Hi, we recently purchased a large solar system with 2 Lithium ION 3.522KWH batteries, 9 330watt Canadian solar panels and a 5KVA Mercer Inverter. we are just having some issues with it and maybe someone can help clear things for me. For some reason the solar panels cut off and stop powering the house and the batteries. We got an electrician in to adjust some settings to configure with the batteries as we suspected the inverter and the batteries were not communicating properly. We changed them to our liking and also to what he thought was preferable but then the solar panels started to hang and not put power in to the house and not charge the batteries from about 10am onwards. We would have to reset the whole system to get the panels to start charging the batteries again. However, yesterday my mother decided to switch setting 5 to AGn and this suddenly made the solar panels start charging the batteries and everything started working as intended but we don't know if this would have negative affects on our lithium batteries. If someone could assist this would be of great help.

1 hour ago, Ninoevans said:

Hi, we recently purchased a large solar system with 2 Lithium ION 3.522KWH batteries, 9 330watt Canadian solar panels and a 5KVA Mercer Inverter. we are just having some issues with it and maybe someone can help clear things for me. For some reason the solar panels cut off and stop powering the house and the batteries. We got an electrician in to adjust some settings to configure with the batteries as we suspected the inverter and the batteries were not communicating properly. We changed them to our liking and also to what he thought was preferable but then the solar panels started to hang and not put power in to the house and not charge the batteries from about 10am onwards. We would have to reset the whole system to get the panels to start charging the batteries again. However, yesterday my mother decided to switch setting 5 to AGn and this suddenly made the solar panels start charging the batteries and everything started working as intended but we don't know if this would have negative affects on our lithium batteries. If someone could assist this would be of great help.

Welcome Nino

The Axpert experts will be with you shortly. This just seems like a settings issue, but I havnt worked on a Voltronic for quite some time and am not up to date with them anymore. 

Okay thank you. Yes we think it is a setting too, just need to figure out exactly what setting.

2 minutes ago, Ninoevans said:

Okay thank you. Yes we think it is a setting too, just need to figure out exactly what setting.

Maybe to save some time, and make it easier for thew guys to help you. Please list your settings below, and they might also ask you what version Firmware you are running?

 

okay i will list them when i am available to do so, thank you. Within the next hour or so.....

The word document below are all the settings which we have enabled on our inverter. We have not listed the settings which are at default setting. the link provided is to the Manual for our mercer inverter for anyone who needs to reference to it.

 http://www.solarwholesale.co.za/Axpert MKS-MKS PLUS 1-5KVA Manual on 20140306.pdf

User manual - word.docx

Do you have info on your battery model?

your bulk setting is higher than your float as a start which is wrong.

(Do you have info on your battery model?) - Yes i do i i will add the file below

(your bulk setting is higher than your float as a start which is wrong) - Oh okay so my float needs higher than my bulk charge? i would think it would need to be the other way around. i though when it goes in to bulk charge it would try to push as much charge in to the battery as possible.

The spec sheet is on page 5 of the document attached.

PYLON-US + Phantom training.pdf

34 minutes ago, Ninoevans said:

(Do you have info on your battery model?) - Yes i do i i will add the file below

(your bulk setting is higher than your float as a start which is wrong) - Oh okay so my float needs higher than my bulk charge? i would think it would need to be the other way around. i though when it goes in to bulk charge it would try to push as much charge in to the battery as possible.

The spec sheet is on page 5 of the document attached.

PYLON-US + Phantom training.pdf 2.35 MB · 1 download

sorry i meant to say your float is higher than your bulk, your bulk should be higher. from your document your current float is 54 and bulk is 50?

which of those models do you have and how many? it will depend on what you make setting 2

imo your settings should be:

02 - depends on answer above?
05 - USE
12 - 48
13 - 51
26 -  53.2
27 - 52
29 - 47.5

Hi, sorry for not elaborating on the particular battery.

The model we have is the US3000 model so the biggest one and we have two of them. We do have setting five set to user defined.

Our setting 2 is at 60A it can go all the way up to 140A as ours is a 5KVA model

 

1 hour ago, Ninoevans said:

Hi, sorry for not elaborating on the particular battery.

The model we have is the US3000 model so the biggest one and we have two of them. We do have setting five set to user defined.

Our setting 2 is at 60A it can go all the way up to 140A as ours is a 5KVA model

 

60A is good i believe. I think if you adjust your other settings as above it should be in order.

Thank you. we will monitor it and let update as we go

 

First find out what you're Mecer is called in "MPPsolar language". After that you can look up your settings in this document:

Pylontech inverter setup SOP.pdf

Also you can make a connection via ICC software.

Thank you very much, im not too sure on how to find what language my inverter is but i will try to find out

On 2019/10/09 at 8:58 PM, Ninoevans said:

For some reason the solar panels cut off and stop powering the house and the batteries.

You have setting 01 at SOL, which means the inverter stops using battery energy (presumably charged from solar panels) at sunset. At night, the loads are powered from AC-in (utility). Is this what you mean by the above? SOL is an unusual "solar UPS" setting, for keeping the battery as full as possible at all times.

You probably want SbU mode (Solar first priority for powering loads, then battery, then utility). It will let you use your stored solar energy at night, and only switch to utility when the battery voltage falls below setting 12 (the back to utility voltage).

Edit: also, you don't want settings 12 and 26 to be the same, as your installer seems to have done. You want setting 12 to be significantly below settings 26 and 27, otherwise the battery will immediately be considered weak, and the inverter will switch to line mode (AC-in/utility powers the loads). As already mentioned, setting 27 (float voltage) should be lower than setting 26 (bulk/absorb voltage), though it is my understanding that the inverter will not let you set them the other way around anyway.

Edited October 11, 20195 yr by Coulomb

I think we are missing something important here. There have been a number of reports by Users that the new Axperts have a bug on their pv side when using it with LiFePO4 batteries.

@Ninoevans was experiencing the same problem until his Mother changed setting 05 to AGM, then he reports that the PV system was working as normal.

Can setting 05 not be the solar bug on the new Axperts?

Yes, I do realise this, but the fact that the solar system worked normally on this setting could mean something...not so.

Maybe @Coulomb can look into this if the OP can confirm.

Edited October 11, 20195 yr by GVC

14 hours ago, GVC said:

changed setting 05 to AGM, then he reports that the PV system was working as normal.

I would not leave it on AGM setting; as @DaveSA says, 56.4 V is way too high for PylonTechs. Using that setting forced some other settings (like setting 12) to effectively take on normal values. Just get the settings sensible, as per the PylonTech recommendations, except for setting 29, as below:

Edited October 12, 20195 yr by Coulomb
Various tweaks to the table

Hi Coulomb 

I will be installing 3 numbers US3000 sometime next week.

going by your analogy (3x 35) = 105A rounded down to 100A.

Just wondering if charging the batteries  with 100A is not on the high side?

1 hour ago, hancock said:

Hi Coulomb 

I will be installing 3 numbers US3000 sometime next week.

going by your analogy (3x 35) = 105A rounded down to 100A.

Just wondering if charging the batteries  with 100A is not on the high side?

you are charging them at ~33A each which is perfectly fine.

20 hours ago, hancock said:

Just wondering if charging the batteries  with 100A is not on the high side?

Not at all, as @Dex_ has stated. At 5000 W load, you're discharging at some 108A (using 50 V battery and 93% efficiency). Again, split over 3 battery modules, so some 36 A each.

Hi everyone thank you for the replies, they have been most helpful. We have been changing settings to what everyone has recommended and gotten help from some electricians too, but even though the settings are as good as can be there are still some problems. the solar panels seem to keep cutting off at times, especially when solar power would be most effective; so from about 10am to about 3pm, unless we manually reset. We have not really been able to figure out why this is happening or the pattern of it.

Someone recommended the SBU setting on the forum although we thought that is was the best setting as well it is the setting that seems to give us the most problems. The SBU setting seems to cause more of the PV cut offs and sometimes taking Utility as priority in the middle of the day instead of solar power. 

Thank you very much for the help, it is really appreciated. If anyone can still help us on the issue that would also be greatly appreciated.