Exception Responses; Exception Codes - BONFIGLIOLI Vectron ACTIVE Manual

6.5 Exception Responses

When the master device sends a request to the inverter it expects a normal re-
sponse. One of four possible events can occur from the master's query:
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The exception response message has two fields that differentiate it from a normal
response:
Function Code Field:
In a normal response, the inverter echoes the function code of the original request
in the function code field of the response. All function codes have a most–significant
bit (MSB) of 0 (their values are all below 0x80 hexadecimal). In an exception re-
sponse, the inverter sets the MSB of the function code to 1. This makes the function
code value in an exception response exactly 0x80 hexadecimal higher than the value
would be for a normal response. With the function code's MSB set, the master can
recognize the exception response and can examine the data field for the exception
code.
Data Field:
In a normal response, the inverter may return data or statistics in the data field (any
information that was requested in the request). In an exception response, the in-
verter returns an exception code in the data field. This defines the server condition
that caused the exception.
The Exception Codes generated by the inverter are listed below

6.6 Exception Codes

The following exception codes are generated by the inverter.
Code
1
2
3
4
05/08
05/08
If the inverter receives the request without a communication error and can han-
dle the query normally, it returns a normal response.
If the inverter does not receive the request due to a communication error, no
response is returned. The master will eventually process a timeout condition for
the request.
If the inverter receives the request, but detects a communication error (parity,
LRC, CRC, ...), no response is returned. The master will eventually process a
timeout condition for the request.
If the inverter receives the request without a communication error, but cannot
handle it (for example, if the request is to read an unknown parameter, the in-
verter will return an exception response informing the client of the nature of the
error.
Modbus Name
ILLEGAL FUNCTION
ILLEGAL DATA ADDRESS
ILLEGAL DATA VALUE
SLAVE DEVICE FAILURE
Modbus Instruction manual
Modbus Instruction manual
Cases when generated by the Inverter
• Function Code unknown
Subfunction Code unknown (Diagnostics Function)
•
No. of Registers field incorrect (must always be 0x01)
•
• Unknown Parameter or Parameter Data Type mismatch
• Error in dataset of frame
No. of bytes too small or too large
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- Certain fields not set to specific values
Read or Write Parameter failed
•
The reason for the error can be obtained by reading out
VABus SST Error Register
Parameter
page).
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