Growatt SPF5000ES Offgrid 9kw DIY Solar Project

[Pink7]

14 minutes ago, lom said:

^ Yes, any supported battery that doesn't have BMS communication but I guess you have BMS comms.

 

^^ BMS continuously tells inverter about the SOC so the inverter will know when it is at 100%. If BMS wants to balance batteries then it can request a lower voltage from the inverter.

No I do not have any communication between BMS and Inverter. Im reading myself up on this issue I have and see other with some of same issue.

 

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[lom]

28 minutes ago, Pink7 said:

No I do not have any communication between BMS and Inverter.

That explains it but why don't you let the BMS manage the battery? It does that so much better than an inverter.

 

Edited August 9 by lom

[Pink7]

5 minutes ago, lom said:

That explains it but why don't you let the BMS manage the battery? It does that so much better than an inverter.

 

Well the BMS does manage the battery in normal situation. Just to be clear so no misunderstanding: communication vs no communication in this case is related to use com port on Inverter with a compatible BMS and battery not just voltage per cell as ordinary BMS setup ( as I have) Here is more on the issue

 

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[Pink7]

Today my units started charge as normal after i change: 05 Battery type from "Use2" (who Growatt want its user to use) to "Use" who much user say better to use. Use2 have a complicated way to try manage parts of the charge... This is a quite common issue for Growatt and some similare inverters. Create issues like Inverter not start to charge or stop to charge. Who wants details on this just google: "Growatt - Odd behavior"

 

 

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[Pink7]

Today I got the highest watt value since my build went up 11 months or so ago: 7624Watt. I also noticed the current to be 20A on the one inverter  who also highest i seen. My Growatt 500ESP are supposed to have limit on 22A from earlier 18A.

 

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[Pink7]

Got a advice and help to check my BMS settings today since my inverters sometimes not complete the charge: Found out that i should not use same max charge current settings on inverter and BMS. So I adjusted some down on inverter and some up on BMS charge current limit ( My system log show some: charge over current protection) So lets hope that solved that issue. It should because times in log corresponded with my issues.

 

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[Pink7]

Today its 1 years since i got my solar setup up and working. My solar production for that year is 9,435 KWH so that should be around  B38.7K saved on electric bill if 1 unit is B4.1. My average bill is  B1xx per month. 13% of the cost of the setup back after first 12 months. If use same rates ROI  will take 7.5-8 year.

 

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