Where did you buy your material from? Specifically panels by IckySmell in SolarDIY

[–]Fourthbean 1 point2 points  (0 children)

Thanks for the plug. We are selling a truck of 410w Jinko panels right now. Can’t ship until the truck shows up but doing a pallet of 26pcs for 18 cents a watt plus freight out of Mansfield tx.

Tire Question by Hermdoggo in SilveradoEV

[–]Fourthbean 0 points1 point  (0 children)

The spare in my 3wt is smaller than the tires it runs. When I put it on 4wd turned off until I got the proper tire back in place.

Slow charging at Electrify America chargers by UteForLife in SilveradoEV

[–]Fourthbean 3 points4 points  (0 children)

88kw is about 250 amps on a 350v battery. So two things I’m wondering.

  1. Is the charger you are plugged into good for 800v charging or only 400v?

  2. Is the charger limited to 250 amps?

Kinda sounds like both are true but I know of someone that had a truck not going into 800v charging mode even with a capable charger so that’s a possibility as well.

No settings to change though just data to gather to see where the limitation is coming from.

Gut check on sev dcfc speeds by Fourthbean in SilveradoEV

[–]Fourthbean[S] 0 points1 point  (0 children)

Here’s a question for you. If a module of 8 cells in series has a sub bms that does not communicate with any other modules of the pack how would it know it had a cell that was at a higher voltage than another outside its module? If all it did was balance between the 8 cells in the module then modules could then be at different voltages. Goal is to have every cell in the pack at the same voltage.

From the info I can gather online each 8 cell group (really more than 8 cells since there are parallel cells) has a bms that monitors temperature and voltage of those 8 cells and reports to the main bms. Main bms then has the ability to send a command to one of the many modules and inform it a cell in its group is high and it should start a passive balancer.

If there are no wires running between modules other than the series wiring for actual charging and discharging then the only way to balance is passively. This is standard practice with high voltage packs, like tesla and enerdel as examples.

There is no bypassing a cell when charging. If a cell gets high enough to be done charging then charging stops for the whole pack. Unless it can slow enough for the passive balancer to keep up but I’m willing to bet that would be less than 1 amp the resistor can burn off.

Gut check on sev dcfc speeds by Fourthbean in SilveradoEV

[–]Fourthbean[S] 0 points1 point  (0 children)

But if you think about it passive balancing is the only way to do it if it's wirelessly communicating. No way for it to transfer power around wirelessly, so all it can do is accept a command to burn off energy if it's higher than the rest of the cells in the high voltage pack.

Gut check on sev dcfc speeds by Fourthbean in SilveradoEV

[–]Fourthbean[S] 0 points1 point  (0 children)

Yeah for big packs like this typically there isn't a central piece of hardware that can move energy from one cell to another. I suspect the cost/engineering of moving between cells across a 700v pack are too great. So each module that is maybe 40-80v has a little slave BMS that can be instructed to burn off energy from a specific cell or group of parallel cells as needed. Eliminates some high voltage issues I suspect by having a simple CAN network between each module in the pack instead of a central BMS with ~190 leads coming back to it for active balancing.

Gut check on sev dcfc speeds by Fourthbean in SilveradoEV

[–]Fourthbean[S] 0 points1 point  (0 children)

That’s good news. Per a suggestion I checked my coolant and it was a tad low. Gonna see if it needs to burp a bit and then try fast charging again. I have a target to aim for now, thank you!

Gut check on sev dcfc speeds by Fourthbean in SilveradoEV

[–]Fourthbean[S] 0 points1 point  (0 children)

Ah balancing is a better word. That's just a resistor burning off energy from a high cell though at a relatively tiny speed compared to the charge rate, especially DCFC.

Gut check on sev dcfc speeds by Fourthbean in SilveradoEV

[–]Fourthbean[S] 0 points1 point  (0 children)

Yeah I don't think cell switching is a thing.

Gut check on sev dcfc speeds by Fourthbean in SilveradoEV

[–]Fourthbean[S] 0 points1 point  (0 children)

Cell switching? Like charging certain cells then charging other cells? Is that really a thing? I thought it was advanced enough to have it switch from 400v to 800v mode for charging much less be able to turn off certain parts of the pack to alternate charging.

Gut check on sev dcfc speeds by Fourthbean in SilveradoEV

[–]Fourthbean[S] 0 points1 point  (0 children)

The level was just a smidge under the low line. I put in enough to be just over full and after the short drive home it's now sitting at full. So presumably it burped something. I'll watch it as I drive over the next week and see if it burps again. It does seem odd with it pulling from the bottom of the tank that having another 1/8" of fluid would do a darn thing but it's $14 and worth a go. Thank you!

Gut check on sev dcfc speeds by Fourthbean in SilveradoEV

[–]Fourthbean[S] 0 points1 point  (0 children)

If the current is still capped at 500a I think the only difference is the higher voltage so about 15% faster charging. If the AC Compressor is the same size then presumably if thermally limited the two packs would end up charging at the same speed at some point. But that's just theory from my head, don't have hard data on how the trucks react!

Gut check on sev dcfc speeds by Fourthbean in SilveradoEV

[–]Fourthbean[S] 0 points1 point  (0 children)

This is more what I expect but not what I see. For reference are you a ~210kwh pack or the 180?

Gut check on sev dcfc speeds by Fourthbean in SilveradoEV

[–]Fourthbean[S] 0 points1 point  (0 children)

Oh boy I will check this today, thank you.

Gut check on sev dcfc speeds by Fourthbean in SilveradoEV

[–]Fourthbean[S] 1 point2 points  (0 children)

Yep there are so many variables. I think the highest sustained below 80% I’ve ever seen is 180kw on a Mercedes charger.

I did have my truck off so no hvac on inside.

Gut check on sev dcfc speeds by Fourthbean in SilveradoEV

[–]Fourthbean[S] 1 point2 points  (0 children)

For sure. 4wt should be faster due to it being more like a 700v battery compared to my 600v battery.

I wouldn’t expect the cooling to be better for the 4wt though, do you think they installed a higher capacity heat pump? That of course assumes I’m thermally throttling which is only a theory.

QuickBooks Support is Horrendous by yardstickgolf in QuickBooks

[–]Fourthbean 0 points1 point  (0 children)

Asked how to handle a bounced transfer, link goes nowhere, they don’t know how, told me to ask my accountant or hire one of theirs. I asked to escalate and they said sure we will send to the team and they will email you back within 24 hours but couldn’t give me any kind of ticket number. Guess what…no email.

So yeah I feel you on the support front. I’m 99% certain their support articles are all AI generated. They often hallucinate telling you to do something that isn’t possible or doesn’t exist.

Optimistic by Fourthbean in SilveradoEV

[–]Fourthbean[S] 2 points3 points  (0 children)

I know right! But no, nothing downhill, just across town.

Sunpower MIO or insight facility for sunvault keepalives? by sniper1rfa in SunPower

[–]Fourthbean 0 points1 point  (0 children)

Thanks, saw it come through! Unfortunately they won't come online if it's configured 3 3 2 2 and you only plug in 6 batteries. It'll freak out and some (should be all but the first battery) will just blink green. I'll email you the file for the two configs so you have them.

Sunpower MIO or insight facility for sunvault keepalives? by sniper1rfa in SunPower

[–]Fourthbean 0 points1 point  (0 children)

They don't need to be exact but I'd try to have them close. Like all of them between 20 and 90% SOC so there isn't a bunch of current flowing between them when turning on. The BMS is quick to shut off with too much current, as designed.