What will powerwalls charge up to before excess dumped to grid?

[MXDogCrate]

Interesting conversation. FWIW, our PW Electrician said 0% is really 20%.

 

[sorka]

Has anyone done a PW disassembly to determine the true cell count and capacity? Are there an hidden diagnostic menus that would show cell voltage along with SOC? 4.2 volts is a true 100% charge.

 

[sorka]

Did you get Tesla to set your Gateway to only rise to 60.5 Hz? They lowered mine to 62.5 Hz but did not want to go lower. As I read the specs on my Delta M inverters is shows they provide 59.5 to 60.5 Hz, so I am not sure why Tesla would not go lower. Maybe being conservative with the inverter's exact frequency cut off?

I tested this today. At 97% off grid I was still seeing 59.9 Hz. At low 98%, it rose to 60.2. Midway through 98% it hit 60.5 and the inverter shut off. At this point I did a full Insteon device status query. Two devices failed to respond (including retries). The fact that most of the devices still talk ok is almost certainly because most of them are dual mode Insteon and also use wireless as a redundancy. So all in all even if I'm off grid with a full charge, not a big deal.

 

[jboy210]

I tested this today. At 97% off grid I was still seeing 59.9 Hz. At low 98%, it rose to 60.2. Midway through 98% it hit 60.5 and the inverter shut off. At this point I did a full Insteon device status query. Two devices failed to respond (including retries). The fact that most of the devices still talk ok is almost certainly because most of them are dual mode Insteon and also use wireless as a redundancy. So all in all even if I'm off grid with a full charge, not a big deal.

Glad it is working out for you.

 

[aesculus]

So all in all even if I'm off grid with a full charge, not a big deal.

I agree. The so few times this is going to happen it's just not worth any more effort. Heck for me those Insteon devices are less reliable in general than this occasional use case.