Growatt SPF 3000TL LVM-24P - Bypass Error Issue

[Off Gridin' It]

I have been having an issue with the Bypass function on my Growatt SPF 3000TL LVM-24P Inverter.

I have provided a link to the videos showing the errors and settings. One is the error itself and one is a vid of the settings.
Please take a look and help me solve this problem.

I have tried a lot of different settings and this error still occurs even with the AC Distribution panel breaker disconnected.
All connections are solid and gas tight.

I am working with Signature Solar on the problem and they escalated the call to the higher ups but so far they have not gotten back to me.

This is installed in a 30 amp camper.
2013 Coachman apex 278rls - 30 feet

It is in the United States so our voltages here are 120 volts.
Thanks!
https://www.dropbox.com/sh/e3jll87u7nu11a3/AAAvzrlPIl-emjPSL3nC2GC4a?dl=0
Link to Error video and settings

 

[Mattb4]

My data amounts are limited (I am just about used up for the month) so I generally will not watch videos. Perhaps you would describe the Bypass error you are getting.

 

[Off Gridin' It]

My data amounts are limited (I am just about used up for the month) so I generally will not watch videos. Perhaps you would describe the Bypass error you are getting.

Basically if the inverter is in the on position. (The switch at the bottom) it functions perfectly. However, if you flip the switch into the "Off" position to put it into bypass mode it will go through a cycle through sort of a restart every 50 seconds. You will hear the fan kick on then the screen go blank for a millisecond and all three lights blink for another millisecond then the whole screen comes on showing all options then it starts back up again. This all happens in about a second.

No error codes are displayed. no loads on the inverter.
How it should be functioning in bypass it that basically the inverter is off and it won't output any 120 volts AC. But the MPPT charge controller will work and still charge the batteries from Solar. Bypass needs to be able to work so the standby consumption is can be reduced when the AC power is not needed. (Typically at night while sleeping)

This error will cycle every 50 seconds as long as it is in bypass mode. If you turn the inverter back on it will function normally again.

 

[Mattb4]

When you turn off the power switch you are not putting the inverter into Bypass mode. It should still charge from PV and be able to access the units panel display and ability to adjust settings. It should turn off the inverter output. It will not reduce internal consumption of the unit since that comes from the DC side of things. Bypass function only occurs when you have AC in going to AC out.

That said your unit should not be doing much more than charging (and the fan does kick on on occasion even at night from heat buildup) during the day. When you first turn off the switch you should get an error beep.

Based on your description it likely will take someone watching the video to see the fault.

ETA: Incidentally when it loses AC in and you have the power switch on, if you are already in AC bypass, the unit will turn on the inverter and transfer like a UPS does. At this point it can not transfer back into Bypass until AC in is regained.

Further add: BTW if you want to reduce internal consumption the most you would select low power mode in the settings.

 

[RCinFLA]

It is not clear in the video that you have shore power present or not.

I would make a wild guess that the 50 second interval would be inverter periodically re-referencing grid sync if grid is still applied to inverter input so it is ready to bring up inverter from standby if needed due to insufficient battery or solar power available and grid drops. If it does not detect an AC input voltage present it should not bother with any resync'g.

Any re-sync'g should be a background task that should not cause such a dramatic event. It might do something like this if it detects AC input but is unable to sync to it for some reason.

Is is normal the green LED continues to blink? Many inverters blink the AC input LED when it detects AC input voltage but then turns solid green when inverter sync's with AC input and closes pass-through relay.

 

[Off Gridin' It]

When you turn off the power switch you are not putting the inverter into Bypass mode. It should still charge from PV and be able to access the units panel display and ability to adjust settings. It should turn off the inverter output. It will not reduce internal consumption of the unit since that comes from the DC side of things. Bypass function only occurs when you have AC in going to AC out.

That said your unit should not be doing much more than charging (and the fan does kick on on occasion even at night from heat buildup) during the day. When you first turn off the switch you should get an error beep.

Based on your description it likely will take someone watching the video to see the fault.

ETA: Incidentally when it loses AC in and you have the power switch on, if you are already in AC bypass, the unit will turn on the inverter and transfer like a UPS does. At this point it can not transfer back into Bypass until AC in is regained.

Further add: BTW if you want to reduce internal consumption the most you would select low power mode in the settings.

Bypass mode is what the Tier one tech at Signature solar called it when the inverter switch is in the off position it "Bypass" the inverter. So maybe his terminology was wrong. But yes when I do that the solar will be charging and there will be no AC output. But every 50 seconds the error recurs. When the inverter power switch is on everything works perfectly with no issues. You will probably have to see the video to understand what is happening. It's very weird and I haven't seen this happen when I have installed other SPF 3000 inverters.

 

[Off Gridin' It]

It is not clear in the video that you have shore power present or not.

I would make a wild guess that the 50 second interval would be inverter periodically re-referencing grid sync if grid is still applied to inverter input so it is ready to bring up inverter from standby if needed due to insufficient battery or solar power available and grid drops. If it does not detect an AC input voltage present it should not bother with any resync'g.

Any re-sync'g should be a background task that should not cause such a dramatic event. It might do something like this if it detects AC input but is unable to sync to it for some reason.

Is is normal the green LED continues to blink? Many inverters blink the AC input LED when it detects AC input voltage but then turns solid green when inverter sync's with AC input and closes pass-through relay.

There is no shore power or generator connected. After I completed the install I tested both shore power and generator with it and it worked perfectly. With no shore power or gen physically connected and when turning off the power switch so that only the MPPT is functioning and so that only solar would be charging I then get the error.
Yes, the green light will blink over (AC/INV) indicating that it is supplying AC power to the loads and the green light will blink over (CHG) indicating that the battery is charging.

 

[Mattb4]

Bypass mode is what the Tier one tech at Signature solar called it when the inverter switch is in the off position it "Bypass" the inverter. So maybe his terminology was wrong. But yes when I do that the solar will be charging and there will be no AC output. But every 50 seconds the error recurs. When the inverter power switch is on everything works perfectly with no issues. You will probably have to see the video to understand what is happening. It's very weird and I haven't seen this happen when I have installed other SPF 3000 inverters.

Does not give much confidence in SS if their Tier one people do not know how the product they sell and support is supposed to work. Once you wire it to the battery the unit is on waiting for how you set it up. It can operate without AC input and it can operate without PV input if you flip the switch to turn on the inverter for AC out.

Sounds like you have a bad controller.

Edit: I manged to watch your video. Just for reference I setup my spare Easun AIO with bat and PV and no AC in. When I turned off the power switch it simply displayed the PV to bat symbols and also turned of the yellow inverter indication light. I did not get an all LCD panel indicators lite up on nor a fan cycle no matter how long I waited.

 

[Off Gridin' It]

Does not give much confidence in SS if their Tier one people do not know how the product they sell and support is supposed to work. Once you wire it to the battery the unit is on waiting for how you set it up. It can operate without AC input and it can operate without PV input if you flip the switch to turn on the inverter for AC out.

Sounds like you have a bad controller.

Edit: I manged to watch your video. Just for reference I setup my spare Easun AIO with bat and PV and no AC in. When I turned off the power switch it simply displayed the PV to bat symbols and also turned of the yellow inverter indication light. I did not get an all LCD panel indicators lite up on nor a fan cycle no matter how long I waited.

I am beginning to believe that the inverter is defective as well. Fortunately, I have another SPF 3000 for another upcoming project coming up so if it is bad I can just swap it out really quickly. But I hope it is just something simple that I am missing.

 

[Mattb4]

Incidentally I can confirm that with my AIO even in Eco, or low power setting, it still draws ~50w. The only way you can really save on idle power loss is to turn off both the AIO's power switch and the battery disconnect (if you have one installed inline or you would need to disconnect the cables from battery).

It might be possible that a firmware upgrade would correct your units every 50 second full system check when power switch is off.

 

[Zwy]

I have been having an issue with the Bypass function on my Growatt SPF 3000TL LVM-24P Inverter.

I have provided a link to the videos showing the errors and settings. One is the error itself and one is a vid of the settings.
Please take a look and help me solve this problem.

I have tried a lot of different settings and this error still occurs even with the AC Distribution panel breaker disconnected.
All connections are solid and gas tight.

I am working with Signature Solar on the problem and they escalated the call to the higher ups but so far they have not gotten back to me.

This is installed in a 30 amp camper.
2013 Coachman apex 278rls - 30 feet

How much PV? And what do you have for series/parallel connections?

It is in the United States so our voltages here are 120 volts.
Thanks!
https://www.dropbox.com/sh/e3jll87u7nu11a3/AAAvzrlPIl-emjPSL3nC2GC4a?dl=0
Link to Error video and settings

Something to be aware of in low light conditions is the GW will boot up when PV voltage is high enough but when the SCC puts on a load, the PV can't supply enough watts and the voltage will drop. The GW will shut down. When PV voltage rises again, it will repeat the process. This will drain the battery as the boot sequence is powered off the battery.

On my truck camper I have a switch to turn PV off in low light conditions such as parking in a shed or shop with the doors open. There is just enough PV voltage the unit will boot up and start the process. Switch is shown here to the right, just one of those heavy duty battery switches. When evening comes I just turn it off and turn it back on in the morning.

 

[Off Gridin' It]

How much PV? And what do you have for series/parallel connections?

There is 1185 watts.
It is (3) 385 watt panels and they are run in parallel. The client camps in a lot of shade areas so needed the protections of the 3P configuration.

Total array specs.
3P: 49.6 volts at 29.7 amps

 

[Zwy]

There is 1185 watts.
It is (3) 385 watt panels and they are run in parallel. The client camps in a lot of shade areas so needed the protections of the 3P configuration.

Total array specs.
3P: 49.6 volts at 29.7 amps

The amps are high enough. GW has never given a spec for the max amps in this model, I've looked multiple times. It is however 2000w so if you divide that by 145V max input it comes up to the 13a range. It could be around the 20a range like most GW units.

I would run one panel for input and see what the result is.

 

[Off Gridin' It]

The amps are high enough. GW has never given a spec for the max amps in this model, I've looked multiple times. It is however 2000w so if you divide that by 145V max input it comes up to the 13a range. It could be around the 20a range like most GW units.

I would run one panel for input and see what the result is.

I have a second Growatt SPF 3000 so I am going to put one of my extra 400 watt panels on it and a 1500 watt heater as a load and a 100ah LiFePO4 battery I have and see if I get the same error with the factory settings. If it works then I will configure it with the same settings I have on the one in the RV and see if the error occurs. If it works at least I can rule out the settings and it will likely be a defective Growatt.

 

[Zwy]

I have a second Growatt SPF 3000 so I am going to put one of my extra 400 watt panels on it and a 1500 watt heater as a load and a 100ah LiFePO4 battery I have and see if I get the same error with the factory settings. If it works then I will configure it with the same settings I have on the one in the RV and see if the error occurs. If it works at least I can rule out the settings and it will likely be a defective Growatt.

Would be easier to just unplug one or two panels and get the amps down, then see if the problem remains. If you are overloading the MPPT concerning amps, it could damage the MPPT. Let's say you have already damaged the current MPPT and have determined to replace it with another. Most likely it will be repeat damage.

I've looked for the amp spec but can never find it.

 

[Off Gridin' It]

Ok, UPDATE TIME!
So signature solar told me that they think the Growatt SPF 3000 is defective. However, since I had another SPF 3000 on the way already for another install I decided to wait to send it back and do a bench test of the new unit with all the factory setting In place.
So I decided to use (2) Renogy Gel batteries I had sitting around to make the 100ah 24 volt battery bank and connected a 395 watt solar panel.

With only those connections and the factory settings I still got the same error. I am beginning to think that there is some bigger issue with the base software in the inverters. I did a firmware update on the other inverter that is already installed and I still had the problem.

Take a look at the videos I linked and tell me what you think.

LINK:

Videos

Shared with Dropbox

www.dropbox.com

 

[Zwy]

Watched the first video. You need to monitor PV voltage thru the process. Partly cloudy day, the PV could drop yield enough to stop charging. Second, if voltage drops, it's quite possible you have a connection from PV that is intermittent. Considering both inverters are doing this, my thoughts are there could be a problem with PV.

Now went to last video, at the 37 second mark you show a flat mounted panel that is shaded almost 50%. Until this is corrected, you can't really blame the SCC.

 

[Off Gridin' It]

UPDATE! PROBLEM SOLVED

I solved this problem.

I didn't have any luck with signature solar or with Growatt USA but after a lot testing this is what I found out.

Bottom line is that the MPPT voltage limit is 30 - 115 volts. The incoming voltage with the three 395 watts panels in parallel is 49.5 volts.
With some efficiency losses and (Winter) the incoming voltage was fluctuating between 36 to 47 volts. This was still within the MPPT voltage limit specs. However, the Growatt still apparently didn't like that and considered that voltage to be to low and that would cause the MPPT charge controller to attempt to shut down and immediately start back up every 50 seconds.

So I bench tested a second SPF 3000 and put two 395 watts panels in parallel for a total incoming voltage of 49.5.
I still got the error. I then changed the solar panel configuration from 2P to 2S and I was now at 99 volts.
Then I was able to turn off the Inverter side and the MPPT charge controller kept working perfectly. I still don't know why the MPPT charge controller wouldn't work with the parallel configuration. Either the 3P on the RV install or the 2P on the bench test. It just needed more voltage.

I had never had this problem before because I have never done an install with a parallel config producing such low voltage. All the systems have built have been larger.

Signature Solar is aware of the problem and didn't know how to fix it but now they have this fix. They are running it up to Growatt to see what they say about this problem. When I contacted Growatt directly they also didn't have a fix.

Im glad I figured it out. So now my customer has to decided if he wants to buy a 4th panel and put it into a 1580 watt 4S config or delete a panel and do a 790 watt 2S config.

 

[Mattb4]

Good job of figuring out what was causing the situation. Since the voltage was not lower than spec it should not cycle. That is something for the Growatt programmers to fix. Probably won't since few people will run into it. Those that do and complain they will likely just be told to increase panel array voltage.

 

[Zwy]

UPDATE! PROBLEM SOLVED



Signature Solar is aware of the problem and didn't know how to fix it but now they have this fix. They are running it up to Growatt to see what they say about this problem. When I contacted Growatt directly they also didn't have a fix.

The GW is working just as I described it will under low light or low yield conditions. There won't be a fix, the problem really isn't the GW, the problem is PV.

Flat mounted panels seem more prevalent to this issue, any shading with the flat mount and the PV can not supply the load the SCC puts on PV.