EN 40
YASKAWA ELECTRIC
TOBP C730600 59A V1000 Option Modbus TCP/IP Installation Manual
9 Troubleshooting
9
Troubleshooting
u
Drive-Side Error Codes
Drive-side error codes appear on the drive digital operator. Causes of the errors and
corrective actions are listed in
Table 14
. For additional error codes that may appear on the
drive digital operator, refer to the drive Technical Manual.
n
Faults
Both bUS (Option communication error) and EF0 (External fault input from the option) can
appear as an alarm or as a fault. When a fault occurs, the digital operator ALM LED remains
lit. When an alarm occurs, the ALM LED flashes.
If communication stops while the drive is running, use the following questions as a guide to
help remedy the fault:
• Is the option properly installed?
• Is the communication line properly connected to the option? Is it loose?
• Is the controller program working? Has the controller/PLC CPU stopped?
• Did a momentary power loss interrupt communications?
Table 14 Fault Display and Possible Solutions
LED Operator Display
Fault Name
bUS
Option Communication Error.
• After establishing initial communication, the connection was lost
• Only detected when the run command or frequency reference is assigned to the option
(b1-01 = 3 or b1-02 = 3)
Cause
Possible Solution
Master controller (PLC)
has stopped
communicating
• Check that power is supplied to the PLC
• Check that PLC is not in program mode
Communication cable is
not connected properly
• Check for faulty wiring
• Correct any wiring problems
A data error occurred due
to noise
• Check the various options available to minimize the effects of noise
• Counteract noise in the control circuit, main circuit, and ground wiring
• If a magnetic contactor is identified as a source of noise, install a surge absorber to the
contactor coil
• Make sure the cable used meets the Modbus TCP/IP requirements
• Make sure the option ground wire is connected between option FE terminal and the
drive ground terminal connected to earth ground
Option is damaged
If there are no problems with the wiring and the error continues to occur, replace the
option.
