Danfoss VLT Series Design Manual page 152

7. RS-485 Installation and Set-up
Function
Diagnostics
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
Exception
data field (decimal)
7
00
01
02
03
04
05
06
07
11
17
18
64
65
66
67
130
131
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.
152
Function Code Sub-function
code
8 1
2
10
11
12
13
14
Modbus RTU Message Framing Structure, Function Field.
code in Exception code description
The parameter number does not exit.
There is no write access to the parameter.
The data value exceeds the parameter limits.
The sub-index in use does not exit.
The parameter is not of the array type.
The data type does not match the parameter called
Only reset
Not changeable
No write access
Data change in the parameter called is not possible in the present
mode.
Other error
Invalid data address
Invalid message length
Invalid data length or value
Invalid function code
There is no bus access to the parameter called
Data change is not possible because factory set-up is selected
MG.11.B4.22 - VLT
Sub-function
Restart communication
Return diagnostic register
Clear counters and diagnostic register
Return bus message count
Return bus communication error count
Return bus exception error count
Return slave message count
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