Good day guys. I am in desperate need of help again. 

Soooo, my 5kva/5000w Axpert stops accepting pv power at random points of the day. It reads an incomming voltage from thr pannels but the watts produced is 0 and is just running from battery power. 

I am totaly clueless and am getting irittated by this thing. 

Is it maby something to do with the OCv or can it br something else. It also seems to be whenever I start a big load of like 2-3Kw

I am running 12 330w Suntec solar pannels. 4 sets of 3 per set.

Edited May 19, 20197 yr by Corne Landsberg

1 hour ago, Corne Landsberg said:

Soooo, my 5kva/5000w Axpert stops accepting pv power at random points of the day. It reads an incomming voltage from thr pannels but the watts produced is 0 and is just running from battery power. 

Is it possible that it's a clone inverter? Some of the clones seem to have this problem.

1 hour ago, Corne Landsberg said:

Is it maybe something to do with the OCv or can it be something else.

It could well be the OCV. Your panels have a Voc of 46.2 V. For 3S that's 138.6 V; the solar charge controller (SCC) starts derating (producing less power) at 130 V. That's 50.0 V @ 0°C. Your SCC has a maximum permitted panel voltage of 145 V, so on cold mornings, you are at risk of blowing up the SCC part of the inverter. You're at the maximum Voc at 11°C, which could be quite common in the next few weeks. So whether this is your issue or not, it seems you need to change to 2S instead of 3S.

Is it possible to check the panel voltage next time it happens? You might need to use a multimeter instead of reading the voltage from the inverter.

1 hour ago, Corne Landsberg said:

It also seems to be whenever I start a big load of like 2-3Kw

I don't immediately see how these are connected.

29 minutes ago, Coulomb said:

Is it possible that it's a clone inverter? Some of the clones seem to have this problem.

I do not think it is a clone inverter. Everything seems to check out acording to the post you have linked. 

I have managed to narrow done to see that the issue happens at mid day Everytime. The voltage the pannels are at before it happnes is round aboit 95v once it happnes the inverter reads 122v and the multimeter reads 123v so not that big of a difference. 

I understand that i might have a problem on cold mornings but this is happening mid day as soon as I start a big load. 

Is there maby a place i can send a video of it to you once it happens? 

Edited May 19, 20197 yr by Corne Landsberg

36 minutes ago, Corne Landsberg said:

I have managed to narrow done to see that the issue happens at mid day Everytime. The voltage the pannels are at before it happnes is round aboit 95v once it happnes the inverter reads 122v and the multimeter reads 123v so not that big of a difference. 

Ok. That's pretty convincing that panel Voc is not the root of the no-solar-power issue.

What battery do you have? It may be too small, such that a 3 kW load might cause a battery voltage dip. I'll have to go check some firmware code to see if a difference in voltage reported by the SCC and the battery might cause the SCC to reset or to stop charging. Though I don't see why a battery voltage dip should cause more of a difference than normal.

Just now, Coulomb said:

Ok. That's pretty convincing that panel Voc is not the root of the no-solar-power issue.

What battery do you have? It may be too small, such that a 3 kW load might cause a battery voltage dip. I'll have to go check some firmware code to see if a difference in voltage reported by the SCC and the battery might cause the SCC to reset or to stop charging. Though I don't see why a battery voltage dip should cause more of a difference than normal.

I have 2 5.8Kw Huawei litium bateries in parallel. It is 48v batteries with 120Ah storrage. 

31 minutes ago, Corne Landsberg said:

I have 2 5.8Kw Huawei litium bateries in parallel. It is 48v batteries with 120Ah storrage. 

Ok, I would think that would be strong enough. I'm out of ideas, sorry.

Hi Corne

We have exactly the same problem, except our panels only kick in when high load starts (i.e. when pool goes on). When pool goes off (as well as before going on), system runs batteries and never seems to charge from panels. We have same same inverter and batteries except our panels are 4 x 2S. We have settings suggested by Chris Hobson 29 Nov 2018.

We would also really appreciate any advice.

Hi @Corne Landsberg and @Liz

There are a few guys experiencing the same issue at the moment with Axpert Inverters. (Sound like the issue is with 2018 and 2019 models)

I am also struggling with the same issue whereby the PV Watts will drop to zero and it will take about 30 to 40 seconds to recover. The PV Watts will also freeze up sometimes twice a day. (If it freeze you only need to switch off the PV supply to the inverter and switch it back on after about 60 seconds)

I am also experiencing the most dips in PV Watts between 11:00 and 13:00. Sometimes it is load related and other times it dips with the slightest changes.

Mustek (Inverter supplier) is currently investigating this issue for us.

See PV Watts trend below:

I did change the Bulk Charging Volts from 53.5V as per recommendations for LiFe batteries to 54.1V at 13:16 on the graph above. I was very excited about the improvement but today it almost did the same between 11:00 and 13:00 as yesterday. I must admit that it is better now but the problem still exist.

Hope the manufacturers come back with a solution fast.

Go and follow "Axpert - strange behaviour (Potential MPPT issue)" on this forum, to be kept updated.

 

7 minutes ago, Jaco Venter said:

Hi @Corne Landsberg and @Liz

There are a few guys experiencing the same issue at the moment with Axpert Inverters. (Sound like the issue is with 2018 and 2019 models)

I am also struggling with the same issue whereby the PV Watts will drop to zero and it will take about 30 to 40 seconds to recover. The PV Watts will also freeze up sometimes twice a day. (If it freeze you only need to switch off the PV supply to the inverter and switch it back on after about 60 seconds)

I am also experiencing the most dips in PV Watts between 11:00 and 13:00. Sometimes it is load related and other times it dips with the slightest changes.

Mustek (Inverter supplier) is currently investigating this issue for us.

See PV Watts trend below:

I did change the Bulk Charging Volts from 53.5V as per recommendations for LiFe batteries to 54.1V at 13:16 on the graph above. I was very excited about the improvement but today it almost did the same between 11:00 and 13:00 as yesterday. I must admit that it is better now but the problem still exist.

Hope the manufacturers come back with a solution fast.

Go and follow "Axpert - strange behaviour (Potential MPPT issue)" on this forum, to be kept updated.

 

Dear Jaco. It seems we had a clone inverter which is okay for lead acid batteries but not for lithium. We got inverter exchanged and seems to run perfectly now

1 minute ago, Liz said:

Dear Jaco. It seems we had a clone inverter which is okay for lead acid batteries but not for lithium. We got inverter exchanged and seems to run perfectly now

Very interesting:

What model inverter are you using, and what year was it manufactured?

Where did you buy the clone from? and where did you get the new one from?

I did replace an inverter once but the same problem exist.

13 minutes ago, Jaco Venter said:

Very interesting:

What model inverter are you using, and what year was it manufactured?

Where did you buy the clone from? and where did you get the new one from?

I did replace an inverter once but the same problem exist.

See images, and also follow Coulomb"s page on "Do I have a clone"

Bought Inverter from same place that ecxhanged with no prob....they were awesome 

 

8 hours ago, Liz said:

Bought Inverter from same place that ecxhanged with no prob....they were awesome 

I note that the replacement inverter isn't quite the same; it has a 120-430 V MPPT range, compared with 60-130 V for the clone. So you may well need to reconfigure your solar panels, if that's not already done.

18 minutes ago, Coulomb said:

I note that the replacement inverter isn't quite the same; it has a 120-430 V MPPT range, compared with 60-130 V for the clone. So you may well need to reconfigure your solar panels, if that's not already done.

Yes thank you. Reconfigured to 3x3 strings.