Yes, it does an impedance test. If it detects a high impedance line it will drop the charge amps and set the alert. It's even more sensitive on 208v vs 240v. 500 feet of #12 is really bad. You shouldn't be pulling more than 20A on #12 anyway, and at 500', that's unacceptable voltage drop even at only 20A. (about 17% even at only 20A!) Attempting to pull 30A is way outside of NEC limits! (30A would be 25% loss!!!)
On Fri, Sep 13, 2024 at 12:44 PM Cor van de Water via EV <ev@lists.evdl.org> wrote: > Maybe in interesting tidbit for Phil: > My Tesla (2013 S with dual charger) is charging again, but it still > complains about bad quality grid, immediately after I plug in, even > before ramping up the current. It also overrides the EVSE advertised > 40A and lowers it voluntarily to 30A as displayed on the dash. Since > it does this even before any current ramping and the grid voltage is a > healthy 211V (this is a commercial site with 208V grid), I am > suspecting that the *slave* charger (which is unused for charging at > 40A or less) also has a blown fuse and complains about not getting > power, thus triggering the same warning that I got when the main > charger fuse was blown. Unless the Tesla does some kind of impedance > test, because indeed the EVSE is connected with *very* long wiring so > the voltage drops to 197V when only ramping up to 24A because of > approx 500ft of 12 AWG wire in the loop. But it charges without > problem, just complains. > Do you have any advise? I plan to connect to a healthy 240V 48A > charger and verify if it indeed has trouble engaging the 2nd (slave) > charger. > It is time I have you re-enable DC charging. > Cor. > > On Sat, Jul 27, 2024 at 10:40 PM Cor van de Water > <cor.vandewa...@gmail.com> wrote: > > > > OK, did the charger swap today. > > I joined the ranks of owners of gen1 Tesla w dual chargers that blew an > input fuse. It seems to be an epidemic. > > To be sure I could just swap in a replacement for the master, I bought a > gen1 charger on Ebay. Packaging looked terrible when it arrived, the > mailman actually dumped it in front of my garage door, but I inspected it > and could not find damage, not even on the alu coolant lines sticking out, > so I was lucky. > > I had a former colleague and fellow Tesla nut give a hand. We figured > out a way to avoid spillage by lifting the old unit after disconnecting one > side, to drain it back into the coolant bottle and connect the replacemt > unit to the open line to let it fill its heatsink so in the end we lost > maybe an ounce of coolant, I did not even need to add coolant. > > The car charged happily as soon as I closed the power distribution box > with a screw next to the magnetic interlock. > > Really, the most difficult part of the whole thing was to remove the > Bolsters next to the rear seat back. I figured a way using the seatbelt > inserted on top of the clip and yanking on that to avoid bending them. > > The weirdest part was finding out Tesla used 11mm bolts for the rear > seat frame. > > Never before have I used 11mm on a car. > > You can completely disassemble a Prius with a set of 8, 10, 12 and 14mm, > with the vast majority of bolts being 10mm. > > > > Anyway, opening the old master charger revealed one of the two 50A > semiconductor fuses on the charger inlet to be blown. This seems to happen > more on cars with dual chargers, although before it failed I was never > charging at more than 40A. Maybe it is because the dual charger has the > coolant loop split into two, so each charger only gets half the coolant and > thus runs hotter than the single charger, because at up to 40A the slave > charger is not used, the full 40A is handled by the master, but it gets > only half the coolant that a single charger car sends through the loop. > > > > It seems that Ebay notices that a lot of 50A fuses are bought for these > broken chargers, because a 50A fuse costs $50 while the same model 60A fuse > costs $9. Go figure. > > Anyway, the car is back on the road and it cost me only some hours and > $140 for a used charger. Looking at the cost of the fuses, I got that > working charger for scrap value plus two good fuses! > > Cor. > > > > On Tue, Jul 16, 2024, 10:43 AM (-Phil-) <p...@ingineerix.com> wrote: > >> > >> The only issue with swapping is you still have to physically swap their > locations, so it involves opening the coolant loop. You then have to send > a CAN sequence using Tesla toolbox to swap them logically. Using some > hose clamp pliers you can usually do the coolant loop without spilling too > much, but it's still messy. Be sure to at least have a gallon of G48 > coolant on-hand before you start! > >> > >> For the cost, it's not worth swapping a bad unit. Just replace it. > >> > >> Yeah, I can re-enable supercharging on the old MCU units, but I might > have to downgrade software to do it. They have added more security lately. > >> > >> On Tue, Jul 16, 2024 at 10:36 AM Cor van de Water < > cor.vandewa...@gmail.com> wrote: > >>> > >>> Awesome, thanks for the info! > >>> I ordered a cheap used gen1 charger just to make sure that I can swap > >>> in a charger. > >>> Another thought I had: if the Master is broken and the Slave is good, > >>> then just swapping the two will again allow me to charge at up to 40A, > >>> right because only for over-40 Amps charging will the slave charger be > >>> activated. You can see that when connecting to a 48A charger, the > >>> current first runs up to 24A to dial in the Master charger, then it > >>> sits at 24 for a while, then it ramps up the Slave charger until the > >>> pair is drawing 48A combined. > >>> Anyway, will be digging into that soo to get this car back on the > >>> road. Then I will come to you for Supercharging re-enabling. > >>> Do you care if it still has the original computers? I did not want to > >>> invest $1500 or something like that just to upgrade to later version > >>> computers.while the car stays the same... > >>> Regards, > >>> Cor. > >>> > >>> On Mon, Jul 15, 2024 at 11:36 PM (-Phil-) <p...@ingineerix.com> wrote: > >>> > > >>> > The Gen1 chargers are not known to be the most reliable. Sounds > like a problem in the PFC stage. They are not very serviceable even if you > can do board-level repair due to their mechanical design. I suggest just > ordering a used one for a couple hundred $. > >>> > > >>> > If you wanted to save buying one, you could convert the existing > slave to a master, and move it to the passenger side, and remove the master > (so you'd be down to 40A max charging), but this requires some hassle > including altering the config so the car doesn't look for the 2nd slave > charger. > >>> > > >>> > It's also possible to upgrade to the Gen2 charger, but it would > require also replacing the HV junction box that contains the DCFC > contactors and some harnessing. > >>> > > >>> > On Mon, Jul 15, 2024 at 11:26 PM Cor van de Water via EV < > ev@lists.evdl.org> wrote: > >>> >> > >>> >> Hoping to find someone that has experience with the early Tesla > model S and > >>> >> X 40A onboard charger. > >>> >> My S85 actually has 2, having the ability to take up to 80A, up to > 20kW > >>> >> level 2 charging speed. > >>> >> But, recently it refuses to charge: everything seems ok when > plugging in, > >>> >> but after half a minute the car ramps the current up, as soon as it > even > >>> >> steps to 1 Amp, it fails with warning: "charging slowed - poor grid > power > >>> >> quality possible. Try different charging location. > >>> >> > >>> >> Well, no problem with the charging location, I have read that this > is > >>> >> likely a problem in the charger or the circuit feeding the AC to the > >>> >> charger. > >>> >> Before I rip my rear seat out to get to the dual chargers, I hope > someone > >>> >> has seen this behavior before and can give me a heads up what to > expect. > >>> >> Preferably I have materials for repair at hand and do not need to > leave the > >>> >> car ripped apart for too long, it is in a public location. > >>> >> I do have the service manual, but that just tells how to remove the > onboard > >>> >> chargers, not how to repair them, though I am comfortable > troubleshooting > >>> >> and soldering... > >>> >> Cor. > >>> >> -------------- next part -------------- > >>> >> An HTML attachment was scrubbed... > >>> >> URL: < > http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20240715/12915e2c/attachment.htm > > > >>> >> _______________________________________________ > >>> >> Address messages to ev@lists.evdl.org > >>> >> No other addresses in TO and CC fields > >>> >> HELP: http://www.evdl.org/help/ > >>> >> > _______________________________________________ > Address messages to ev@lists.evdl.org > No other addresses in TO and CC fields > HELP: http://www.evdl.org/help/ > > -------------- next part -------------- An HTML attachment was scrubbed... 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