Hi All,

Newbie so go slowly please  . 

System Specs:

12 x 260 watt ReneSola panels

2 x 5 KVa Axpert (RCT) Inverters in parallel

8 x Trojan T105 lead acid batteries

No BMV installed

System is 3.5 years old (other than checking the batteries this is the first time I'm having to try and learn quickly to solve my issues)

Recently batteries started fizzing and bubbling away producing excessive heat and also leaking electrolyte.  I reduced charging voltage and switched to Solar only as charging source to try and preserve the batteries while I attempted to work out what went wrong.  My original installer has gone AWOL and no longer in business.  Have had the batteries tested by another local installer and they confirm the batteries are done for.

Original settings when batteries started their nonsense:

Program	Setting
00	ESC
01	SbU
02	20A
03	APL
04	SdS
05	FLd
06	Enabled
07	Enabled
09	50Hz
11	10A
12	48V
13	54V
16	Snu
18	Off
19	Stay at latest screen
20	Lon
22	AOF
23	byE
25	FdS
26	58.4V
27	54.0V
28	PAL
29	42.0V
30	OnE
31	SbE

 

My questions:

• Is 3.5 years a reasonable life for lead acids?
• What is a recommended replacement as a storage solution?  Lithium (Pylontech or similar)? Super Caps? Or Should I be getting a second opinion on the current batteries?
• Recommended Cape Town installer who understands the Axpert setup and can do the correct firmware upgrade?  (Welcome to message me directly if it may be considered advertising).
• How do I determine the current firmware version?
• Been following the discussion regarding CoCT registration and am getting very discouraged regarding Axperts and Grid-tied Hybrid not being able to comply with the regulations – where to with this one?  Original electrician did provide a CoC.

Thanks for the great forum.  Have already learnt a heap from following a few discussions.

BTW - attached is the label from one of my inverters.

35 minutes ago, CT_Solar said:

Is 3.5 years a reasonable life for lead acids?

Hi CT_Solar. Cannot comment on the settings, but for T105's 3.5 years is a bit low.

Unless you have used the down to 50% every day? Or the SOC was misjudged by the Axpert due to it using the voltages?

Send you a PM re. where to take the batteries.

Hi CT_Solar

In my opinion there is not much you could change in terms of settings. The one thing I would do is change setting 16 to OSO (Only SOlar) so that if your batteries are discharged you wait till morning to recharge your batteries. With your current settings your batteries discharge early evening and then you use grid (expensive energy) to recharge them only to discharge them again the same night. So you have a series of mini cycles every night which could explain the premature failure of your Trojans.

With 2 Axperts on 225Ah battery bank you have  the ability to make your batteries work hard. I am not saying you did but that size battery bank is the minimum for one Axpert.

Your current firmware you can determine using the up and down keys below the LCD. U1 is the inverter firmware and U2 is the SCC firmware.

So to sum up I think a combination of mini cycles, too small a battery bank and the known charging bug in the vanilla Axpert firmware has probably done your batteries in.

Your complete description has made it easy to diagnose.

Hi Chris,

Thanks for your valued input. 

My suspicions are probably confirmed then, i.e. the nightly mini-cycles and the Axpert charging bug has killed my batteries.

Can anyone message me with a recommended installer in CT that understands Axperts and can upgrade firmware and perhaps assist with general maintenance in future?  Any recommendations for battery replacement?

Thanks again Chris.

I am coming to CT in the second week of October - and can do your firmware - can you wait that long?

You need to be able to do the general maintenance otherwise it is going to become expensive.

 

Thanks Chris , that would be fantastic and greatly appreciated.

Are you happy with your Pylontech so far?

28 minutes ago, CT_Solar said:

Thanks Chris , that would be fantastic and greatly appreciated.

Are you happy with your Pylontech so far?

Very. Yesterday was one of those non solar days and as an experiment I said to my wife the maid could iron. When I came home in the evening we were on 96% SOC. Lithium seems just be able to scrounge charge on cloudy days. One of the differences is I can charge at 100A whereas previously I was charging at 30A. All that cloud edge effect energy goes straight into the batteries whereas I could not utilise it all previously.  At night I can power our 2000W microwave off the 4 Plyontechs I have. In the mornings we are between 40 and 50% SOC having consumed 100-120 Ah overnight. I have a little reserve - there is no maintenance and I can draw 100A from them continuous if I need which with the way I have set my system up is more than I will need. The absolute bonus is that should I choose to enlarge the system I can just add more modules. I use to operate off 260 Ah lead acid and now I have got 200Ah Lithium. It is like its my birthday every day.

Sounds like Christmas.... I've been looking at the US2000 B x 4 in a rack.  How easy is would it be to hook these up to my current setup?

44 minutes ago, Chris Hobson said:

Very. Yesterday was one of those non solar days and as an experiment I said to my wife the maid could iron. When I came home in the evening we were on 96% SOC. Lithium seems just be able to scrounge charge on cloudy days. One of the differences is I can charge at 100A whereas previously I was charging at 30A. All that cloud edge effect energy goes straight into the batteries whereas I could not utilise it all previously.  At night I can power our 2000W microwave off the 4 Plyontechs I have. In the mornings we are between 40 and 50% SOC having consumed 100-120 Ah overnight. I have a little reserve - there is no maintenance and I can draw 100A from them continuous if I need which with the way I have set my system up is more than I will need. The absolute bonus is that should I choose to enlarge the system I can just add more modules. I use to operate off 260 Ah lead acid and now I have got 200Ah Lithium. It is like its my birthday every day.

Could it not be that there are clouds but still enough "UV". Sometimes depending on the "clouds" the impact of it pushes my solar panels  up to 6 amps above the amps suggested by the manufacturers.  Clouds does not always mean no charging