0x81A2

The request by the master is invalid, e. g. invalid CRC checksum, non-supported function code, or impermissible data access.

Modbus: incorrect request by master

Check request by the master:

• Value in the valid range?
• Function code valid?
• No impermissible write access? (e. g. with regard to read-only parameters)

Warning The inverter (slave) responds to the master with an error code:

• 0x01 = invalid function code
• 0x02 = invalid data address
• 0x03 = invalid data value
• 0x04 = slave device failure