PWE low (Hex) Fault Report0 The parameter number used does not exit.1 There is no write access to the defined parameter.2 Data value exceeds the parameter's limits.3 The sub index used does not exit.4 The parameter is not the array type.5 The data type does not match the defined parameter.11 Data change in the defined parameter is not possible in the adjustable frequency drive's present mode. Certainparameters can only be changed when the motor is turned off.82 There is no bus access to the defined parameter.83 Data change is not possible because the factory set-up is selected.7.4.8 Parameter Number (PNU)Bits no. 0-11 transfer parameter numbers. The function of the relevant parameter is defined in the parameter description in the Programming Guide.7.4.9 Index (IND)The index is used together with the parameter number to read/write-access parameters with an index, e.g., par. 15-30Fault Log: Error Code. The indexconsists of 2 bytes, a low byte and a high byte.Only the low byte is used as an index.7.4.10 Parameter Value (PWE)The parameter value block consists of 2 words (4 bytes), and the value depends on the defined command (AK). The master prompts for a parametervalue when the PWE block contains no value. To change a parameter value (write), write the new value in the PWE block and send from the master tothe slave.When a slave responds to a parameter request (read command), the present parameter value in the PWE block is transferred and returned to the master.If a parameter contains not a numerical value but several data options, e.g., par. 0-01Language where [0] corresponds to English, and [4] correspondsto Danish, select the data value by entering the value in the PWE block. See Example - Selecting a data value. Serial communication is only capable ofreading parameters containing data type 9 (text string).Par. 15-40FC Type to par. 15-53Power Card Serial Number contain data type 9.For example, read the unit size and AC line voltage range in par. 15-40FC Type. When a text string is transferred (read), the length of the message isvariable, and the texts are of different lengths. The message length is defined in the second byte of the message, LGE. When using text transfer theindex character indicates whether it is a read or a write command.To read a text via the PWE block, set the parameter command (AK) to ’F’ Hex. The index character high-byte must be “4”.Some parameters contain text that can be written to via the serial bus. To write a text via the PWE block, set the parameter command (AK) to ’F’ Hex.The index characters high-byte must be “5”.VLT AQUA Low Harmonic Drive InstructionManual 7 RS-485 Installation and Set-upMG.20.T1.22 - VLT® is a registered Danfoss trademark 7-97