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Renogy Modbus1 Modbus Register 273: $locationName $device1Name Charged Current Today

Technical documentation for Modbus register 273 on Renogy Modbus1. Data type: U WORD. Includes Python and YAML configuration examples.

January 16, 2026 1 min read

Technical Definition

The register $locationName $device1Name Charged Current Today at address 273 is used to monitor $locationname $device1name charged current today on the Renogy Modbus1.

  • Protocol: Modbus RTU
  • Data Type: U WORD
  • Unit: AH
  • 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 $locationName $device1Name Charged Current Today (Address: 273)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=273, 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: "$locationName $device1Name Charged Current Today"
  address: 273
  value_type: U_WORD
  unit_of_measurement: "AH"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

graph TD
    PLC[Host Controller / Home Assistant]
    Device[Renogy Modbus1]

    PLC -- "A+ (D+)" --> Device
    PLC -- "B- (D-)" --> Device
    PLC -- GND --> Device


💡 Engineer's Insight

Analysis: The total current used for charging today. Units: Ampere-hours (Ah).

Troubleshooting: Zero value indicates no charge accumulation. Check charging source, battery acceptance, and controller configuration.