Growatt 3000 LVM possible inverter issues

[Gaze]

Right now, I have a 12V, 420Ah portable system with a Giandel 2200W inverter I built for my RV, hard wired into the system we installed where the Growatt was. Everything is running fine since last night with no flickering or compressor issues. It is only my opinion that the Growatt is either defective, or that model has problems with running more than one inductive motor at one time due to noise feedback.

Flickering lights on my single fridge, not even trying to run two.

 

[Gaze]

This is very likely nothing to do with the rods in the ground.
Its very likely about having multiple bonds between neutral and ground.
You can isolate your panels for a test.

By isolate "panels" you mean electrical panels (main vs sub)? not solar panels

 

[Mac6792]

I have a similar issue with my system. For me this is an appliance issue. I have a fridge and freezer along with a bunch of other stuff running with no issue. Once I add my other fridge and the compressor is on the lights in the fridge flicker. They also flicker on leds that are also being powered by that same inverter I have two. One tell tell sign is when the fridge is on and compressor is running, the invertor shows wattage consumption bouncing all over the place. Pull all the loads off your inverter and add each of your compressor based appliances separately to see what the wattage consumption looks like The one that's bouncing all over the place is likely the problem one.

 

[rcrracer]

Will EMI filters, line reactors, inductors, chokes, etc. fix these types of problems? Are these types of problems only seen with high frequency inverters or do low frequency inverters also have these types of problems?

 

[Zwy]

Good question, looks like @Bud Martin is having the same issue, my Growatt has a 240v 75lbs transformer so without an Oscilloscope or others suggestions, I could not tell you. Mabe someone else can chime in.

I looked for the thread, have a link?

 

[Zwy]

As I understand it, the Growatt will unbond neutral and ground when powered by AC input, but will automatically bond ground-neutral when running from battery/solar, after the ATS makes the transfer. Could that be creating a problematic ground loop? This would explain why a different inverter you hooked up does not cause the same issue as the Growatt? Can the Growatt be set to NOT do its N-G bond thing? I believe there may be a setting for this (#24 possibly?).

This is from Filter Guy in the Resources section. It can be downloaded from this page here: https://diysolarforum.com/resources/grounding-details-for-specific-make-model-of-inverters.156/

As it states, when ATS is engaged, N-G bond is broken and both are transferred thru the ATS to the 120v N-G bond at the service panel or main bonding. When on battery power, N-G bond is inside the Growatt and the ATS has fully opened the N and G circuits to the service panel or main bonding.

Brand:
MPP Solar
Model: LV2424
Description: ALL in one Inverter Charger
Information provided by:
FilterGuy
Source: Product Manual and Company Support
Confidence in information:
Med High
Notes:
•
This unit would work well as a back up power inverter with a hook up to a residential grid.
•
If used with a generator, the generator should have a Neutral Ground bond.
The manual says:
11. GROUNDING INSTRUCTIONS This inverter/ charger should
be connected to a permanent grounded wiring system. Be sure to
comply with local requirements and regulation to install this inverter.
Emails From MPP Solar Support:
1)
Is the AC In ground, AC out ground and Chassis ground all tied together? yes
2)
Is there any bonding between the AC Neutral out and AC Out Ground? If not, is there any problem if there is a Neutral Ground bo nd in the circuit after the inverter?
T he output N G is handled this way when under line mode (AC bypass), N G is open, but when under inverter mode, then N G will s hort. There shouldn't be any problem
to the inverter itself if you wish to N
G short manually, however we're told some countries (like Australia) require N G to sta y open when grid passes through so that’s
the reason it's designed this way.
When asked about the configuration setting above, They said:
Please ignore this setting as essentially it is the same as what I've described in the last message about how OUTPUT N
G is hand led under different
modes so it's already now done internally and this setting would have no use.
thanks

Automatic
AC: When powered from the AC
in, the inverter does not bond Neutral to ground
BAT: When powered from the battery, the inverter does bond Neutral to ground and
totally disconnects from the AC in.

 

[beetlefan]

Will EMI filters, line reactors, inductors, chokes, etc. fix these types of problems? Are these types of problems only seen with high frequency inverters or do low frequency inverters also have these types of problems?

@Repro mentioned earlier that both of his two HF inverters 2200w/12v Giandel and 1500w GoPower do not have this kind problem

 

[Joe BoyKey]

I looked for the thread, have a link?

Post #22 of this thread

 

[Zwy]

Post #22 of this thread

I don't Bud was having problems, he was quoting the post above it. But he did bring up an important point relative to the conversation, "So the problem just started? It was running with the two fridge in the past with the same exact setup fine without any flickering until now?"

Which appears later was answered as the problem was present since day one.

 

[Zwy]

A bigger inverter would be a jump to 48V. That would require a lot of $ for more batteries to meet the 400Ah (minimum suggested) for the 48V Growatt. I am thinking about going with a Victron Multiplus 24/3000 120V. Found one on sale for $1095. I have read that it can be configured with "solar as priority", and draw from the grid when the batteries reach a low voltage set point. I already have a VE 150/45 SCC. It all depends on what happens with the Growatt. I will post after I know. Thanks again Joe!

I think it would be easier and probably wiser to just add another Growatt in parallel.

 

[Repro]

@Repro mentioned earlier that both of his two HF inverters 2200w/12v Giandel and 1500w GoPower do not have this kind problem

That is true. Right now, I have my 12V Giandel 2200W inverter connected to the four 12V AmpereTIme 200Ah batteries. The inverter is grounded, and I have two refrigerators, a wash machine.... running with no problem. I also ran one fridge and an upright freezer with my GoPower 1500W with no problems. Both inverters were connected to the wiring we installed for the Growatt.

 

[Repro]

I don't Bud was having problems, he was quoting the post above it. But he did bring up an important point relative to the conversation, "So the problem just started? It was running with the two fridge in the past with the same exact setup fine without any flickering until now?"

Which appears later was answered as the problem was present since day one.

The flickering was only seen in the refrigerator's as they were the only things with lights running on solar. The flickering only happens when the compressors on both fridges were running at the same time. Also, when they run at the same time, it starts flickering very little. The longer the compressor ran together, the more intense the flickering got. Therefore, it was not caught early on. We noticed it the first time about a week after we installed it, and I didn't think much of it. I started making it a habit to go and check the fridge when I heard it run. I started seeing the flickering because I was opening the fridge more and more often. It made me crazy because it didn't happen all of the time.

I started digging into the issue intensely, and it took me over a week to figure out that it was only happening when both fridges were running. We could reproduce the flicker by turning the fridge temp down on both fridges to get them to run. We started diagnosing the wiring. We were so sure it was something we did. No matter what we checked, everything was right. During this phase, we ran the wiring again and installed conduit. We double checked all connections and ensured that everything was up to code. When the system passed inspection, we asked the inspector about the flickering. After a short conversation, he asked if we had checked the inverter for issues. I then started researching the internet, talking to the dealer, did resets, and finally posted here. That whole process took a long time. It seems like it is hard for some readers here to get that.

I got some good tips here and we concentrated on the grounding with no luck. Only after removing the Growatt and installing my Giandel inverter did I realize where the problem was. The dealer has been a great sport and is taking the inverter back. I am going to order a new inverter. I am looking at a VE MultiPlus right now. I already have a VE 150/45 SCC, Cerbo GX and a VE smart shunt that I got for my RV. So I have everything but the inverter/charger. I am talking to the dealer about configuration. Once I am convinced it will do what I want, I may spring for it.

I hope that clears up what happened.

 

[Gaze]

This is from Filter Guy in the Resources section. It can be downloaded from this page here: https://diysolarforum.com/resources/grounding-details-for-specific-make-model-of-inverters.156/

As it states, when ATS is engaged, N-G bond is broken and both are transferred thru the ATS to the 120v N-G bond at the service panel or main bonding. When on battery power, N-G bond is inside the Growatt and the ATS has fully opened the N and G circuits to the service panel or main bonding.

Brand:
MPP Solar
Model: LV2424
Description: ALL in one Inverter Charger
Information provided by:
FilterGuy
Source: Product Manual and Company Support
Confidence in information:
Med High
Notes:
•
This unit would work well as a back up power inverter with a hook up to a residential grid.
•
If used with a generator, the generator should have a Neutral Ground bond.
The manual says:
11. GROUNDING INSTRUCTIONS This inverter/ charger should
be connected to a permanent grounded wiring system. Be sure to
comply with local requirements and regulation to install this inverter.
Emails From MPP Solar Support:
1)
Is the AC In ground, AC out ground and Chassis ground all tied together? yes
2)
Is there any bonding between the AC Neutral out and AC Out Ground? If not, is there any problem if there is a Neutral Ground bo nd in the circuit after the inverter?
T he output N G is handled this way when under line mode (AC bypass), N G is open, but when under inverter mode, then N G will s hort. There shouldn't be any problem
to the inverter itself if you wish to N
G short manually, however we're told some countries (like Australia) require N G to sta y open when grid passes through so that’s
the reason it's designed this way.
When asked about the configuration setting above, They said:
Please ignore this setting as essentially it is the same as what I've described in the last message about how OUTPUT N
G is hand led under different
modes so it's already now done internally and this setting would have no use.
thanks

Automatic
AC: When powered from the AC
in, the inverter does not bond Neutral to ground
BAT: When powered from the battery, the inverter does bond Neutral to ground and
totally disconnects from the AC in.

Yeah, I read that resource a while back. Thanks, FilterGuy.

 

[rcrracer]

If things function OK with just one freezer running at a time, you could wire up something like a GTR8I-M1 multi function timer from Amazon or Ebay. Have it switch the hot back and forth between the two freezers on a set interval like 30 min. As far as the other loads, they can be controlled manually using three way switches .Hot connected to the com. screw, each of two loads, connected to a traveler screw. Electricity can only go down one path. If more loads need to be controlled, use 3 three way switches. Hook com. of each of two three way switches to one of the traveler screws of the third three way switch. Now there are four traveler screws that can be hooked to four loads. Still there is only one path the electricity can take.

 

[MrTrevino]

Hi Everyone, I am having a similar issue. Here are the details. I own a Growatt 3000 24V. For the last 3 weeks it has been powering about half of my house load with no issues. In this load I have a 25ft brand new fridge. Recently I decided to also add a chest freezer(1 year old) to the load. Here is were some of the house lights started flickering. Here is what I have noticed. In the kitchen I have two lights fixtures. Each has 2 x 60watt incandescent light bulbs. When the two fridges are running, if I turn on one of the lights the bulbs start flickering. But as soon as I switch on the second light(for a total of 4 x60watt bulbs) the flickering stops. Seems like flickering only occurs when the inverter is powering a small load. I decided to try one 100watt LED bulb instead of 2 x 60 incandescent bulbs and to my surprise the flickering does not occurs when powering LED bulbs. A smart solution is to replace all of the incandescent lights bulbs with LED ones. But still I'll like to know what can be causing this.

 

[getalab]

I’m having issues with a GW 3000/24 as well, my AC out has a open ground. Vendor said to put it in “standby” mode by turning off inverter, but switching back on before display went dark. All this did in my case was bypass the batteries, and use utility, where I have good ground.
I think this grounding box would work in my case with program 24, but my unit skips that one. Mine goes from 22 to 28, which isn’t even in the manual.

 

[Repro]

Program #24 is only in use when two or more Growatt's are connected in parallel (expansion). Sorry, I forgot to reply to the previous posting.

 

[Repro]

I’m having issues with a GW 3000/24 as well, my AC out has a open ground. Vendor said to put it in “standby” mode by turning off inverter, but switching back on before display went dark. All this did in my case was bypass the batteries, and use utility, where I have good ground.
I think this grounding box would work in my case with program 24, but my unit skips that one. Mine goes from 22 to 28, which isn’t even in the manual.

Program #24 is only in use when two or more Growatt's are connected in parallel (expansion).

 

[getalab]

Program #24 is only in use when two or more Growatt's are connected in parallel (expansion).

It mentions that in program settings, but doesn’t mention it in the dry contact signal section of manual..so, I don’t know.

 

[Jamsolar876]

The flickering was only seen in the refrigerator's as they were the only things with lights running on solar. The flickering only happens when the compressors on both fridges were running at the same time. Also, when they run at the same time, it starts flickering very little. The longer the compressor ran together, the more intense the flickering got. Therefore, it was not caught early on. We noticed it the first time about a week after we installed it, and I didn't think much of it. I started making it a habit to go and check the fridge when I heard it run. I started seeing the flickering because I was opening the fridge more and more often. It made me crazy because it didn't happen all of the time.

I started digging into the issue intensely, and it took me over a week to figure out that it was only happening when both fridges were running. We could reproduce the flicker by turning the fridge temp down on both fridges to get them to run. We started diagnosing the wiring. We were so sure it was something we did. No matter what we checked, everything was right. During this phase, we ran the wiring again and installed conduit. We double checked all connections and ensured that everything was up to code. When the system passed inspection, we asked the inspector about the flickering. After a short conversation, he asked if we had checked the inverter for issues. I then started researching the internet, talking to the dealer, did resets, and finally posted here. That whole process took a long time. It seems like it is hard for some readers here to get that.

I got some good tips here and we concentrated on the grounding with no luck. Only after removing the Growatt and installing my Giandel inverter did I realize where the problem was. The dealer has been a great sport and is taking the inverter back. I am going to order a new inverter. I am looking at a VE MultiPlus right now. I already have a VE 150/45 SCC, Cerbo GX and a VE smart shunt that I got for my RV. So I have everything but the inverter/charger. I am talking to the dealer about configuration. Once I am convinced it will do what I want, I may spring for it.

I hope that clears up what happened.

I'm running the same inverter with a side by side Frigidaire refrigerator..I get the same flickering when I run my Samsung washing machine ..the flickering only occurs when the machine motor comes on and off as it's one of those oscillator types. It appears to just be due to the high load draw and the high frequency inverter design of the Growatt. I'd purchase another one and just go parallel.