Getting response as 32768 when reading holding register

[PrakharPriyesh]

Versions

• Python: 3.6
• OS: Windows
• Pymodbus: 2.2.0
• Modbus Hardware (if used): Energy Meter from schneider

Pymodbus Specific

• Client: rtu - sync

Description

I want to read the register value but in response I am getting 32768

Code and Logs

 # code and logs here.
from pymodbus.client.sync import ModbusSerialClient

client = ModbusSerialClient(method='rtu', port='COM6', baudrate=9600, parity='E')
client.connect()

rr = client.read_holding_registers(43110,1,unit=0x05)
client.read_holding_registers(43076, 2, unit=0x05).registers
client.read_input_registers(32022, 1, unit=0x01).registers
client.write_coils(2048,1,unit=1)

[PrakharPriyesh]

Issue was solved.
Actually the Schneider Energy Meter from which I was reading the frequency data has the register address 43109 and 43110. These two register combined together gave the output as floating point value. So, you need to read both the registers together and convert in the correct Endian representation Therefore the new code working is:

Note:

1. ModScan shows the register address after adding the offset of 40001 to the actual address. So you need to pass address - 1.
2. Do refer to the document of the device from which you are reading the data from.

import struct
from pymodbus.client.sync import ModbusSerialClient
from pymodbus.constants import Endian
from pymodbus.payload import BinaryPayloadDecoder

import logging
logging.basicConfig()
log = logging.getLogger()
log.setLevel(logging.DEBUG)

client = ModbusSerialClient(method='rtu', port='COM6', baudrate=9600, parity='E'
,stopbits=1,bytesize=8)

client.connect()
add = 3110

result = client.read_holding_registers(add-1,2, unit=5)

decoder = BinaryPayloadDecoder.fromRegisters(result.registers,byteorder=Endian.Big,wordorder=Endian.Big)
print(decoder.decode_32bit_float())

result.dict
client.close()