is inboard from the meter, and hence the electrical grid. However, all balancing and control of NET metering occurs using grid-supplied electricity. The powerwall and solar panels are "dumb" systems that simply feed power in as available. This is why it is silly for folks to state that their car drives using solar electricity. Our system is supporting an oyster aquaculture operation with large pumps running 24/7, and it easily handles the rest of our property's systems, netting us over $30k annually in net meter reimbursements and SREC payments. My Tesla's tags read "SUN NRG". But it is all a lie. Even though we produce about twice our actual usage via solar, the fact remains that every single kwh of power used on our property is generated by an offsite power plant, most likely 75%+ coal. Because net metering is just that - when you add a new load to your existing powerwall or solar panel array, such as plugging in your car, a power plant somewhere suddenly works just that much harder, producing carbon outputs. We all charge using mostly carbon-based fuels. | 2019年9月1日

@PD - Unless you live in the west. Most power is hydro, nuclear (which is slowly going away), geothermal, wind and solar. Zero coal or diesel now in our state, and occasional gas peaker plants, which are being replaced with solar/battery systems (also slowly). In my specific area, I'm 100% renewables 24/7, beyond my home solar array.

Really cool that you get payments from the utility for your home power generation. Ours will not pay anything if you generate more than you use, which sort of sucks.

mcdonalk | 2019年9月2日

Our Model S sometimes changes from 40A to 32A. I think that this happens during the summer since the AC system is switching on and off when the car is charging, and the resultant induced electrical noise may be detected by the car as an impairment. During other times of year when the AC does not run at night, the car charges at 40A.

Vawlkus | 2019年9月3日

Just because YOUR system is configured that way doesn’t mean all others are.

ebender888 | 2019年9月11日

In service today. They state that the new cables/adapters are capped at only 32 amps; previous cables were capped at 40 amps. Which is odd, as the charging screen indicates it can charge up to 48 amps, but that only applies if you buy the Tesla wall charger. Regardless, they could only get it to charge on their wall charger to 24 amps, so there is a problem with the vehicle. My problem is it will take them several days and they do not provide loaner cars anymore (without much discussion and dispute), but they provided an Uber credit (which should cover me for 2 day only). Wish service was like it was a few years ago when i had my MS85!

dschamis | 2020年2月4日

Anyone ever figure out what was going on here? My Model X all of a sudden is capped out at 24A at home (whereas my Model 3 sitting right next to it in the garage goes to 48A).

zumret | 2020年4月1日

From now if you wanna charge faster you need to have wall charger from tesla. On NEMA outlet car not allowing to go max amp.For example my 48A only can charge 32A. I complained to tesla dealer and they give to me new wall charger free of charge. Because its was not even one week of mine trade in old tesla for new ones.

n7142701886 | 2020年4月1日

I had this issue few times.
It fixed after I Reset charger: (Unplug charger from outlet and plug it again.) | 2020年4月2日

@zumret - To be clear to others, the MC Gen2 included with the cars has a 32 amp limit. Tesla does have a special NEMA 14-50 MC that handles 40 amps. It does not have changeable connectors. To get to 48 amps, you need a Tesla WC, and a 60 amp or larger circuit. Sounds like you exchanged an older WC for a newer one? Seems like the older one should have worked, but perhaps not. They are now on Gen3 WC.