Comunication between ESP32 and Inverter thru RS485 (Pylontech protocol)

[Peta-T]

Hello,
is it possible use different converter device like RS232-TTL to RS485 as replacement for CAN BUS ? or not

` RS485-TTL RS232-TTL CAN BUS
┌──────────┐ ┌─────────┐ ┌─────────┐ ┌──────────┐
│ ││16 23│| | | |
│ JK-BMS ││17 22│| TJA1050 |<---CAN H --->| Inverter |
│ │<----GND--->│ │<----GND---->| CAN |<---CAN L --->| |
│ │ 3.3V ---->│ ESP32 │<----5V----->| | | |
└──────────┘ └─────────┘ └─────────┘ └──────────┘

`
Thanks

[Uksa007]

Hi,

I'm guessing you are wanting to communicate with the inverter using RS485?

What make and model inverter do you have?

It's something that I'm working on, it's a totally different protocol, and hardware interface needed:
see here for more info #27

[Peta-T]

Hello, thanks for your answer. My inverter is ISolar-SMX-II-5,6 Bms JK-B2A24S15P This inverter can connect battery only with voltage monitoring  but can also comunicate thru Pylontech RS485 it would be better. I found some protocol description. [PYLON LFP Battery communication protocol - RS485 V2.8 20161216.pdf](https://github.com/Uksa007/esphome-jk-bms-can/files/12615900/PYLON.LFP.Battery.communication.protocol.-.RS485.V2.8.20161216.pdf)

[Uksa007]

The manual doesn't give any info about what Battery protocols it supports it just says this:
"RS485 communication with lithium battery BMS can be conducted directly through this port RS485-2 (need to be customized);"
Manual I found here: https://drive.google.com/file/d/15ojlTx5_jxZ-ZJWstuBDKmq7spnvKwoj/view

need to be customized = pay them when ordering many thousands of units and they can make it work with your supplied protocol.

Unless you have more info from the supplier that details what Battery protocols it supports, it doesn't look very likely it would work with Pylon RS485.

[Uksa007]

This doesn't look too good, that they can't make it work with a real pylon battery?
https://diysolarforum.com/threads/easun-isolar-smx-ii-5-6kp-pylontech-us3000c-bms-comm-error.55403/

[Peta-T]

There is page from my manual

[Peta-T]

And I am able to set this option in inveter setup

[Peta-T]

Ok, thak you very much.It is wrong information, but if I know before any work its good for me.Thanks But I have another question. Is it some way to change your program to set some bit when battery is charged more than for example 70% ?Thanks

[Uksa007]

Why is it wrong information?
Can you please supply a link to your manual or information that says it supports pylon rs485?

What bit do you want set, and why?

[Peta-T]

I had Idea to connect my baterie with inverter, but if is not possible it is wrong.
Unfortunetly My inverter work without this connection.

On My inverter is possible in menu set several options of batteries and one is PYL and I will send you information from my manual.

I have idea to connect some heating when my system have enought energy (for examle 70 or 80% is enought).

Thanks

[Uksa007]

Please see existing discussion re RS485 communication

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