Gatvol/Fed Up - Growatt (Installer Issues)

[DieDusman]

Long story short, I have a 3kW Growatt Inverter, 2 x 200AH Lead Acid Gel batteries and 3 x 330W Canadian solar panels.

The people who installed my system did not quite know what they were doing and this became evident when they procduced a COC without any labels or blanking plates on the DB boards.

The settings on the inverter were mostly left defualt and I familirised myself with the various options.  About 2 months in, I started to have issues where the inverter would switch between the utility power and battery every few minutes (only at night when the solar was not carrying the load), with the lights in the house flickering every time. I changed the 3rd option from APL to UPS to see if it makes a difference, but alas, it didn't.  Every time it switched over, my pc would reboot, until I got fed up and got a seperate UPS for it.

So last week I noticed that my solar charge during the day is hovering around 80W, down from the usual 500W+. Then load shedding started... Guess what, my power only lasts about 5 secs before the inverter shows 0V output, with the battery still at 26.0 V.

Any ideas? Anyone willing to hazard a guess as to where I can start to poke? The supplier of the system has been promising to send soemone to check for the past two weeks, but I am not in the mood to be left in the dark until then.

TIA.

Screenshots of a normal day with the frequent switching, then another when it all went fubar.

[DieDusman]

My settings:

01 SbU
02 50A
03 APL
04 SdS
05 USE
06 LTE
07 tfd
08 230V
09 50hz
10 2
11 20A
12 23.0V
13 27.0V
14 CSO
15 BOF
16 LOF
17 AOF
18 bYE
19 28.2v
20 27.0v
21 21.0v
22 SbE
24 NEC dlS

[___]

Sounds like a bad battery. It does not accept charge (hence the only 80W incoming from PV), but drops out the moment it has to take load.

To confirm, use a multimeter and measure the voltage on the battery while adding a load to it (or dropping the grid). If I am right, the voltage takes a nose-dive, and then quickly bouces back once the inverter switches off.

Likewise, when the sun is up it charges to 28.2V really easily.

Also, I am quite amused at how language express this feeling. While in Afrikaans we might have a stuffed digestive tract, the Germans would have trouble breating. Ich habe die Nase voll! And it it is a particularly bad day, Ich habe die Schnauze voll!

Hopefully the installer is not someone who likes to dance on your nose

 

[DieDusman]

52 minutes ago, plonkster said:

Sounds like a bad battery. It does not accept charge (hence the only 80W incoming from PV), but drops out the moment it has to take load.

To confirm, use a multimeter and measure the voltage on the battery while adding a load to it (or dropping the grid). If I am right, the voltage takes a nose-dive, and then quickly bouces back once the inverter switches off.

Likewise, when the sun is up it charges to 28.2V really easily.

Also, I am quite amused at how language express this feeling. While in Afrikaans we might have a stuffed digestive tract, the Germans would have trouble breating. Ich habe die Nase voll! And it it is a particularly bad day, Ich habe die Schnauze voll!

Hopefully the installer is not someone who likes to dance on your nose

 

Hi Plonkster, thanks for the reply. Yeah, I am trying to gather as much info as possible so that the installer cannot bull schei$$e me  

Anyway, did the test with the multimeter. It read 26.2V and almost immediately fell to 25.7V when I removed the mains, which is still well within the operating range.  I suspect the inverter is faulty. Luckily it is still under warranty, as it was only installed in Feb 2020.  Ideally I would like to get someone to do a basic survey at my place to see what needs to be done in terms of correctly installing the system. I know my DB is not done to COC standards, I have heard that my three panels might be wired incorrectly, etc.  The problem is, nowadays everyone is a solar expert, but very few really understand the ins and outs.  Ask me something about Azure or Active Directory, don't ask me something about PVs  

[___]

1 hour ago, DieDusman said:

26.2V and almost immediately fell to 25.7V when I removed the mains

Well that is not reason for concern, that is quite normal. What I mean is that once you put load on, the batteries dive to below 24V very quickly, and the moment you put the charger back on they quickly rebound to over 27V. Anyway, that's what you got to do first. Watch the battery voltage while putting load on and charging it. A good battery will carry the load while the voltage sinks slowly over several minutes/hours, remaining above 24V most of the time (assuming your loads are within reason). Then when you start recharging it, the reverse will happen. The batteries will accept lots of charge current for several minutes/hours and the voltage will pick up slowly, only reaching >27V when the battery is over 80% full.

Good batteries have some "weight" to it, it won't be swung up and down quickly. Bad batteries pull down and up easily.

1 hour ago, DieDusman said:

Azure or Active Directory

When I run into that stuff I head for the hills. I can't find my way around an M$ system at all anymore. Ever since they removed My Computer from the desktop (which was shortly after I didn't need Windows in my life anymore, some time around 2004) I can't find anything anymore. People are like "ooooh your Open Source stuff is so user unfriendly" and I'm like... no... it just picks different friends...

 

[DieDusman]

Problem is, the inverter refuses to carry any load for more than a second without the mains (was not always the case). When I view the data, it shows that the output is something like 1.6V @ 50hz

[Chris-R]

Can't agree more with @plonkster. I would also say that you have a bad battery there. Try the test Plonkster is suggesting, else remove one of the batteries and do the test whilst hooked up with battery cables and try to start your vehicle.

 

[MLFourie]

I am having the same problem. I supply and also install alternative energy products.

I have had endless problems with this inverter, a 3kva 48V Growatt, connected up as batterybackup only, no panels. First the inverter malfunctioned about a month after being installed. Was working perfectly fine before that. No changes were made.

It was send back to the importer who informed me that the motherboard was damaged and therefore the warranty is null and void. 

I accepted this as a power surge was very possible, although all the protection was in place and functioning. I gave the go-ahead for them to repair the inverter. 

They sent the inverter back and it kept giving a 0 output. 

I sent it back to the importers who could find no fault.

Again was sent back to me. Again I am experiencing the same problem. 

I had my technician rewire the entire installation and still, the same problem. We have checked everything, electrical, batteries, items on the circuit, no faults.

I then fitted a loan unit for my customer (a 3kva 48V Victron Multiplus) and the loan unit functions perfectly.

Again I sent the Growatt to the importer who informs me that they find no fault with the unit, and don't know what to tell me or what the problem could be.

Now I also have another customer that phoned me also with a 3kva Growatt and it seems like he is experiencing the same problem .

I have even mailed the manufacturer, 6 hrs ago.

I seriously doubt that I will supply a Growatt again.

can someone maybe give me some advice???

Mail or WhatsApp me please.

[email protected]

084 717 4502