What to expect after commissioning, but before PTO

[jboy210]

The system is being installed with roof and 2 powerwalls. What will and will not work after the install is finished and before PTO from PG&E. That is:

• Will the roof be producing power?
• Will the powerwalls get charged from the solar production?
• Would the gateway cutover to the powerwalls in an outage?
  
• Can I see any outputs from the Tesla app?
• Can I access gateway in my network from an application I write?

 

[bob_p]

I'm in Houston - so have a different utility, but would expect the results to be similar.

Before PTO, after the system is installed, the Tesla Gateway will be running, but the PowerWalls and solar panels will not be operating.

Our utility requires a large "generation disconnect" switch located near the electricity meter. Except for testing of the system, the disconnect switch is supposed to be in the "off" position, which disconnects the PowerWalls and the solar panels from the Tesla Gateway. This is to ensure the system has been reviewed by the utility before the PowerWalls and solar panels (which provide power) are connected to the grid.

Because the grid power goes through the Tesla Gateway to the house, there isn't any way to remove it from the grid to house circuit, so the Gateway will be running, but will likely be in the "system off" mode (since it has nothing to do until the solar panels and PowerWalls are connected.

While waiting for PTO, I did run some limited duration tests, putting the generation disconnect switch in the ON position so that I could verify the PowerWalls, solar panels, microinverters and Tesla Gateway were all operating as expected. Because if there was a problem, I wanted to get it fixed while we were waiting for PTO. But once those tests were finished, I disconnected the PowerWalls (each also has an on/off switch) and solar panels and put the Gateway back in "system off" model, because if the utility found we were using the system before PTO, that could make it difficult to get PTO.

During the limited testing, if there is sun and/or the PowerWalls have some energy stored, you can perform a quick "off grid" test by throwing the breaker in the Tesla Gateway panel. This will disconnect the grid power and verify the Gateway properly transitions to PowerWall/solar power - and that you don't have any problems with devices in your house. Once you've done that, you can reset the breaker in the Gateway panel and once the system transitions back to grid power (which could take 5-10 minutes), you can again do the generation disconnect and put the Gateway in off mode.

One thing you can't test until you have PTO is the powerline/solar cutoff frequency the Gateway uses when the PowerWalls are fully charged and you go off-grid while the solar panels are generating power. When you're off grid and the PowerWalls are full, there is no where for the solar energy to go - so the Gateway sets the powerline frequency high to shut down the solar inverter/microinverters. Tesla has been using 65Hz as the default frequency - which causes problems with some devices inside the house (UPS, refrigerators, air conditioners, pool pumps). If you experience any problems, request that your installer or Tesla lower the solar cutoff frequency (probably to 61 or 61.5Hz), whatever is needed to turn off your inverters/microinverters.

 

[jboy210]

I'm in Houston - so have a different utility, but would expect the results to be similar.

Before PTO, after the system is installed, the Tesla Gateway will be running, but the PowerWalls and solar panels will not be operating.

Our utility requires a large "generation disconnect" switch located near the electricity meter. Except for testing of the system, the disconnect switch is supposed to be in the "off" position, which disconnects the PowerWalls and the solar panels from the Tesla Gateway. This is to ensure the system has been reviewed by the utility before the PowerWalls and solar panels (which provide power) are connected to the grid.

Because the grid power goes through the Tesla Gateway to the house, there isn't any way to remove it from the grid to house circuit, so the Gateway will be running, but will likely be in the "system off" mode (since it has nothing to do until the solar panels and PowerWalls are connected.

While waiting for PTO, I did run some limited duration tests, putting the generation disconnect switch in the ON position so that I could verify the PowerWalls, solar panels, microinverters and Tesla Gateway were all operating as expected. Because if there was a problem, I wanted to get it fixed while we were waiting for PTO. But once those tests were finished, I disconnected the PowerWalls (each also has an on/off switch) and solar panels and put the Gateway back in "system off" model, because if the utility found we were using the system before PTO, that could make it difficult to get PTO.

During the limited testing, if there is sun and/or the PowerWalls have some energy stored, you can perform a quick "off grid" test by throwing the breaker in the Tesla Gateway panel. This will disconnect the grid power and verify the Gateway properly transitions to PowerWall/solar power - and that you don't have any problems with devices in your house. Once you've done that, you can reset the breaker in the Gateway panel and once the system transitions back to grid power (which could take 5-10 minutes), you can again do the generation disconnect and put the Gateway in off mode.

One thing you can't test until you have PTO is the powerline/solar cutoff frequency the Gateway uses when the PowerWalls are fully charged and you go off-grid while the solar panels are generating power. When you're off grid and the PowerWalls are full, there is no where for the solar energy to go - so the Gateway sets the powerline frequency high to shut down the solar inverter/microinverters. Tesla has been using 65Hz as the default frequency - which causes problems with some devices inside the house (UPS, refrigerators, air conditioners, pool pumps). If you experience any problems, request that your installer or Tesla lower the solar cutoff frequency (probably to 61 or 61.5Hz), whatever is needed to turn off your inverters/microinverters.

Thanks. I want to run testing to verify this all works for the same reason you suggest, getting Tesla to fix it early.

During a limited testing how do you verity the transition of Powerwall to solar power and charging of Powerwall from solar? Would the app be up and getting data from the gateway, and thus be showing power flows and battery state? If so, is that sufficient to verify the CTs and other probes are connected correctly? Or are there parts of the gateway not working in this state.

On the frequency I am going have Tesla set them as low as they can. We have a number of USPs units and they support 60Hz +/- 3 Hz.

 

[CA-Gbm84]

Powerwall installers should demonstrate a backup test for you at the end of commissioning by flipping your main breaker. This includes the power flows in the app - that should work at the time of commissioning.

Local API access will be available as soon as the gateway is connected to your network and commissioning is finished.

Technically the PV should not be on at all until PTO - but many installers will turn it on briefly to show you it has all been commissioned correctly. This is generally fine, even more so if you are doing it during the back test of the powerwalls as you are islanded from the grid.

Installers will not have access to frequency settings, that needs to be done by technical support. They generally will not make any adjustments until there is enough data to show the PV inverters are curtailing/tripping correctly at roughly +2 Hz, otherwise that will risk damage to Powerwall and other devices in your home. So you may need to wait a few days/weeks to get that data. You can force it by setting PW to charge fully and then doing a backup test by flipping main breaker while PV is producing.

 

[jjrandorin]

Thanks. I want to run testing to verify this all works for the same reason you suggest, getting Tesla to fix it early.

During a limited testing how do you verity the transition of Powerwall to solar power and charging of Powerwall from solar? Would the app be up and getting data from the gateway, and thus be showing power flows and battery state? If so, is that sufficient to verify the CTs and other probes are connected correctly? Or are there parts of the gateway not working in this state.

On the frequency I am going have Tesla set them as low as they can. We have a number of USPs units and they support 60Hz +/- 3 Hz.

I doubt you are going to get tesla to change the frequency before PTO, but you can certainly try. Since tesla is installing your roof, they will likely setup the app so you will see all the flows properly. They should also flip your main breaker to test whether the system is functioning.

You wont be able to test the frequency issue because the batteries wont be full at that time. You can likely run the system enough to charge the batteries to full, but then I would turn it off since you wont have PTO. I would turn it on if the powerwalls get below 10% to charge them back up, but I personally wouldnt leave the system on "testing" it before you get PTO as you dont want to risk PGE delaying you, etc.

For practical purposes, if you are not exporting to the grid, they wont really be able to tell... but will you be able to consume 100% of the solar you are generating in the middle of the day?

 

[jrweiss98020]

My system was fully functional after commissioning, except that the PV was switched off. I disconnected from the grid with the breaker at the Gateway, and turned on the PV. I ran the house for 2 days like that (PV + PW) until SnoPUD came for the PTO. I disconnected the PV and reconnected to the grid before the inspector showed up.

 

[Benng]

My system was fully functional after commissioning, except that the PV was switched off. I disconnected from the grid with the breaker at the Gateway, and turned on the PV. I ran the house for 2 days like that (PV + PW) until SnoPUD came for the PTO. I disconnected the PV and reconnected to the grid before the inspector showed up.

By disconnecting yourself with grid, they don’t know if your system is running right? As long as you’re not upstreaming anything I think you’ll be fine. Did you continue to run your system until you receive PTO?

 

[BrettS]

By disconnecting yourself with grid, they don’t know if your system is running right? As long as you’re not upstreaming anything I think you’ll be fine. Did you continue to run your system until you receive PTO?

For me, the line is feeding power back to the grid. The chance is minuscule, but theoretically if something went wrong with your system and caused a problem with the grid because it was feeding power into it, or even if something happened and a lineman or someone got hurt and it came out that you were operating your system and feeding back to the grid before PTO then that could be bad. Again, I think the chances of that happening are minuscule, but I see it more as permission to interact with the grid and feed power back to the grid. If you don’t have permission to do that then you shouldn’t be doing it.

However, as far as them knowing that your system is running, they can probably still tell by your usage. In my case I went from consistently using 2500-3000kWh per month to using just over 400kWh in July. Right now it’s looking like I’ll be under 200kWh from the grid in August, so obviously a change like that would be noticeable if anyone looked, but I suspect that no one would really be looking. And even if they did look I don’t think there’s really much they could complain about since my system is disconnected from the grid, so it’s not interacting with the grid and any problems with my system couldn’t cause any problems for the grid.

If you’re talking about disconnecting from the grid for a few hours just to do a little test here or there, then that would be much less likely to be noticeable and it wouldn’t make a significant impact on your monthly usage. If you have a smart meter that measures your usage in 15 or 60 minute intervals, then someone who was really digging could probably find a period of a few hours where your house was drawing no power, but again, I can’t imagine that anyone would do that or would even care.

 

[jrweiss98020]

By disconnecting yourself with grid, they don’t know if your system is running right? As long as you’re not upstreaming anything I think you’ll be fine. Did you continue to run your system until you receive PTO?

Yes. It only took 2 days for the inspector to come out and give the PTO.

[QUOTE}For me, the line is feeding power back to the grid. The chance is minuscule, but theoretically if something went wrong with your system and caused a problem with the grid because it was feeding power into it, or even if something happened and a lineman or someone got hurt and it came out that you were operating your system and feeding back to the grid before PTO then that could be bad.[/QUOTE]
That's why I opened the main breaker between the PV+PW system and the grid. There was no possibility of feedback.

 

[SMAlset]

A bit different situation here. We’re installed but not commission yet. Next scheduled appointment isn’t until 15th when they have some maintenance issues on their checklist along with commissioning to complete. Our black Gateway is connected and my husband has the app portion working on his phone. When the PW team left, the 3 PWs were showing 27% charge. As of tonight it’s down in the teens. Are we suppose to turn the power switches on the PWs to the off position until they come out?

 

[BrettS]

A bit different situation here. We’re installed but not commission yet. Next scheduled appointment isn’t until 15th when they have some maintenance issues on their checklist along with commissioning to complete. Our black Gateway is connected and my husband has the app portion working on his phone. When the PW team left, the 3 PWs were showing 27% charge. As of tonight it’s down in the teens. Are we suppose to turn the power switches on the PWs to the off position until they come out?

If you can see the system in your app and the battery level of the powerwalls then your system has been commissioned. At least the gateway and powerwall portion has been. It’s possible that your inverter hasn’t been commissioned yet.

As far as turning off the powerwalls, it might not be a bad idea and may help stop them from draining further. If you do wind up in a stormwatch alert then you could turn them back on again and they should charge from the grid.

 

[SMAlset]

If you can see the system in your app and the battery level of the powerwalls then your system has been commissioned. At least the gateway and powerwall portion has been. It’s possible that your inverter hasn’t been commissioned yet.

As far as turning off the powerwalls, it might not be a bad idea and may help stop them from draining further. If you do wind up in a stormwatch alert then you could turn them back on again and they should charge from the grid.

Our PW installer said he doesn’t usually set up the SolarEdge (our Solar installer team finished the roof the day before) but he said he has done it a few times and he tried for a while on his phone to get it to connect but I don’t think he thought it was successful in the end. I recall him saying someone would be out to commission it so I think you are right only part of the system got set up.

Are we allowed to charge the PWs from the grid at this point? It’s likely a StormWatch will get generated considering the upcoming weather. Also noticed the smoke now website is showing a new GPS satellite spotted fire has broken out in Coe (SCU Complex, only one earlier today) so that is a bit troublesome as well.

 

[BrettS]

Are we allowed to charge the PWs from the grid at this point? It’s likely a StormWatch will get generated considering the upcoming weather. Also noticed the smoke now website is showing a new GPS satellite spotted fire has broken out in Coe (SCU Complex, only one earlier today) do that is a bit troublesome as well

I would think that’s fine. It sounds like your powerwalls are commissioned and powered on and as long as you enable stormwatch should charge from the grid if a stormwatch is called. My installers left my powerwalls turned on and enabled when they left and it sounds like yours did as well.

I seem to recall that for some reason it took a couple of days before the stormwatch option appeared in my app though, so if you don’t see it there now check again over the next few days and it should appear.

 

[SMAlset]

We checked app and Stormwatch is activated, so batteries will be charging overnight then I assume? We’re in Block 50 so don’t expect to lose power. Since we don’t have PTO though, and won’t for some time since they still have things to do here before inspection, will the house only pull energy from the PWs if we lose power and in which case won’t PG&E have a problem with that at this point in time? As you can tell only beginning to learn how the system operates.

Thanks for the replies BTW. No one in Tesla offices now to ask.

 

[BrettS]

We checked app and Stormwatch is activated, so batteries will be charging overnight then I assume? We’re in Block 50 so don’t expect to lose power. Since we don’t have PTO though, and won’t for some time since they still have things to do here before inspection, will the house only pull energy from the PWs if we lose power and in which case won’t PG&E have a problem with that at this point in time? As you can tell only beginning to learn how the system operates.

Thanks for the replies BTW. No one in Tesla offices now to ask.

First make sure that stormwatch is actually active. If you look in the settings you can turn stormwatch on or off, but if it’s on there that just means that when tesla issues a stormwatch your powerwalls will respond to it. Even when there’s not an active stormwatch there’s a lot of animation and it looks like things are happening, but it just says “standby” under stormwatch in the settings.

Once tesla issues a stormwatch for your area (and you have it turned on in settings) then it should start charging from the grid immediately and it should say “stormwatch” on the main screen.

Either way, the powerwalls should take over if the power fails. You can always try to turn off your service disconnect to verify.

 

[SMAlset]

Thanks again! Our stormwatch setting is on and see it’s on Standby on the screen so guessing we haven’t had it issued for our area, at least not yet. And yes just the animation going, nothing to PWs overnight. They're at 17%.

Checked out a couple of the app screens and saw the two power interruptions that occurred on the 2nd when our installer turned off the power to show my husband how it responded when power would be lost.

Fun new toy to play around with. Nice app interface. This morning watched how it responded to our A/C unit kicking in (no Sure Start yet on it) and when I charged my car. We went around the house turning off some items and interesting to see what the reading would be.

 

[LadyLion]

I would think that’s fine. It sounds like your powerwalls are commissioned and powered on. My installers left my powerwalls turned on and enabled when they left and it sounds like yours did as well.

My installers finished on Friday afternoon, a large system with 3 PWs. They left the PVs on and the custom setting on self powered with PWs set at 100%. When100% was reached the excess solar power is going to the grid. We did move the 100% down to 50% but the PWs charged back up to 100% and power was sent to home and excess to grid starting at noon.
The installers told us to leave the inverter turned to the on setting. They said the inspector may turn the inverter to off. They did not show us any switch to stop power from going to/from the grid.
We are awaiting a modification to our permit (they moved some panels to aggregate on two roofs, not three) and for inspection after. Then PTO. Unknown how long this will take. Should we try to turn off power to the grid? How do you do that?
If we leave the PWs at 100% we overproduce solar energy during the day by about 11-15 kWh or more (my guess from studying the power flows over Sat, Sun, and today) and it shows the excess flowing to the grid. We used only 1.2kwh from the grid today. Our PW is 85% at 8:30 pm. Overnight It will probably go to 55% before the PVs start generating enough to power the home tomorrow morning. We are basically able to not use our utility company/grid at all in this weather that we are enjoying now.
@jrweiss98020

 

[jjrandorin]

My installers finished on Friday afternoon, a large system with 3 PWs. They left the PVs on and the custom setting on self powered with PWs set at 100%. After this 100% was reached the excess solar power is going to the grid. We did move the 100% down to 50% but they charged back up to 100% and power was sent to the grid. The installers told us to leave the inverter turned to the on setting. They said the inspector may turn the inverter to off. They did not show us any switch to stop power from going to the grid. We are awaiting a modification to our permit (they moved some panels to aggregate on two roofs, not three) and inspection after. Then PTO. Unknown how long this will take. Should we try to turn off power to the grid? How do you do that?
If we leave the PWs at 100% we overproduce solar energy during the day by about 11-20 kWh or more (my guess from studying the power flows over Sat, Sun, and today) and it shows the flow going to the grid.

There isnt a setting in the app to stop the power from going to the grid. In order to stop that, you have to shut the inverters off. I am surprised they told you to leave the inverters in the On position, when you dont have Permission to operate.

The other way you could stop power from going to the grid would be turn the main breaker to your home in the OFF position, but if you are one to do that, you would likely already be doing it (lol).

If both your solar and powerwalls are new, I question the installers direction to LEAVE them in the on position. I get them telling you to let the powerwalls charge up, but at that point they should likely be in the OFF position so that you dont generate solar without permission to operate (PTO).

 

[BrettS]

My installers finished on Friday afternoon, a large system with 3 PWs. They left the PVs on and the custom setting on self powered with PWs set at 100%. After this 100% was reached the excess solar power is going to the grid. We did move the 100% down to 50% but they charged back up to 100% and power was sent to the grid. The installers told us to leave the inverter turned to the on setting. They said the inspector may turn the inverter to off. They did not show us any switch to stop power from going to the grid. We are awaiting a modification to our permit (they moved some panels to aggregate on two roofs, not three) and inspection after. Then PTO. Unknown how long this will take. Should we try to turn off power to the grid? How do you do that?
If we leave the PWs at 100% we overproduce solar energy during the day by about 11-20 kWh or more (my guess from studying the power flows over Sat, Sun, and today) and it shows the flow going to the grid.

It definitely seems odd for your installers to leave your system on before you have PTO. You have two options to avoid sending power back to the grid. You could go off grid by turning off your service disconnect. This will allow your house to run on solar and your powerwalls. If you have any non backed up loads they will not function, and you will probably want to pay close attention to make sure that your powerwalls have enough power for you to make it through the night and make sure that you are generating enough solar power to recharge the powerwalls during the day.

If you aren’t feeling so adventurous then the other option is to just turn off your inverters so you aren’t generating solar power at all. There is no way to stay on the grid, leave leave the inverters on and not send excess power to the grid. Your utility expects your inverters to be off until you get PTO.

 

[jboy210]

My installers finished on Friday afternoon, a large system with 3 PWs. They left the PVs on and the custom setting on self powered with PWs set at 100%. When100% was reached the excess solar power is going to the grid. We did move the 100% down to 50% but the PWs charged back up to 100% and power was sent to home and excess to grid starting at noon.
The installers told us to leave the inverter turned to the on setting. They said the inspector may turn the inverter to off. They did not show us any switch to stop power from going to/from the grid.
We are awaiting a modification to our permit (they moved some panels to aggregate on two roofs, not three) and for inspection after. Then PTO. Unknown how long this will take. Should we try to turn off power to the grid? How do you do that?
If we leave the PWs at 100% we overproduce solar energy during the day by about 11-15 kWh or more (my guess from studying the power flows over Sat, Sun, and today) and it shows the excess flowing to the grid. We used only 1.2kwh from the grid today. Our PW is 85% at 8:30 pm. Overnight It will probably go to 55% before the PVs start generating enough to power the home tomorrow morning. We are basically able to not use our utility company/grid at all in this weather that we are enjoying now.
@jrweiss98020

Our installers did the same thing. They left it on and went about their site cleanup and then left. I had a couple of questions the next day, and when I called I mentioned the system was on. The response was a underwhelming, "Ok. You should probably turn it off".