Seplos BMS with Growatt SPF 6000T

[smdl]

Hi, folks.

I'm in the process of putting together my first system, and am preparing for the actual installation. So far, I have purchased a Growatt SPF 6000T, a Seplos Mason DIY kit, into which I am about to install EVE LF280K cells. When ordering the SEPLOS kit, I took care to order the RS485 model (10D), so I think I'm on the right track, but I am struggling to understand how exactly to connect the BMS to the inverter and configure them. The manuals for both units offer very basic information about how things are configured, but without having done anything like this before, I'm seeking something a little more informative. I have done some searching, and am slowly becoming better-informed, but hoping to solicit some input from those more experienced than I. Apologies in advance for the lack of knowledge!

Here are a few things I'm currently wondering about:

1. Are all RS485 RJ45 cables created equally?

2. The Growatt unit has BMS and RS485 ports, with the manual indicating that the BMS port should be used when connecting the unit to a lithium battery. However, being that there is an RS485 port, and the Seplos BMS is RS485, I'm wondering if that is correct?

3. The Seplos unit has two RS485 ports (RS4851 and RS4852). Does it matter which one I connect to?

4. What exactly am I trying to accomplish in setting up communication between the two devices? I assume that there is an established protocol, and I will go through the both manuals to set up as indicated, but it would help if I knew more about what I am trying to do. If there is a good primer on this stuff somewhere, I would love to go through it. Hopefully, someone who has been through the setup with these components can provide some insight.

Thanks for any help, even just pointing me in the right direction!

Cheers,
Shaun

 

[diysaa12]

I just completed setting up eve 16s 280K seplos DIY kit with a growatt spf 5000 ES. I assume this is very similar to your setup. I am at work now but will post my setup pics from both ends (bms and inverter) with comments on things that I discovered along the way after I come back from work tonite.

 

[smdl]

I just completed setting up eve 16s 280K seplos DIY kit with a growatt spf 5000 ES. I assume this is very similar to your setup. I am at work now but will post my setup pics from both ends (bms and inverter) with comments on things that I discovered along the way after I come back from work tonite.

Thanks, I would really appreciate that! Real-world experience on similar equipment can't be beat.

Cheers,
Shaun

 

[diysaa12]

In answer to your questions:

1. I use regular ethernet cables to connect my Seplos BMS with the Growatt inverter and they seem to work okay. Some users have reported problems but it could very well be due to different firmware/software versions of either their inverter or the BMS from mine. Some have used the pin mappings provided in the manuals to make custom cables. I have come to realize that due to lack of proper/consistent version release notes from both Growatt and Seplos the issues facing users of their products differ and so do the solutions.

2. I use the BMS port on the inverter to connect to the CAN port on my Seplos BMS and it works fine. Again I use regular ethernet cables. These instructions can be found in both manuals and they work for me.

3. I use the two other RS4851/2 ports on the BMS to connect to my laptop to configure/monitor the BMS. Either can be used. They are also used to connect two BMS's in parallel.

4. I tried both the "USE2" and "L51" battery settings on the Growatt inverter and found the "L51" to be better since it allows for communication between the two for the following reasons:

A. It allows the inverter to read the capacity of the battery in % accurately which allowed me to set the switch from "Battery to Utility"
and "Utility to Battery" accurately (Refer attached "Growatt Inverter Settings 3"). I prefer using remaining capacity as opposed to voltage.

B. It allows the BMS to tell the inverter to vary the charge (Amps) based on the state of the battery (Refer attached "Growatt Inverter
Settings 2").

C. I can also set the "Remaining capacity Alarm/Protection" on the BMS to be higher than the "Battery Voltage Cut-off Point" on
the Inverter since the BMS has the ability to recover once the desired capacity has been reached without manual intervention.

D. I am not completely sure of this since I have not performed any extensive tests but I do believe the Battery BMS is in a better position to
demand "Charge" or "Discharge" status since it knows the complete cellwise state of the battery.

I am sure there are other situations that I cannot think of right now that would make communication between the BMS and Inverter a better option.

I have attached all my current inverter as well as Seplos BMS settings for your reference. These settings have been working quite well for me.

Hope this helps.

 

[smdl]

Wow! This is fantastic, thanks. Lots of interesting stuff there, for sure. I'll spend some time digesting what your have written, and I'm sure that this will put me miles ahead of where I was.

Cheers,
Shaun

 

[guillaumeB]

In answer to your questions:

1. I use regular ethernet cables to connect my Seplos BMS with the Growatt inverter and they seem to work okay. Some users have reported problems but it could very well be due to different firmware/software versions of either their inverter or the BMS from mine. Some have used the pin mappings provided in the manuals to make custom cables. I have come to realize that due to lack of proper/consistent version release notes from both Growatt and Seplos the issues facing users of their products differ and so do the solutions.

2. I use the BMS port on the inverter to connect to the CAN port on my Seplos BMS and it works fine. Again I use regular ethernet cables. These instructions can be found in both manuals and they work for me.

3. I use the two other RS4851/2 ports on the BMS to connect to my laptop to configure/monitor the BMS. Either can be used. They are also used to connect two BMS's in parallel.

4. I tried both the "USE2" and "L51" battery settings on the Growatt inverter and found the "L51" to be better since it allows for communication between the two for the following reasons:

A. It allows the inverter to read the capacity of the battery in % accurately which allowed me to set the switch from "Battery to Utility"
and "Utility to Battery" accurately (Refer attached "Growatt Inverter Settings 3"). I prefer using remaining capacity as opposed to voltage.

B. It allows the BMS to tell the inverter to vary the charge (Amps) based on the state of the battery (Refer attached "Growatt Inverter
Settings 2").

C. I can also set the "Remaining capacity Alarm/Protection" on the BMS to be higher than the "Battery Voltage Cut-off Point" on
the Inverter since the BMS has the ability to recover once the desired capacity has been reached without manual intervention.

D. I am not completely sure of this since I have not performed any extensive tests but I do believe the Battery BMS is in a better position to
demand "Charge" or "Discharge" status since it knows the complete cellwise state of the battery.

I am sure there are other situations that I cannot think of right now that would make communication between the BMS and Inverter a better option.

I have attached all my current inverter as well as Seplos BMS settings for your reference. These settings have been working quite well for me.

Hope this helps.

Great help! So detailed ?

Have you experienced that the inverter is not keeping the set value for "Battery to Grid"?


My Growatt SPF5000ES is connected to Seplos BMS by CAN on Li51 protocol.

My Battery to Gris value always go back to 50% no matter what I change it to.

 

[diysaa12]

Thanks for your comments. In regards to your question pls check your Seplos BMS "Remaining Capacity Protection" setting per attached image I believe It should always be lower than your Growatt inverter B2AC setting else the BMS will override it.

 

[guillaumeB]

Thanks for your comments. In regards to your question pls check your Seplos BMS "Remaining Capacity Protection" setting per attached image I believe It should always be lower than your Growatt inverter B2AC setting else the BMS will override it.

Wow thanks for your help. This value was already at 5% but I went through all your BMS settings and changed them like yours and now it works, I can set it on the inverter and it sticks!

The only remaining strange thing is that the BMS shows a capacity of 200aH as batteries are 302aH.

 

[diysaa12]

Change the BMS settings number 58 called Battery rated capacity to 302 ah. Let me know if it worked.

 

[guillaumeB]

Change the BMS settings number 58 called Battery rated capacity to 302 ah. Let me know if it worked.

Thanks for the heads up; for a reason I don't know these fields are not editable for me in the parameters.

 

[diysaa12]

Click on login and enter admin and admin for login and pwd. After making the changes click on setall. Review changes carefully before applying them.

 

[guillaumeB]

Click on login and enter admin and admin for login and pwd. After making the changes click on setall. Review changes carefully before applying them.

Alright it did worked! The only number that is still at 200 is the Rated Capacity. Also I notice in your screenshot that at 52.22V you are at almost 40% SOC, how come I am at 10% by 53.74v?

Thanks again, you really are getting me through this!

 

[diysaa12]

Your welcome. My battery is at a lower voltage because it is under discharge versus yours which is under charge, usually the battery records are higher voltage when being charged at least that is my understanding.

 

[leinadw]

3. I use the two other RS4851/2 ports on the BMS to connect to my laptop to configure/monitor the BMS. Either can be used. They are also used to connect two BMS's in parallel.

Hallo,

welchen RS485 to USB Converter hast du benutzt? Hast du einen Link?

Grüße aus Deutschland vom Daniel

 

[diysaa12]

Hallo,

welchen RS485 to USB Converter hast du benutzt? Hast du einen Link?

Grüße aus Deutschland vom Daniel

I use the converter that was supplied by seplos for an extra $20 when I ordered the Mason 280 kit

 

[leinadw]

gelöschtes Posting.

 

[leinadw]

I use the converter that was supplied by seplos for an extra $20 when I ordered the Mason 280 kit

Ok, danke. Den habe ich leider nicht mitbestellt und mir später einen gleich aussehnden bei ebay geholt. Mit dem bekomme ich immer ein Timeout im BatteryMonitor. :-(

 

[leinadw]

B. It allows the BMS to tell the inverter to vary the charge (Amps) based on the state of the battery (Refer attached "Growatt Inverter
Settings 2").

Hey, ich habe 3x SPF5000ES und im Menü 2 werden mir als maximale Ladeleistung für Solar und Netz 33A angezeigt (3x 33A = 100A Ladeleistung gesamt). Kann ich im BMS irgendwie einstellen, dass der Wert pro Wechslerichter höher gesetzt wird? Z.B. 3x 60A = 180A? Ich musste meinen String teilen und auf zwei Wechselrichter aufteilen, um die gesamte Leistung vom PV-Feld abrufen zu können.

 

[Cdohrman]

Hey, ich habe 3x SPF5000ES und im Menü 2 werden mir als maximale Ladeleistung für Solar und Netz 33A angezeigt (3x 33A = 100A Ladeleistung gesamt). Kann ich im BMS irgendwie einstellen, dass der Wert pro Wechslerichter höher gesetzt wird? Z.B. 3x 60A = 180A? Ich musste meinen String teilen und auf zwei Wechselrichter aufteilen, um die gesamte Leistung vom PV-Feld abrufen zu können.

Hello, I'm having the same 3 SPF5000ES installation and applying 60/80 A per inverter in menu 2, which results in a combined charge amperage to the batteries (6 packs of 304 Ah cells) of up to 220 A at peak time (midday).

 

[kosmasan]

I have the same setup. When i set 60amp in menu 2 of growatt, midday it switches back to 33amps. It does not keep the setting