[Python] Able to read data via modscan and using pymodbus on windows but not using pymodbus on...

I am using modbus RTU to read an MFM meter (WL4440 from LnT). I furst tested it using modscan and it is giving correct result :

Modscan result

However, when using pymodbus (on windows) I am getting zero in register 40140 and 40141 (the value should be non zero as per modscan). I turned on logging in pymodbus script and am getting the following result (the logs were too big, so uploaded a text file on drive):

pymodbus debug logs

On the other when trying with pymodbus on rpi I'm getting the following response :

> gridinsight@GI-ED-01:~/edge_device $ bin/python main_read.py
True
DEBUGymodbus.logging:Current transaction state - IDLE
DEBUGymodbus.logging:Running transaction 0
DEBUGymodbus.logging:SEND: 0x1 0x3 0x9c 0xcd 0x0 0x1 0x3b 0xa5
DEBUGymodbus.logging:New Transaction state "SENDING"
DEBUGymodbus.logging:Changing transaction state from "SENDING" to "WAITING FOR REPLY"
DEBUGymodbus.logging:Changing transaction state from "WAITING FOR REPLY" to
"PROCESSING REPLY"
DEBUGymodbus.logging:RECV: 0x1 0x3 0x2 0x0 0x0 0x0 0x0
DEBUGymodbus.loggingrocessing: 0x1 0x3 0x2 0x0 0x0 0x0 0x0
DEBUGymodbus.logging:Frame check failed, ignoring!!
DEBUGymodbus.logging:Frame check failed, ignoring!!
DEBUGymodbus.logging:Short frame: 0x1 0x3 0x2 0x0 0x0 0x0 0x0 wait for more data
DEBUGymodbus.loggingrocessing: 0x0 0x0 0x0
DEBUGymodbus.logging:Short frame: 0x0 0x0 0x0 wait for more data
DEBUGymodbus.logging:Getting transaction 0
DEBUGymodbus.logging:Changing transaction state from "PROCESSING REPLY" to
"TRANSACTION_COMPLETE"
Modbus Error: [Input/Output] No Response received from the remote slave/Unable to
decode response
gridinsight@GI-ED-01:~/edge_device $


Python code on windows :

from pymodbus import framer
import logging
import logging.handlers as Handlers
logging.basicConfig()
log = logging.getLogger()
log.setLevel(logging.DEBUG)
from pymodbus.client import ModbusSerialClient


ip='192.168.1.25'
port = 1502
slave_id=1

#rtu_port = '/dev/serial/by-id/usb-1a86_USB_Serial-if00-port0'
rtu_port = 'COM5'


rtu_client =
ModbusSerialClient(port=rtu_port,framer=framer.FramerType.RTU,baudrate=9600,
timeout=3,parity='E',stopbits=1,handle_local_echo=False)
print(rtu_client.connect())

read_Data =rtu_client.read_holding_registers(address=40141,count=1,slave=1)
print(read_Data.registers)
rtu_client.close()


I used the same python code with a growwatt solar inverter and there it is working perfectly fine.

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