Em340 Package Modbus Register 51: modbus controller name Hz
Technical documentation for Modbus register 51 on Em340 Package. Data type: S WORD. Includes Python and YAML configuration examples.
January 16, 2026
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1 min read
Technical Definition
The register modbus controller name Hz at address 51 is used to monitor modbus controller name hz on the Em340 Package.
- Protocol: Modbus RTU
- Data Type: S WORD
- Unit: Hz
- Access: Read Only
How to Read (Python pymodbus)
Use this code snippet to read this specific value via RS485:
from pymodbus.client.sync import ModbusSerialClient
client = ModbusSerialClient(method='rtu', port='/dev/ttyUSB0', baudrate=9600)
client.connect()
# Read modbus_controller_name Hz (Address: 51)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=51, count=2, unit=1)
if not result.isError():
print(f"Raw Value: {result.registers}")
else:
print("Error reading register")
client.close()
Integration (Home Assistant)
Paste this into your configuration.yaml:
- platform: modbus_controller
name: "modbus_controller_name Hz"
address: 51
value_type: S_WORD
unit_of_measurement: "Hz"
Connection Diagram
Here is the standard RS485 wiring for this configuration:
graph TD
PLC[Host Controller / Home Assistant]
Device[Em340 Package]
PLC -- "A+ (D+)" --> Device
PLC -- "B- (D-)" --> Device
PLC -- GND --> Device
💡 Engineer's Insight
Analysis: System frequency in Hertz (Hz). Standard frequency is 50 or 60 Hz. Indicates grid stability.
Troubleshooting: Zero or abnormal frequency suggests a grid issue or meter malfunction. Check power source and meter status.