Exceptions And Troubleshooting - Toshiba VF-A7 Instruction Manual

10.9 Exceptions and Troubleshooting

Although by no means exhaustive, Table 6 provides some possible causes behind
some of the most common errors experienced when using the Modbus TCP/IP
interface.
Problem
Register addressing is off by 1
Modbus TCP/IP client cannot establish
communication with the ETH-100
Drive does not respond to network
commands / frequency command
ILLEGAL FUNCTION exception
(Modbus exception code 01)
ILLEGAL DATA ADDRESS exception
(Modbus exception code 02)
ILLEGAL DATA VALUE exception
(Modbus exception code 03)
NEGATIVE ACKNOWLEDGE exception
(Modbus exception code 07)
GATEWAY PATH UNAVAILABLE
exception (Modbus exception code 0A)
GATEWAY TARGET DEVICE FAILED TO
RESPOND exception
(Modbus exception code 0B)
Table 6: Troubleshooting Reference
Refer to Section 10.3 for Modbus/drive mapping
Ensure at least one of the connected drives is powered on
Check that the drive and Ethernet communication cables
are fully seated into their respective communication ports
Check the Ethernet communication parameters (IP
address, etc.)
Check drive's frequency mode and command mode
selection parameters
Where applicable, confirm the values of bits #14 and #15
of communication command word
Confirm that communication frequency command value is
between lower limit and upper limit frequencies
The indicated Modbus function is not supported: refer to section
10.2 for a list of supported functions
The targeted drive register (or one in a group of targeted
registers) does not exist: check the drive's supported register
list
The value written was rejected by the drive as invalid: check the
value and drive setting range
An attempt was made to write to a drive register while the
drive was running that does not accept writes while the
drive is running
An attempt was made to write to a read-only register
Confirm that the drive communication cable is fully seated
into the drive's and ETH-100's communication ports
Confirm that the drive communication cable is not routed
near the drive's input power or motor wiring or any other
electrical noise-producing cables or equipment
Unit Identifier (UI) was invalid: UI must be 1
The targeted drive is not online or failed to respond:
Confirm that the targeted drive is powered-on
Confirm that the drive communication cable is fully seated
into the drive's and ETH-100's communication ports
Confirm that the drive communication cable is not routed
near the drive's input power or motor wiring or any other
electrical noise-producing cables or equipment
34
Possible Cause
3