Jaco P Bloem

Much appreciated, thanks - yes I am normally hesitant and nervous to update (good thing) and do read up well before doing so. I am just glad the Overvoltage / sporadic trips have been solved..

Hi @Coulomb, I'm glad you have picked up on the conversation. My Inverters (2 in parallel of the 5kW Axpert MKII) are both on 71.92. Fortunately it runs stable since the update about 5 months ago. I found the firmware from a link my supplier send years ago. I'm not sure of the rules to post the link, I will rather send this on your inbox, so you can check? There is an additional setting 14 and 15 as mentioned.. Keep well! Jaco

Hi Chris Yes. My system is stable after the previous update to 71.82 and I also did update a few months ago to 71.92. All really functioning well, so just make sure about the correct firmware for your specific model then you should be good to go! PS : I have posted the FW link to you in your mail box. Not sure what the major difference is to 71.92, although always go for the latest as long as it is stable (mine is). There are two additional settings in 71.92 : 14)Lbd/E and 15)Nbd/E But I will be honest, not sure if they function. Thought it might be the coupling of the Neutral - but my Neutral is connected to earth at the inverter. Kind Regards Jaco

Hi Chris Yes. My system is stable after the previous update to 71.82 and I also did update a few months ago to 71.92. All really functioning well, so just make sure about the correct firmware for your specific model then you should be good to go! Kind Regards Jaco

Great, thanks! Yes I will assist with the cable, laptop and software with instructions (from the Topic feed given earlier)..

Thank-you @Coulomb we will carefully check if this inverter from @KwaadbaarD is not a clone. From the model number, should your post on the firmware for the 48V model not be applicable? https://forums.aeva.asn.au/viewtopic.php?p=77943#p77943 Regards!

Hi, yes I will gladly assist.. I have an old laptop I use with a series port and the Axpert cable. We just need to be very careful to use the correct Firmware file, if you can source the latest file for your inverter (always best to ask your supplier or the specialist in this Forum if you do not have the new firmware). You can email me privately so we can discuss 🙂 Kind Regards Jaco

Thanks Gents, I enjoy also the information! @Leshenon a different but related topic : I know of 2 Sunsynk 8kW installations where the Earth Leakage (home DB) trips after loadshedding. They do not have an earth - neutral bond relay installed, so my quess is when the Eskom / Munic Neutral and Earth return, there is an unbalanced leakage (?). Any inputs or discussions around this that you are aware of? Kind Regards, Jaco

Dankeschön @Payback2! I'm currently using the software by @Solar Assistant and is very impressed. It also utilizes Grafana. Appreciate the gesture.

I'm not familiar with all the settings on this Inverter, but relating them to the 5kVa, they seem correct. I suppose setting 26 is the Charge Voltage which is fine at 2 x 14.1V. Also the float seem in order. The cable size and circuit breakers are in order as long as there is no poor connection and the cables kept short. If the installation and settings are in order, then it may be the battery quality. You should be able to cycle the 2 batteries to 50% (say 24.2V SOC) easily with a load of 175W (<6A) and this should take more than 2 hours. [In fact probably 75%, given they were sufficiently charged]. Can you ask support from the battery supplier, their opinion and perhaps they can do their own (load) test? Regards!

Hi For the benefit of the Forum, could you share more on the specific batteries (make and type) with their Specs used. Secondly post the Inverter settings - so we can see the mode, Charging and Floating Voltages, etc. Keep well Jaco P

This is actually great news especially for Pylontech (and I suppose similar products) owners. So the BMS will treat and charge the new pack differently than the old. I wonder if the supplier still honor the full warranty in such a case - although I understand the warranty is in any case less when used with an Axpert as the Inverter cannot communicate with the BMS (except through 3rd party software like ICC). Important : @It's On if you start too small, I.e. with one Pylontech (3.5kWh) only, there is an issue here to consider.. and this is from actual experience at a friend's installation : When the load exceeds the amp capacity of the single battery pack (70 amp in this case) the BMS will protect the battery and shut off. This in turn causes the Axpert to trip (when in SBU mode) as the DC disappears. This is with zero PV generation and you need just over 3.5 kW of load (oven + microwave) for this to happen. The battery BMS is too quick for the Axpert, we have tried different settings but before the inverter can make a decision on the Voltages, the BMS acts. We have moved this battery to a Sunsynk inverter with communication to the BMS - different story! The Inverter blends the usable battery DC with available solar and grid power without overloading the single battery. So for now with the Axpert, rather spec the battery packs large enough from the start, at least to carry your typical peak load 😅.

..on most parts (i.e PV or even Inverter) you can expand at any time I agree. However you cannot add a new battery pack to an old unit or pairs. The cells did not age together so if you add new cells to old ones you have different charge (voltage) levels which will ultimately decrease battery life. In this case (parallel Axperts) the Battery bank is common to both the Inverters, and so you cannot expand the existing bank say after 1 year without replacing all. It is somewhat logical and is applicable to flooded / agm batteries also. I have found this post interesting : Greetings!

I agree, the Pylontech batteries seem to do well, you can search for the best price. We've bought a set from Ellies, so you can ask a qoute from your local outlet, also check out Bonanza Technologies (excellent advice and support from the owner). My own set does not exist in the market so it won't help. If possible go big from the start - because the battery DC is all connected and bridged, you cannot expand easily if you wait too long. Either 3 x 3.5kWh or 4 x 2.8kWh units if possible. The single big 6 kWh @Krokkedil mentioned can also work depending on your load after sunset.. I was advised 10kWh at the time which works great in summer. For rainy days and those long winter nights it does however still switch back to Utility. Your PV will be sufficient to charge the batteries. Keep well!

Hi, I have a similar setup with the 2 Axperts in parallel however I use two Lithium batteries with their own BMS. My opinion is that these Mecer inverters do not do a great job of charging, if left to it's own devices. If you are going to stick to Flooded (or agm) batteries then you will have to install a 'battery balancer' to balance the 12V units amongst themselves. The inverter do not have any intelligence to do this. I am sure I have seen units for sale in the PowerStore (?). Otherwise move to Life batteries with their own BMS, but this may be expensive.- there is great advice on this Forum for the voltage settings. PS: I presume the Inverters are in parallel with the kit, setting 28 = pal and that the battery DC (48V) is bridged to each inverter. Important also to keep the electric (wiring) distance as equal as possible between the batteries and Inverters. Let us know, good luck! Kind Regards Jaco P