Code

Name

Causes

Possible Solutions

bUS

Option Communication Error

The communications cable wiring is incorrect.

Correct wiring errors.

There is a short-circuit in the communications cable or the communications cable is not connected.

  • Repair short circuits and connect cables.

  • Replace the defective communications cable.

Electrical interference caused a communication data error.

  • Examine the control circuit lines, main circuit lines, and ground wiring, and decrease the effects of electrical interference.

  • Make sure that a magnetic contactor is not the source of the electrical interference, then use a Surge Protective Device if necessary.

  • Use only the recommended cables or other shielded line. Ground the shield on the controller side or the drive input power side.

  • Separate the communication wiring from drive power lines, and install a noise filter to the input side of the power supply for communication.

  • Decrease the effects of electrical interference from the controller.

The option card is incorrectly installed to the drive.

Correctly install the option card to the drive.

The option card is damaged.

If the alarm continues and the wiring is correct, replace the option card.
Note:

  • The drive detects this error if the Run command or frequency reference is assigned to the option card.

  • If the drive detects this error, the terminal set to H2-01 to H2-03 = 10 [MFDO Function Selection = Alarm] will activate.

  • If the drive detects this error, it will operate the motor as specified by the stopping method set in F6-01 [Communication Error Selection].