Modbus interface diagnosis
Diagnosis information is locally displayed using LEDs located on the front side of the Modbus interface.
LED Bus (red, green)
LED DD (red, green)
Meaning
Off
Off
Power Supply missing
Green flashing
- Connection to master missing
- Bus address of UMC different form the one configured in the
master
- I/O size mismatch between device and master
Red flashing
Parameter mismatch between device and master
Red
Communication lost, supervision timeout time exceeded
Green
OK, normal data exchange
Amber flashing
Amber flashing
Initializing
Green flashing
Waiting for communication from UMC
Green
OK, normal data exchange
Red flashing
Connection to UMC lost
Red
Internal fault. Replace communication interface.
Modbus exception codes
Code
Name
Meaning
01
ILLEGAL FUNCTION
The function code received in the request is not an allowable action for the slave. It could also indicate
that the slave is in the wrong state to process a request of this type, for example because it is not
configured
02
ILLEGAL DATA ADDRESS
The data address received in the request is not an allowable address for the slave.
03
ILLEGAL DATA VALUE
A value contained in the request data field is not an allowable value for slave. This indicates a fault in
the structure of the remainder of a complex request, such as that the implied length is incorrect.
04
SLAVE DEVICE FAILURE
An unrecoverable error occurred while the slave was attempting to perform the requested action.
- Wrong configuration
- Not supported baud rate
- Serial device connected, but parallel device addressed
- Parallel device connected, but serial device addressed
- Connected serial device defective
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U N I V ER S A L M OTO R CO N T R O L L ER U M C 10 0. 3 |
M R P31 .0 MODBUS TCP COM M U N I C ATI ON MODU LE M A N UA L
