Esp32 C3 Zero Epever Modbus Register 12544: PV array input voltage

Technical Definition

The register PV array input voltage at address 12544 is used to monitor pv array input voltage on the Esp32 C3 Zero Epever.

• Protocol: Modbus RTU
• Data Type: U WORD
• Unit: V
• 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 PV array input voltage (Address: 12544)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=12544, 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: "PV array input voltage"
  address: 12544
  value_type: U_WORD
  unit_of_measurement: "V"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

graph TD
    PLC[Host Controller / Home Assistant]
    Device[Esp32 C3 Zero  Epever]

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

💡 Engineer's Insight

Analysis: DC voltage generated by the solar PV array connected to the Epever device. Measured in Volts (V).

Troubleshooting: Zero suggests no sunlight, disconnected panels, faulty wiring, or a device fault. Check panel connections and environmental conditions.