Hi all. I bought new battiers for my solar system and now need to know what the correct settings on my axpert 48v system should be for them to last as long as possible. Please let me know if you need more info.

You didn't say what model your Axpert is (there are many 48 V models). If it's the most common 5 kVA size, then 100 Ah of battery is a bit low; 200 Ah is recommended by the manufacturer. Try to keep the loads low.

If it's the 5 kVA size, read about the premature float bugs, and consider patched firmware to correct these. To get the right version firmware, see Can I Update my firmware, and if so to what?

Hi. Thanks i will check and revert to you. I only want to use the battery system for power failures. I have 12 x 250W Panels that I want to use during the day If need be to charge and for loads. The rest of the time i will use utility.

3 hours ago, djacobs said:

I only want to use the battery system for power failures
I have 12 x 250W Panels
... want to use during the day If need be to charge and for loads.
The rest of the time i will use utility.

I only want ... asy and simple words ... yet behind them a whole new world is going to open up.

Let the journey begin DJacobs. It will be fun, they said.

Sorry, I could not resist. :-) 

On a serious note. All of us here on PF where we can will help you make it happen DJacobs.

Haha, Ja been struggling with my system for almost 4 years now already. Due to bad installations. Trying to sort out myself. All my batteries got seriously damaged. The weekend they all finally had there last breath. So I had to make a plan to get these 4 as my system needs batteries attached.

6 minutes ago, djacobs said:

... almost 4 years now already.

Start the process over with the new batts by giving the guys your exact inverter model, all the settings, loads and all that so that the batts last this time.

And don't be worried like @plonkster - give it to us so that we can see what not to do, that you can do it right. :-) 

Thanks Gents. 

1 - sol

2- 20a

3 - apl

4 - sds

5- use

6 - ltd

7 - ttd

9 - 50hz

11 - 20a

12 - 47v

13 - 48v

16 - snu

18 - bon

19 - tep

20 - lon

22  - aon

23 - bye

25 - fds

26 - 56.4v

27 - 52.8v

28 - sig

29 - 46v

30 - one

31 - sbe

 

@djacobs, you have an inverter model similar to mine: 5 kVA, 4 kW, 2015 manufacture. Your settings seem reasonable, with these notes.

• Setting 27, float voltage, seems low, at 13.2 V per nominal 12 V module. Check with the battery datasheet or what's written on the front (I can't read it from the photo).
• You might try UPS for setting 3; it's the fastest switching to minimise flicker when the power goes down, or the chances of computers (etc) resetting. But if power quality in your area is poor, you might have to stick with APL.
• I think you may as well turn on fault recording, setting 25 = FEN.
• Setting 29, low cutoff voltage, is probably too high. It will override your settings for going to utility and back (settings 12 and 13). But if you don't have anything else (like a BMV) to protect your battery, you could keep this high setting, but settings 12 and 13 would effectively become 48 and 50 volts (2.0 and 4.0 volts above the battery low voltage cutoff voltage (setting 29) respectively.
• Setting 18: do you really want that beeper on all the time? 

Hi Thanks. I saw this, this morning 06.18am. Why is utilty not charging my battiers if solar is insufficient. Is it becuase of option 1 - sol? I need the batteries to stay full for that emergency situation.

Edited January 18, 20197 yr by djacobs

4 hours ago, djacobs said:

Hi Thanks. I saw this, this morning 06.18am.

Eek! You have 175 V there [ edit: no, it's 175W, see below ], when your PV input maximum voltage is 145 V (and PV charging will reduce when the PV input voltage is over about 130 V). You'll have to reconfigure your PV panels from 4S to 3S, I'm guessing. Perhaps even to 2S.

Quote

Why is utilty not charging my battiers if solar is insufficient. Is it becuase of option 1 - sol? I need the batteries to stay full for that emergency situation.

No, utility charging is all about settings 12 and 13, and setting 29 if it's close to these. The battery voltage will have to come below the "battery low" voltage before utility charging will start. That's the lower of setting 12 and (setting 29 + 2.0 V). So with setting 29 at 46 V, that will be 48 V (even though setting 12 is 47 V). I thought that you wanted to keep utility charging to a minimum with those figures. To keep them really topped up, you should increase setting 12 to perhaps 51 V (12.75 V per 12 V module). Put setting 13 one or two volts above whatever you decide for setting 12. You may need to experiment with setting 12 to get the behaviour you want. Note that while utility charging, the loads will be supplied from utility power (it will be in bypass mode). So you'd prefer that this was all over by the time the PV input is good (perhaps 7 or 8 am).

Edited January 18, 20197 yr by Coulomb

No it is 175W on the screen. My panels are already in Series of 3.

1 hour ago, djacobs said:

No it is 175W on the screen.

Ah, my mistake; I could not see the units due to a reflection. The utility should still come on if the battery voltage drops below the "low battery" mark, as explained earlier. With 175 W going into them, that's less likely.

Edited January 18, 20197 yr by Coulomb

Hi All, i did a test by switching off utility to check my battiers at 19.15. The result was that they where empty and not charged so that would have ment that if we had power failure we would have been in the dark. I took this picture. Somewhere there is a setting wrong whereby the batteries are not kept full. I have set all settings as suggested above. What else could be the problem. The picture does not show but battery was on one bar and emmediately died.

Edited January 21, 20197 yr by djacobs

So the settings are

12 - 51v

13 - 53v

18 - snu

26 - 56.4

27- 52.8v

29 - 48v

Hi all your feedback will be appreciated.

 

Thanks

On 2019/01/22 at 3:20 AM, djacobs said:

i did a test by switching off utility to check my battiers at 19.15.

Perhaps we could start with this. So these are brand new batteries, correct?

Four 12 V modules in series, two such strings in parallel?

Is 19.15 supposed to be a voltage? As measured by the inverter, or a multimeter? If so, it's way too high for a single module, and way too low for a string of four in series. Please tell us about how these battery modules are configured, and the thickness of the cables.

With no load, what is the voltage across each 12 V module (or at least a few of them)?

As an interim measure, please increase setting 27 (float charge voltage) to 54.0 V (13.5 V per 12 V module). That might at least get some charge into the battery, until we can figure out what else is wrong.

Hi All, really need you help again. And please any info rwquired I will assist. I can not find thr spec of these batteries to make sure my setting are correct.  The system indicates that it is charging the batreries but it is not. As soon as therebis a load such as a kettle it drops to one bar. Yes the system indicates that it is fully charged on the screen.

Edited May 21, 20197 yr by djacobs

Perhaps you could answer some of my questions above:

* Are there 4 or 8 12 V modules in your battery? 

* Have you raised your float voltage setting (27) to 54 V as I suggested? 

* What is your main (U1) firmware version?

I think you'll need to update to a later firmware version, day 73.00e, to overcome the premature float bug. Later firmware versions will have the timed absorb feature, which may be needed to fully charge your battery when we don't know how high a charge voltage is safe.

Hi,

There are 4 x Batteries in the string. Yes setting 27 is at 54. And the firmware is U1 72 40.

2 hours ago, djacobs said:

There are 4 x Batteries in the string.

So 100 Ah of lead acid battery is considered very light; the manual recommends 200 Ah for a 5 kVA model (even a 4 kW model, as yours is). So a kettle load might be around 3000 W, or about 3300 W on the battery side, so about 0.65C for a 100 Ah battery. Its voltage would be expected to sag significantly under load, so the 1 bar (I assume this is on the LC Display) is not unexpected.

Quote

Yes setting 27 is at 54. And the firmware is U1 72 40.

Good on both counts. It means that there is a chance that the battery isn't getting fully charged due to the premature float bugs. You should watch a solar charge to ensure that the battery is getting to over 56 V for at least half an hour, or you might be able to dig that out of logs from Watchpower. If you think it's not getting fully charged due to the charge bug (only one applies to your older firmware), then you should consider updating to patched firmware version 73.00e.

Thanks Coulomb. As a stupid oke reading all that information on the other forum has me totaly confused. Is there a Dummy guide on how to update firmware. 

What do I have to look for on my inverter that I dont stuff it up.