Rctpower Inverter Modbus Register 40032: AC Current (Sum of active phases)

Technical Definition

The register AC Current (Sum of active phases) at address 40032 is used to monitor ac current (sum of active phases) on the Rctpower Inverter.

• Protocol: Modbus RTU
• Data Type: S WORD
• Unit: A
• 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 AC Current (Sum of active phases) (Address: 40032)
# Note: Check if your device uses 0-based or 1-based addressing
result = client.read_input_registers(address=40032, 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: "AC Current (Sum of active phases)"
  address: 40032
  value_type: S_WORD
  unit_of_measurement: "A"

Connection Diagram

Here is the standard RS485 wiring for this configuration:

graph TD
    PLC[Host Controller / Home Assistant]
    Device[Rctpower Inverter]

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

💡 Engineer's Insight

Analysis: Sum of AC currents in active phases in Amperes (A). Indicates total current draw/supply.

Troubleshooting: Zero suggests no current flow, possibly due to open circuits, tripped breakers, or device malfunction. Check circuit integrity.