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Very low production 7.6 system with powerwall +- is inverter configured right?

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My 7.6KW system got installed a week ago i am still waiting PTO. System in full sun will max at 2.8KW. i have two strings coming from the roof one independent for 3 panels facing east with shade to mppt 1, and 16 panels in a combined string facing east no shade mppt 4 jumber with 3. System performance is horrible at 2.8. contacted tesla they said you are still in pto and power is reduced. I am not sure this is the case since my battery is not full! Attached image of my wiring and production
 

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Doing the math with 400 watt panels generating max 37V in optimal conditions…

String 1 is 3 panels x 37 watts = 111V which is actually lower than what you’re getting.
String 3/4 is 2 sets of 8 panels in series and then combined. Each string should be 8 x 37V = 296V which is close to what you’re getting. It’s producing almost 8A total now, and ideally will make 21A unthrottled.

There is only one pair of output wires from the inverter, and the CT reading on it matches the inverter reading.

So looks ok. Gotta wait til after PTO to see if unthrottled system produces what it should.
 
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Doing the math with 400 watt panels generating max 37V in optimal conditions…

String 1 is 3 panels x 37 watts = 111V which is actually lower than what you’re getting.
String 3/4 is 2 sets of 8 panels in series and then combined. Each string should be 8 x 37V = 296V which is close to what you’re getting. It’s producing almost 8A total now, and ideally will make 21A unthrottled.

There is only one pair of output wires from the inverter, and the CT reading on it matches the inverter reading.

So looks ok. Gotta wait til after PTO to see if unthrottled system produces what it should.
Thanks for your detailed answer. I hoping this is the case، as i read conflicting information about u throttling, some said it happens only when battery is full other said happens all the time under PTO, I wish if Tesla give clear documentation about unthrottling. If you don't mind can you explain how did you come up with the 21A? (I am really wishing for that). Thanks
 
Thanks for your detailed answer. I hoping this is the case، as i read conflicting information about u throttling, some said it happens only when battery is full other said happens all the time under PTO, I wish if Tesla give clear documentation about unthrottling. If you don't mind can you explain how did you come up with the 21A? (I am really wishing for that). Thanks
I wouldn't think there would be throttling at ~50% SOC. String 1 isn't really producing anything when you took the screenshot. Was it heavily shaded at that time? String 2/3 seems to be producing lower current than I would expect for 10AM on an East facing array. Was this with full sun? What latitude are you at?
 
If one of the pairs of combined 8 panel strings is not connected, you'll see same voltage but half the expected amps. 8A at peak sun unthrottled at this time of the year may indicate one string is disconnected and thus you're seeing half of the expected production. But you can't determine that til after PTO when there's no more throttling.
 
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I wouldn't think there would be throttling at ~50% SOC. String 1 isn't really producing anything when you took the screenshot. Was it heavily shaded at that time? String 2/3 seems to be producing lower current than I would expect for 10AM on an East facing array. Was this with full sun? What latitude are you at?
Yes string 1 was fully shaded. String 2 was full sun. I am in NJ
 
Just to be fully clear, OP, I am not saying that "you have no issue" (cause I dont know that at all). Im just saying that, if you have a powerwall+, tesla sets up some sort of non export settings on the PV system, so its hard to even evaluate it fully until you get PTO. I dont know all the circumstances that it throttles, to what extent, etc.

I do think, however, that tesla wont be willing to even look at it until you have PTO unless its obviously wrong... and they are not going to go on a weeks worth of data to determine that its wrong.

You might need to just keep an eye on it, document everything, then pounce on them once you get PTO.
 
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Just to be fully clear, OP, I am not saying that "you have no issue" (cause I dont know that at all). Im just saying that, if you have a powerwall+, tesla sets up some sort of non export settings on the PV system, so its hard to even evaluate it fully until you get PTO. I dont know all the circumstances that it throttles, to what extent, etc.

I do think, however, that tesla wont be willing to even look at it until you have PTO unless its obviously wrong... and they are not going to go on a weeks worth of data to determine that its wrong.

You might need to just keep an eye on it, document everything, then pounce on them once you get PTO.
Thanks, and I agree with you. I just sent them an email I am sure I am going to get the same response "you are still in PTO". I will keep taking snapshots untill pto.
 
Thanks, and I agree with you. I just sent them an email I am sure I am going to get the same response "you are still in PTO". I will keep taking snapshots untill pto.

I saw no output reduction pre-PTO unless my batteries were at 100%, then it cuts production as there's no where to send the electricity. Unless those walls are at 100%, there should be no throttling.

TIm
 
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I do not understand why folks ask questions pre-pto when technically, system should not even be turned on
PTO only applies to sending power to the grid, not self use, as they need to have an account of exports in order to better manage the grid and localized current to transformers. If everyone turned on their devices to export to the grid this could create problems (particularly locally) with overload on transformers.

Minus contractual agreements from installers, there are no restrictions from the utility company to turning on your system for your own self use; just as you can connect a generator and transfer switch to use it any time without permission from the utility (just local municipality permits if required in your area.)
 
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PTO only applies to sending power to the grid, not self use, as they need to have an account of exports in order to better manage the grid and localized current to transformers. If everyone turned on their devices to export to the grid this could create problems (particularly locally) with overload on transformers.

Minus contractual agreements from installers, there are no restrictions from the utility company to turning on your system for your own self use; just as you can connect a generator and transfer switch to use it any time without permission from the utility (just local municipality permits if required in your area.)
I am not aware of most systems that are turned on cannot send back to the grid, unless the main breaker is turned off? I am not aware of folks doing this.
So, one can play with words all one wants, bottom line from what the wording said to me from PGE, until PTO, it cannot be turned on, period. So does not matter who turned on or left one, techincally it cannot be one. But the chances of an issues are small, but not zero.
I know before PTO, yep, my installer left on. There was NO way to stop from sending excess back to the grid, I just got zero credit for it.
 
I am not aware of most systems that are turned on cannot send back to the grid, unless the main breaker is turned off? I am not aware of folks doing this.
Yep. Tesla Solar Gateway can control export to the grid with a software setting. Once PTO is received, Tesla remotes into the system and enables it. This allows the system to operate in self-usage mode upon install.

So, one can play with words all one wants, bottom line from what the wording said to me from PGE, until PTO, it cannot be turned on, period.
I don't give a hoot about PGE or any silly California laws. I live in Texas. Not sure where OP is, but likely doesn't give a hoot either.

So does not matter who turned on or left one, techincally it cannot be one. But the chances of an issues are small, but not zero.
I know before PTO, yep, my installer left on. There was NO way to stop from sending excess back to the grid, I just got zero credit for it.
Incorrect, see point above on Tesla Solar Gateway. I'm sure there's folks smarter than I on here who can elaborate, but you might want to learn abuut the new Gateway 2.0 which has the capability to software inhibit export.
 
Yep. Tesla Solar Gateway can control export to the grid with a software setting. Once PTO is received, Tesla remotes into the system and enables it. This allows the system to operate in self-usage mode upon install.


I don't give a hoot about PGE or any silly California laws. I live in Texas. Not sure where OP is, but likely doesn't give a hoot either.


Incorrect, see point above on Tesla Solar Gateway. I'm sure there's folks smarter than I on here who can elaborate, but you might want to learn abuut the new Gateway 2.0 which has the capability to software inhibit export.
to each their own
 
I am not aware of most systems that are turned on cannot send back to the grid, unless the main breaker is turned off? I am not aware of folks doing this.
So, one can play with words all one wants, bottom line from what the wording said to me from PGE, until PTO, it cannot be turned on, period. So does not matter who turned on or left one, techincally it cannot be one. But the chances of an issues are small, but not zero.
I know before PTO, yep, my installer left on. There was NO way to stop from sending excess back to the grid, I just got zero credit for it.

I understand what you are attempting to say here, but there are many instances (Tesla installs, with powerwall + systems are one), where tesla can configure the system in a "non export" mode. In this mode (if equipment supported / enabled) a person can operate their system without exporting anything at all to the utility.

The utility agreements are "dont export anything" they arent "dont use". Not all systems qualify for setting up this non export settings, so there is no blanket statement that can be made on whether a person will or wont have this available, but if they do, there isnt any issue with them using it this way.

The only real issue is, since the system will curtail production in some manner when the batteries get full, the system will not operate in the same manner post PTO as pre PTO, and it can be confusing for some.
 
My question now, what is the most effective way to get Tesla agree to come back and re-inspect their installation. Since i am now almost sure there is an issue and the system is slmost running at 50% capacity. Examples of full sunny days of my 7.6 system.
 

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