Please help clarify some stuff for me.....

[Hannah Barnes]

Hi. Strictly speaking I am not really starting out in solar as I have been off the grid for almost 4 years. 

I have 8 x 6V Trojan T105's (Golf cart ones) and a Mecer/Axpert 5Kva/4000w inverter with 6 x 270w panels. 

I have no backup so the sun and batteries are my only supply meaning they have probably worked quite hard over the 4 years and survived my ignorance. I hope to invest in a generator in the near future for additional backup. 

I sourced the equipment but have had someone helping me with my solar in terms of installation and maintenance. I need to get more hands on so that I can take over the maintenance myself. I will not attempt any installations myself however. 

My batteries have really done well these past 4 years but this year we have had so much rain (this is great) and overcast days and I am running a pressure pump and borehole pump at times, so the system seems to be taking some strain. I have started having people stay over weekends with a ministry we are running so that increases my load also. 

It seems to make sense to replace the batteries with 1 x 3.5Kw Pylontech (financial constraints at the moment but will look at getting another one as soon as possible) and try to add another 6 panels. 

It seems that the Pylontech batteries are compatible with the Axpert inverter but you have to have the ICC software - is this correct? And then which one do I have to buy - there seem to be a few. 

I have not done any firmware updates - my inverter shows 72 version - do I need to update the firmware and can I just update to the latest firmware update before changing over to the Lithium batteries? (The inverter was bought in June 2015)

So to change over from the faithful Trojans to the lithium ion batteries I would need to buy: 

The Pylontech 3000b battery

Cables

6 Solar panels (270 w which would increase my input to 12 solar panels)

ICC software....which one? 

And do I need the brackets or can the batteries stand on a wooden strut like my Trojans? 

Any help and further recommendations will be appreciated. 

 

 

 

 

 

 

 

[Jaco De Jongh]

1 hour ago, Hannah Barnes said:

So to change over from the faithful Trojans to the lithium ion batteries I would need to buy: 

 

2 of the 3000U will give you a bit more kwh than your existing bank. 

1 hour ago, Hannah Barnes said:

And do I need the brackets or can the batteries stand on a wooden strut like my Trojans? 

The brakets offer you the required space between the batterys for cooling ext.. You can however save some money and create your own way to space them a bit apart to allow for air to flow.

1 hour ago, Hannah Barnes said:

Cables

When you buy the Pylontecks, you can buy a cable set with it. it will allow for connection from the Bats to the fuses and from there to the inverter. 

 

[Coulomb]

1 hour ago, Hannah Barnes said:

my inverter shows 72 version -

That's the major version number; there is another pair of digits after the 72 that's very important.

Quote

do I need to update the firmware

That's entirely up to you; there is no requirement. However, if you have a model that is suitable for patched firmware, you'll get some benefits, especially after you upgrade to LFP batteries. Disclosure: I'm one of the patched firmware authors. See Can I update my firmware, and if so, to what?

The patched firmware will make various settings more LFP friendly, and KettleKomp™ may help prevent your inverter from thinking it's overloading when the battery voltage sags due to load. It's usually used for preventing the inverter from switching over to "line mode" where the AC-in powers the load, but you don't have an AC-in source, by the sounds of it.

[Hannah Barnes]

Thanks so much for the input. I have a limited budget at the moment. Would it be better to rather try get 2 x Pylontech 3000 and leave the 6 additional solar panels for now or get the one 3000 and the additional 6 x solar panels? 

The two digits after the 72 are 40. i will have a look at the firmware thread thank you

[Abe53]

IMHO, Get more solar panels before adding more battery.

[jasonvanwyk]

10 hours ago, Hannah Barnes said:

And do I need the brackets or can the batteries stand on a wooden strut like my Trojans? 

Hi Hannah.

The battery cabinets are just plain computer networking switch or server cabinets. they come in various sizes like 9u and 12u etc. You can buy good second hand ones on classified sites like gum tree and olx etc. I've seen a 9u for R600 before - that would hold 3 or 4 Pylontech 2.4KWh batteries.

[Hannah Barnes]

5 minutes ago, jasonvanwyk said:

Hi Hannah.

The battery cabinets are just plain computer networking switch or server cabinets. they come in various sizes like 9u and 12u etc. You can buy good second hand ones on classified sites like gum tree and olx etc. I've seen a 9u for R600 before - that would hold 3 or 4 Pylontech 2.4KWh batteries.

Thanks Jason. Seeing your setup and so many panels, may I ask...how quickly do your batteries charge on a rainy day? 

[jasonvanwyk]

2 minutes ago, Hannah Barnes said:

Thanks Jason. Seeing your setup and so many panels, may I ask...how quickly do your batteries charge on a rainy day? 

I've only been up and running for about 3 weeks now. I've had 2 rainy days where my batteries did not charge fully (bear in mind I am a heavy user in terms of 1 borehole pump, swimming pool pump and 2 pressure pumps, and lots of washing during the day. I also had incorrect settings on the charge amps, so I was only allocating 20 amps to charge my batteries instead of 100amps. perhaps a better constant would be to tell you how quickly they charge up on a good sunny day - in that case, at this time of the year the batteries start to charge from a 25% SOC at about 7:00 and are fully charged by 10:00-10:30. I hope this helps.

[jasonvanwyk]

2 minutes ago, jasonvanwyk said:

I've only been up and running for about 3 weeks now. I've had 2 rainy days where my batteries did not charge fully (bear in mind I am a heavy user in terms of 1 borehole pump, swimming pool pump and 2 pressure pumps, and lots of washing during the day. I also had incorrect settings on the charge amps, so I was only allocating 20 amps to charge my batteries instead of 100amps. perhaps a better constant would be to tell you how quickly they charge up on a good sunny day - in that case, at this time of the year the batteries start to charge from a 25% SOC at about 7:00 and are fully charged by 10:00-10:30. I hope this helps.

I forgot to add - i've managed to cut down my night time consumption, and so my batteries have not gone to below 44% SOC over the last three days and I've been off grid now for 3 days

[Hannah Barnes]

1 minute ago, jasonvanwyk said:

I forgot to add - i've managed to cut down my night time consumption, and so my batteries have not gone to below 44% SOC over the last three days and I've been off grid now for 3 days

Thanks very much. That helps. I think it will definitely help me to up my solar panels first with one battery and add another battery later. 

[phil.g00]

4 hours ago, Abe53 said:

IMHO, Get more solar panels before adding more battery.

+1