Growatt spf Not Seeing PV In The Morning

[Kornbread]

After finally getting an answer on safely wiring the Growatt spf6000t dvm-us to the grid, I was ready to finish installing this unit in the shop, and now a new issue arises. At 8am this morning, as most mornings, I was checking in with Solar Assistant and noticed no pv production. By 8am the system should be producing around ~1.5k. A quick trip to the shop confirmed no pv production and batteries at 54%. The solar panel icon on the Growatt lcd display was not lit. Pv voltage to the Growatt measured 97v. Cycled pv breakers. No change. Had to turn the Growatt off, wait for it to power down, and restart. Waited till it fully rebooted and turned on the pv breakers. It then recognized the pv input and began charging the batteries. This unit has been up and running 100% off grid since January with no issues ... other than questions caused by a severely lacking manual concerning wiring to the grid and n-g bonding. Nothing in the system has been changed, settings or otherwise.

My search'fu isn't that great as I found a few threads pertaining to the issue but no resolution.

 

[LydMekk]

Isn't 97V too low for the inverter to start? How many panels and how are they connected?
Could some panels have been disconnected so you only run on a few instead of all?
Just thinking out loud...

 

[Kornbread]

The panels are Trina with a Voc of 37.7v and Vmp of 30.5v connected three in series; 3s6p. The Growatt is the dvm-us model with an mppt operating voltage of 60-145v, max 150v. When generating max pv the mppt usually pulls the panels down to the high 70v to low 80v range. About the only thing I found on this forum searching, other than a wrong setting, was the unit was defective and had to be returned. I'll run through the settings once more, but it would be odd for a setting to somehow have changed.

 

[shopman]

I've had this happen two times with the 8kw version that I have. I contacted Signature Solar about the issue and was told that they see this happen when the PV input voltage is close to or exceeds the rated input voltage of the controller. Was it a partly cloudy morning where you live? The cloud lensing effect is real and can rapidly cause your PV panels to exceed Voc. I've rebooted the two times its happened and it goes back to running fine. There are never any faults or warnings on the display when this happens.

 

[Kornbread]

In the first clip, you can see where the unit was cycled at ~9:45am and pv generation began. In the second clip, you can see how it normally picks up. There were some clouds around noon in the first clip.

Here's the mppt voltage. No start on top and the normal early morning startup below. Voc approaching max does not appear to be an issue, which it should not as the Voc of the panels is 37.7v x 3 in series is only 113v, plus by 7am, it is already 80*f outside. Notice how the mppt plays around with loading. In the second clip, after 2pm the batteries were full, and other than covering loads, the mppt shut production down by placing the panels in a less efficient operating zone.

 

[shopman]

Very interesting. Everything on your end is well within operating parameters. I think I have a defective charge controller board in my unit. MPPT1 falls on its face for about an hour every morning. I have the MPV version of the inverter and run at around a measured Voc of 235v with two identical arrays, one on each MPPT. I've swapped the arrays to see if the problem followed the array, but it remains on MPPT1. The two times it failed to start both MPPT's I thought maybe I was pushing it a little too hard, but seeing as you're having the same issue, it appears there's a problem with the MPPT. Hoping that one of these days I have a day with no morning clouds, but living 3 miles from the ocean sometimes has its drawbacks. I'm going to pass this on to tech support and see what they come back with. Maybe its a calibration issue. Aside from this, its really a tank of an inverter that has elegantly handled everything that's been asked of it.

 

[Xhumeka]

This sounds pretty close to what this @rykelo describes in his post (very last post in this thread):

Growatt SPF 3000TL LVM Fault 08: High Bus Voltage

122 is the highest I have seen. Seems to be working fine now after some days, until today, that I decided to upgrade the firmware and it stopped at 50%, now it's dead! Any ideas how to get it back to original firmware or get the correct firmware version to flash it back? This is the same that...

diysolarforum.com

Watch his video ( https://photos.app.goo.gl/Ez75oFd71MBuo2kw9 ) - he has to power-cycle his unit just like you, except he has to do it multiple times per day.

As you have said, this seems to be a recurring problem for several people on this forum, hopefully Growatt can help correct this issue once and for all!

 

[Vigo]

Interesting problem.

I have a slightly different problem on an spf5000es where even when unit is 'off' it used to use solar to charge batteries when PV became available in the morning, but it has mysteriously stopped doing it and now has to be switched on to start utilizing pv for battery charging.

Watching this with interest..

 

[Kornbread]

Very interesting. Everything on your end is well within operating parameters. I think I have a defective charge controller board in my unit. MPPT1 falls on its face for about an hour every morning. I have the MPV version of the inverter and run at around a measured Voc of 235v with two identical arrays, one on each MPPT. I've swapped the arrays to see if the problem followed the array, but it remains on MPPT1. The two times it failed to start both MPPT's I thought maybe I was pushing it a little too hard, but seeing as you're having the same issue, it appears there's a problem with the MPPT. Hoping that one of these days I have a day with no morning clouds, but living 3 miles from the ocean sometimes has its drawbacks. I'm going to pass this on to tech support and see what they come back with. Maybe its a calibration issue. Aside from this, its really a tank of an inverter that has elegantly handled everything that's been asked of it. View attachment 104033

Interested in what you find out about the issue. Keep us posted.

 

[Kornbread]

This sounds pretty close to what this @rykelo describes in his post (very last post in this thread):

Growatt SPF 3000TL LVM Fault 08: High Bus Voltage

122 is the highest I have seen. Seems to be working fine now after some days, until today, that I decided to upgrade the firmware and it stopped at 50%, now it's dead! Any ideas how to get it back to original firmware or get the correct firmware version to flash it back? This is the same that...

diysolarforum.com

Watch his video ( https://photos.app.goo.gl/Ez75oFd71MBuo2kw9 ) - he has to power-cycle his unit just like you, except he has to do it multiple times per day.

As you have said, this seems to be a recurring problem for several people on this forum, hopefully Growatt can help correct this issue once and for all!

His/her issue appears to be during peak production. Mine just doesn't want to get out of bed in the mornings.

 

[Kornbread]

Interesting problem.

I have a slightly different problem on an spf5000es where even when unit is 'off' it used to use solar to charge batteries when PV became available in the morning, but it has mysteriously stopped doing it and now has to be switched on to start utilizing pv for battery charging.

Watching this with interest..

Mine used to function properly in power saver mode, but now the inverter portion runs normally as long as there is any pv, even 20w will keep it humming along. When pv finally equalls 0, the inverter does it cycle thing looking for a load. The first times this function was used, the inverter cycled looking for a load regardless of pv input.

 

[Zwy]

After finally getting an answer on safely wiring the Growatt spf6000t dvm-us to the grid, I was ready to finish installing this unit in the shop, and now a new issue arises. At 8am this morning, as most mornings, I was checking in with Solar Assistant and noticed no pv production. By 8am the system should be producing around ~1.5k. A quick trip to the shop confirmed no pv production and batteries at 54%. The solar panel icon on the Growatt lcd display was not lit. Pv voltage to the Growatt measured 97v. Cycled pv breakers. No change. Had to turn the Growatt off, wait for it to power down, and restart. Waited till it fully rebooted and turned on the pv breakers. It then recognized the pv input and began charging the batteries. This unit has been up and running 100% off grid since January with no issues ... other than questions caused by a severely lacking manual concerning wiring to the grid and n-g bonding. Nothing in the system has been changed, settings or otherwise.

My search'fu isn't that great as I found a few threads pertaining to the issue but no resolution.

Post up Bulk and Float settings..........

I'll wager Float is set way below Bulk. The GW and MPP do not allow PV charging until the float level is hit. If you set bulk at 57V and float at 54V, it will not charge until 54V is hit.

 

[Kornbread]

Post up Bulk and Float settings..........

I'll wager Float is set way below Bulk. The GW and MPP do not allow PV charging until the float level is hit. If you set bulk at 57V and float at 54V, it will not charge until 54V is hit.

The Growatt and eg4s talk to each other and work things out.

 

[Zwy]

The Growatt and eg4s talk to each other and work things out.

Doesn't sound like it.........

I'd be measuring with the voltmeter. I'm quite certain it is the Bulk/Float causing the problem.

On my GW 3000W, the dang thing kept powering up the SCC in low light conditions. Then came the annoying beep when it shut down as PV couldn't supply the load. I finally added a switch to turn PV off in low light conditions.

 

[Kornbread]

I think this is what @robby was referring to when talking about the eg4 LiFePower4 balancing act. State of charge 99%-100%, but yeah, I got no idea what eg4 and Growatt decided the values should be set. Not even sure which is the adult in the conversation. Does the Growatt, or eg4 bms call the shots?

 

[robby]

I don’t think it’s the same problem.
Your charging voltage is very high, your climbing the knees by going up to 57.6V. Your battery is trying to settle at 54.5V which is where I charge mine to. After a couple of hours that will drop to about 53.5V which is what I have found to be there 100% charge point if your staying off the knees and not stressing your battery. The gains of going higher are a minute or two of extra runtime and the downside is shortened battery life.

 

[Zwy]

I don’t think it’s the same problem.
Your charging voltage is very high, your climbing the knees by going up to 57.6V. Your battery is trying to settle at 54.5V which is where I charge mine to. After a couple of hours that will drop to about 53.5V which is what I have found to be there 100% charge point if your staying off the knees and not stressing your battery. The gains of going higher are a minute or two of extra runtime and the downside is shortened battery life.

I agree, it is a little high on bulk at almost 58V in that graph. How is Bulk and Float set with the EG4 and GW communication?

I prefer to just enter the start of the knee area so charging is high enough for BMS cell balancing.

 

[Vigo]

EG4 spec sheet


I'm certainly no expert but i assume one could be forgiven for not noticing a problem with charging to 58v when the spec sheet says 58v, at least until the forum educated me/us on the nuance/between the lines as to why we should charge to something lower?

It looks to me like the bms is either seeing the 60v cutoff and there is a voltage discrepancy somewhere, or one of the cells is hitting the 3.9v cutoff, and waiting until the bms balancing drops whichever back below the reconnect voltage, and then reconnects and accepts more charge? I mean, if the BMS is asking the Growatt for the same numbers written on the spec sheet, it's getting exactly what it asked for in the graph Kornbread shows.

 

[Kornbread]

xxxx

I don’t think it’s the same problem.
Your charging voltage is very high, your climbing the knees by going up to 57.6V. Your battery is trying to settle at 54.5V which is where I charge mine to. After a couple of hours that will drop to about 53.5V which is what I have found to be there 100% charge point if your staying off the knees and not stressing your battery. The gains of going higher are a minute or two of extra runtime and the downside is shortened battery life.

So you think this is just the battery settling? Will the eg4 software show its bms balancing the cells? Wonder if the laptop can be connected with the eg4 batteries while the Growatt remains active and connected?

 

[Kornbread]

I agree, it is a little high on bulk at almost 58V in that graph. How is Bulk and Float set with the EG4 and GW communication?

I prefer to just enter the start of the knee area so charging is high enough for BMS cell balancing.

That would be nice to know. This graph is with the unadulterated 'factory' settings when using communication between eg4 LiFePower4 batteries and a Growatt spfxxxxt aio. When communicating, which one is the master? Were these settings not agreed upon between the manufacturers as there had to be some cross-pollination for them to create, and then advertise this as a feature?

At what range does cell balancing occur with the LiFePower4?