7.8.11. Exception Codes
In the event of an error, the following exception codes may appear in the data field of a response
message. For a full explanation of the structure of an exception (i.e. error) response, please refer
to the section
Modbus RTU Message Framing Structure, Function Field.
Exception code in
data field (decimal)
Exception code description
00
The parameter number does not exit
01
There is no write access to the parameter
02
The data value exceeds the parameter limits
03
The sub-index in use does not exit
04
The parameter is not of the array type
05
The data type does not match the parameter called
06
Only reset
07
Not changeable
11
No write access
17
Data change in the parameter called is not possible in the present
mode
18
Other error
64
Invalid data address
65
Invalid message length
66
Invalid data length or value
67
Invalid function code
130
There is no bus access to the parameter called
131
Data change is not possible because factory set-up is selected
7.9. How to Access Parameters
7.9.1. Parameter Handling
The PNU (Parameter Number) is translated from the register address contained in the Modbus
read or write message. The parameter number is translated to Modbus as (10 x parameter num-
ber) DECIMAL.
7.9.2. Storage of Data
The Coil 65 decimal determines whether data written to the frequency converter are stored in
EEPROM and RAM (coil 65 = 1) or only in RAM (coil 65 = 0).
7.9.3. IND
The array index is set in Holding Register 9 and used when accessing array parameters.
7.9.4. Text Blocks
Parameters stored as text strings are accessed in the same way as the other parameters. The
maximum text block size is 20 characters. If a read request for a parameter is for more characters
than the parameter stores, the response is truncated. If the read request for a parameter is for
fewer characters than the parameter stores, the response is space filled.
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7. RS-485 Installation and Set-up
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