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New PowerWall install woes

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I believe that the 60.5Hz cutoff is a requirement of the UL1741 standard, which I believe is required in all jurisdictions in the US now. So I suppose it doesn’t necessarily apply to all inverters as off grid inverters don’t need to conform to that standard and perhaps other countries have other requirements. But I believe that any grid connected inverter installed within at least the past couple of years will cut off at 60.5Hz. It is possible that I a mistaken about this though.

I decided to reply to this old thread since this information does not appear to be correct. The following is from Enphase ISO-NE 2018 profile:

FREQUENCY LIMITS
Over frequency disconnect Time Magnitude
Limit (fast) 160 ms 62.00 Hz
Limit (slow) 300,000 ms 61.20 Hz


Under frequency disconnect Time Magnitude
Limit (fast) 160 ms 56.50 Hz
Limit (slow) 300,000 ms 58.50 Hz

Reconnect frequency Magnitude
High 61.20 Hz

Low 58.50 Hz

RECONNECT
Start / Reconnect time 300 s
Anti-islanding reconnect time (long) 300 s

RAMP RATES
Soft-start ramp rate 2.00 %/s
 
OP here. Almost a year later and (hopefully) as a solution to the original issue, the 3rd-party installer has added a third PW. After much back-and-forth the first couple of months about the root cause and how to fix it, that was the solution they finally proposed and it's taken until now for them to get more PWs from Tesla.
 
OP here. Almost a year later and (hopefully) as a solution to the original issue, the 3rd-party installer has added a third PW. After much back-and-forth the first couple of months about the root cause and how to fix it, that was the solution they finally proposed and it's taken until now for them to get more PWs from Tesla.
Since I hear the max solar is 7.5kw per PW, seems you system may have not been designed correctly and should have had 3 PW's to start with?
 
Confused. I thought if batteries full, and GW ups the frequency to turn off the solar inverter?
Older inverters without partial curtailment are either on or off.
if you have 14 kW of PV and 10kW of ability to accept charge, the extra power has to go somewhere. If you arent using the excess every moment, then the GW will frequency shift to turn the inverters off. The issue is that there is never a condition when they can be on.

Batteries are full, customer uses 10% of them so they shift the frequency to allow PV production. PV production comes on and immediately overwhelms the batteries ability to charge. GW frequency shifts out of production range and the process goes on and on, inverter briefly kicking on then off. Only solution is to turn off some PV or increase load or add batteries.

Newer 1741 SA Inverters that are able to partially curtail the PV are ideal as they can throttle PV down to allow the batteries to charge.
 
OP here. Almost a year later and (hopefully) as a solution to the original issue, the 3rd-party installer has added a third PW. After much back-and-forth the first couple of months about the root cause and how to fix it, that was the solution they finally proposed and it's taken until now for them to get more PWs from Tesla.
Although it was great that installer put in another Powerwall, in approving it our utility told us we would not be able to sign up for ConnectedSolutions as the pole transformer that we paid for a year ago was now too small to handle the potential PV+PW output. Hate to pay for another one but it may just be worthwhile.
 
Although it was great that installer put in another Powerwall, in approving it our utility told us we would not be able to sign up for ConnectedSolutions as the pole transformer that we paid for a year ago was now too small to handle the potential PV+PW output. Hate to pay for another one but it may just be worthwhile.
I am not convinced that ConnectedSolutions is worth it. I keep calling Tesla asking if it is possible to view information about power provided to electric company during “the events” and nobody seems to know how it is all arranged. It feels like more of an experiment to figure out how to do it.
 
Although it was great that installer put in another Powerwall, in approving it our utility told us we would not be able to sign up for ConnectedSolutions as the pole transformer that we paid for a year ago was now too small to handle the potential PV+PW output. Hate to pay for another one but it may just be worthwhile.
I am not sure how your PV + PWs can exceed transformer rating. If supply line is 200A then the transformer is capable of that current in both directions. Each PW can feed up to 20A into the grid and 16KW AC PV maxes out at 66A (16K / 240) so combined amperage is way below 200.
 
Supposedly in NH one can sign up directly for ConnectedSolutions through utility without going through Tesla.

Utility is saying 17.5kW PV + 3x5kW PWs > 25kW transformer.
If your transformer is 25KW then the supply line is most likely 100A to match it. Most of the houses in my area have 200A/50KW service option so it is not an issue.
 
If your transformer is 25KW then the supply line is most likely 100A to match it. Most of the houses in my area have 200A/50KW service option so it is not an issue.
It's an issue when the utility says it's an issue. Currently moot as ConnectedSolutions is paused for state regulatory review in the coming weeks. Meanwhile, I'll just enjoy the third PW which should keep the whole system from shutting down when grid is out and solar produces > 10kW.
 
Although it was great that installer put in another Powerwall, in approving it our utility told us we would not be able to sign up for ConnectedSolutions as the pole transformer that we paid for a year ago was now too small to handle the potential PV+PW output. Hate to pay for another one but it may just be worthwhile.

I have given Connectedsolutions a try last year, and it was total failure. I had to opt out of the program before the end of the summer season.
The program claims that they do not use the batteries during severe weather conditions, but 2 times, my batteries were draining during a Storm Watch. I bought the powerwalls for backup, and last summer we were getting sudden severe thunderstorms on a weekly basis, and power was lost in other areas as a result. When I called Tesla customer support during the event, they could not figure out how to stop the Powerwalls. I had to shutdown my main breaker to stop battery from draining.

Eversource, my power utility, pushed the issue on Tesla. They said that they send the event the day before, and if the severe weather was not known, then it is up to Tesla Storm Watch to stop demand response from activating. But this setup was brittle as I have learned. Sometimes it doesn't work, and they don't have a way to stop it remotely.

Other issue with ConnectedSolutions was that the batteries were drained down to 20% every day from Monday-Friday during the summer days. Eversource told me that I can ask Tesla to set a different battery level, but Tesla never responded to my requests before I opted out of the program.

At this point, I would not consider joining the program unless
1) Tesla provides ability in app to set the battery reserve level for demand response events, and
2) Tesla provides ability to abort an event from the app (in case a severe storm is in the area and Storm Watch is not working).
 
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Other issue with ConnectedSolutions was that the batteries were drained down to 20% every day from Monday-Friday during the summer days. Eversource told me that I can ask Tesla to set a different battery level, but Tesla never responded to my requests before I opted out of the program.

At this point, I would not consider joining the program unless
1) Tesla provides ability in app to set the battery reserve level for demand response events, and
2) Tesla provides ability to abort an event from the app (in case a severe storm is in the area and Storm Watch is not working).
What did you have "Reserve for Power Outages" set to?