1 hour ago, TaliaB said:

If you read the original post from Pat de Klerk he was using 2 x 100ah lead acid so obviously he is running a very conservative load hence the reason i suggested Pylontech up2000 instead of 2 x 12v drop in lipo with 2 diffrent bms"s that can't communicate with each other or the inverter.

Yes I did read it. The point you raise about lead acid. They can produce 600A X 24V if required for a short period vs 50A X 24V for the Pylontech. 

I think its important to alert that the Pylontech will limit the output to 1.2kW.

There are a lot of other options at 1C. Yes the single BMS is better but cannot talk to the inverter. 

I don't think it is such a bad idea to use 2 x 12V drop ins plus a R900 battery balancer. 

10 hours ago, Scorp007 said:

Yes I did read it. The point you raise about lead acid. They can produce 600A X 24V if required for a short period vs 50A X 24V for the Pylontech. 

I think its important to alert that the Pylontech will limit the output to 1.2kW.

There are a lot of other options at 1C. Yes the single BMS is better but cannot talk to the inverter. 

I don't think it is such a bad idea to use 2 x 12V drop ins plus a R900 battery balancer. 

You are limited with lead acid constant current draw of C20 that means with 100ah( 2 batteries in series stays 100ah) that you should only draw 5 amps @ 24v otherwise suffer the Peukert's effect. (loss of capacity)

The problem with drop in lfp is they are normally 2000 cycles where Pylontec are 4000-6000. Yeah sure 1C with 3kva inverter will be a better fit.

I have recently installed 1 x 2.6KWH 24V SunX Lithium Ion Battery Pack bought from nm-tech in Pta for 14.5k so far no complaints.1C 4000 cycles @ 80 dod. You could try them Pat that is if they will have stock left.

https://nm-tech.co.za/products/2-6kwh-24v-sunx-lithium-ion-battery-pack?variant=42813068214429

Many thanks for the info ! Will certainly explore this route. Just a question regarding the BMS - does the Axpert have communication capability for this. If so, how to connect (I have no documentation for the Axpert inverter I have !)

20 minutes ago, Pat de Klerk said:

Many thanks for the info ! Will certainly explore this route. Just a question regarding the BMS - does the Axpert have communication capability for this. If so, how to connect (I have no documentation for the Axpert inverter I have !)

Pat if you send a pic of the front of the Axpert showing the ports I am sure someone will help. As my I think similar Axpert does not have comms I have been running for 15mths with drop inn's using the USR setting for my Hubble S-100. Very happy. 

50 minutes ago, TaliaB said:

You are limited with lead acid constant current draw of C20 that means with 100ah( 2 batteries in series stays 100ah) that you should only draw 5 amps @ 24v otherwise suffer the Peukert's effect. (loss of capacity. 

Thanks for this information of the limitation when using lead acid. If 5A(100Ah) is the limit then trolleys should never be sold with lead acids. 

Hiya,

 

I just installed x2 Hubble lithium Ion batteries and couldn't be happier, I also have an axpert 3k inverter

3 hours ago, Scorp007 said:

Thanks for this information of the limitation when using lead acid. If 5A(100Ah) is the limit then trolleys should never be sold with lead acids. 

They should not hence the reason lead acid trolleys only last 2 to 3 months with current load shedding cycles, the 50% dod challange and longer charging times . That is the reason why lead acid is used in standby applications( large banks to overcome low energy density at continuous discharge eg 20c) and not cyclic applications.

 

You can use a Lithium battery with no problem. The Axpert 3kW inverter assumes a 24V battery. You need to set the battery type to USER in the setup of the inverter (option 5) in the case of the Axpert King. You would also have to play around with options 26 and 27 (Bulk charging and float charging voltage) to suit your battery. Out of the factory, the charging regime of the inverter is optimised for lead acid battery, NOT for LiFePO4. My Bulk charging voltage is 27.2 and Floating voltage is 27.1. However, this depends on the exact battery you use. The big difference between lead acid batteries and Lithium is in stable voltage. Lead acid batteries love being fully charged at around 13V.  The policy is then to charge the lead acid battery fully, and not run it down too low. With Lithium, the policy is very different. LiFePO4 patteries love being around 50% charged, so one would cycle the battery so that the output power available crosses 50% SOC every day. They do NOT like being charged to the absolute maximum or being totally discharged. Forget the rubbish that the sales people banter that one can discharge a Lithium battery from 100% down to 0%. Of course that IS true, one CAN do that, but this would shorten the life of the lithium battery to a fraction of its expected life span of at least 4000 charging cycles. I cycle the battery around 50% SOC. From that you can decide how much power you require from the Lithium battery, probably using between 50% to 80% of the total battery capacity with each charge cycle.  My battery is built up from cells and  battery management hardware. If you use a Pylontech or similar pre-built battery the charge/discharge parameters would be handled by the battery software using the dedicated communications link between inverter and battery. However, this is a much more expensive approach.

Generally a good post but for the charging value of lead acid at around 13V. If only charged to 13V they will not last. 

As for lithium I use about 0.2V higher. I also don't charge to 100% daily or discharge below about 15%.

On 1/14/2023 at 4:41 PM, Pat de Klerk said:

I wish to install a Lithium battery on my Axpert 3kVA - 24V inverter system. Firstly, can this inverter be configured to charge lithium properly/safely ? Secondly, any recommendations for this Lithium battery - size, make, supplier in SA etc ?  

The system has been operating very successfully with two 12volt flooded lead acid batteries (100Ah) in series for about 10 years, with battery replacement every 3 years or so. However, with the current load shedding schedules, I'm deep cycling up to three times a day ! The batteries are not going to last long at this rate.  May as well look for something more robust !

Hi! 

Yes, the Axpert 3kVA - 24V inverter system can be configured to charge lithium batteries properly and safely. However, it's recommended to check with the manufacturer or a qualified electrician to confirm that the inverter is compatible with lithium batteries and that the proper charging settings are used.

As for the lithium battery, it is recommended to choose a battery with a capacity that can handle the load and depth of discharge (DoD) required for your system. The capacity you choose will depend on the amount of power you need to store and how often you need to discharge the battery. A common lithium battery type is LiFePO4 (Lithium Iron Phosphate), which is known for its long life, high stability, and high current discharge capability.

In South Africa, you can find lithium batteries from various suppliers, including PowerBrick, Energi TriPak, and GetPower. It's always a good idea to compare the specifications, warranty, and cost of different options before making a decision.

It's also important to note that the installation of a lithium battery requires specialized knowledge and should be performed by a qualified electrician. Additionally, the battery bank should be properly sized and configured to ensure optimal performance and longevity of the batteries.

Hheheh Anyone here that could point me in the right direction ?? I've replaced my Bats finally.

On 2023/02/03 at 11:59 PM, GRAYSON said:

Battery and Solar Solutions

Good day, I have a 3kW 24V Growatt inverter and my installer recommend 2 Hubble lithium batteries S120 12V 1,5KWH 120AH. The challenge is that I cannot get these batteries, what other battery can I use. I only want to run my lights, TVs, WIFI and Fridge.

My experience with the Axpert 3kW 24 V inverters set up as UPS's is the following : I have found that the lead acid typically last about 2.5 years before people notice that it cant run the full 2 hours of load shedding . Another case we have over sized the installation with 160Ah x2 and that because it dont see the deep discharges has been lasting well . The obvious answer is Lithium but it is considerably more expensive but is the best return for your money . I have been using the Blue Nova 24 V mini and also the  Blue Nova Mobile Power Series (MPS) 12V 1.4 batteries with the Axpert 24V and had good results - It can charge quicker . Just check the individual batteries every 6 Months and then charge them individually to balance . 

The new option is that Blue Nova now has launched a 24V Version of their Mobile Power Series (MPS)- Effectively a 1.4k in a 24 V setup - so no need to balance charge these anymore. 

Hi please can anyone tell me what add settings are for the mecer 5kw inverter and 2 x 4.8 kw mecer lithium battery is it 0100 and 2nd battery 0000 mecer can’t even tell me 

Hi guys can anyone tell me what add settings to use on a mecer 5kw inverter and 2x 4.8kw mecer lithium batteries even mecer can’t tell me is it 0100 and 2nd battery 0000 or because it’s the same brand leave them all down but I’m shore one must be the master or am I wrong please help 

Does your axpert have coms

You would need a cable made with your specific hardware in mind

 

Where you would start is look in the inverter manual

To find the pin-out of the com port ie rs485 or CAN

 

Then in the battery manual find it's pin-out

Have a custom cable made up, with the sides marked ie if you plug the side made up for the battery into the inverter it won't work

Then in the settings you have to select the Li option or whatever settings the manual suggests you change to for lithium

If they don't speak the same language it won't work

And then you just have to use the USE setting and change the bulk and float ,cut-off  voltages to match the battery

If you don't have a manual giving you those voltages you can deduce it, if you know the configuration of the battery ie 15s/16s

 

Edited February 27, 20233 yr by Leondavibe
Correction

The address settings you should find in the battery manual too

You would also need a custom cable made up for this

And check the manual, to determine which port it has to be plugged into

 

Edited February 27, 20233 yr by Leondavibe
Correction

A quick google reveals 

Axpert does not have a batyery type Li se you would most likely 

 have to use USE for user settings and set the voltages manually

 

On the battery if it uses rs485 

You would have in plugged into the port on the left, looks like it needs the first three pins 

Hopefully someone with the same model will chime in

 

Edited February 27, 20233 yr by Leondavibe
more info

Hi Everyone, 

 

I have scanned through this and just have a quick question, I am looking at the Dyness 4,8 KWH (Wall Mount)on my 5KVA RCT (Axpert) inverter.  

It seems that getting a battery with a BMS and that can communicate to the Inverter is key or very important as apposed to voltage management.

I came across the Hoselect battery with the same capacity but cannot find any real confirmation on it and its compatibility with the Axpert. 

The price difference is close to R 4000 so if I can save that for the same capacity and warranties etc that would be great, if any one has some knowledge or can assist that would be greatly appreciated. 

I have a 24v100AH lithium battery and the charge voltage is 25v and the cut off discharge voltage is 16.5v... wanted to ask on how much bulk voltage should i set on my 3kva inverter.. 

12 hours ago, Lowiza94 said:

24v100AH lithium battery and the charge voltage is 25v

25.0 V is way too low for an 8S LFP battery, so it must be something like a 6S NMC battery.

I would use 25.0 V on your inverter's bulk charge voltage setting, and slightly less or perhaps the same for the float voltage. Something like 24.9 V for float.

If you find that the battery voltage is regularly exceeding 25.2 V (4.2 V per cell average), then I would reduce both voltages slightly to preserve battery life.

On 2023/03/06 at 3:06 PM, javadog said:

Hi Everyone, 

 

I have scanned through this and just have a quick question, I am looking at the Dyness 4,8 KWH (Wall Mount)on my 5KVA RCT (Axpert) inverter.  

It seems that getting a battery with a BMS and that can communicate to the Inverter is key or very important as apposed to voltage management.

I came across the Hoselect battery with the same capacity but cannot find any real confirmation on it and its compatibility with the Axpert. 

The price difference is close to R 4000 so if I can save that for the same capacity and warranties etc that would be great, if any one has some knowledge or can assist that would be greatly appreciated. 

Comunication is important if you want to know how much you have left in the tank imo

 

You can operate a battery in dumb node as some say though that is a misreprestation imo

 

As the bms is still managing the battery ,to prevent any damage

 

The only benefit of coms is that you can then force a shutdown on a certain SOC 

And know how much you have left in the tank , though many batteries have a light system to indicate 25/50/70/100% so in dumb mode you would just rely on that

 

Imo the coms is overhyped 

When it comes to loadshedding it can make a difference when you have panels 

 

ie if it is only a battery backup dumb mode works perfectly fine

 

If you have panels and the battery is in play, ie it will use that with panels to meet load , and you want to stop using oower at a certain point to leave a reserve tank for load shedding then an inverter that can use the soc to switch to eskom  can make a difference 

 

But as far as i have it many use a voltage setting for this , the sunsynk can use soc % , so if the inverter cannot use the soc% and rather uses voltage there would be no real benefit to coms imo

Edited May 25, 20233 yr by Leondavibe

Thanks @Leondavibe

Came to the same conclusion, when running the battery and loadshedding, I have a good understanding what we use and what is available as well as the battery BMS gives me sufficient information. I also watched a couple of videos around charge cycles and realised that comms etc is not critical for me esp once I understood the charge discharge mechanics of the LiFe battery (video below helped alot)  

I ended up getting the Shoto 5.12 Kw rack mount battery as my brother uses those in his solar install and has not had any issues over the last couple of years. 

Configured the system to charge at 20A and float at 54v, cut off is 48v and have never got close to using more than 30% of the capacity even on the 4 hour stretches. 

Battery charges back up in about 2-3 hours 

Thanks

 

Good day

Can I use an 24v 106Ah SVolt lifepo4 battery on the RCT Axpert VM 3000VA/3000W invert

3 hours ago, GTJO said:

Good day

Can I use an 24v 106Ah SVolt lifepo4 battery on the RCT Axpert VM 3000VA/3000W invert

I take it this inverter is about the same as my 3kVA Axpert and I would say yes as you should be able to set the charge/discharge levels under the USR type.