Yaskawa AC Drive Z1000 Bypass Technical Manual User Manual
Page 240

Controller is not sending data soon enough to stop
the timeout.
Verify the scan rate in the controller that is communicating with the bypass controller is proper. Adjust
as necessary.
HOA Keypad Display
Minor Fault Name
AL16
<1>
Input Phase Rotation
Cause
Possible Solution
Incorrect phase rotation while Z1-52 is set to 1 in
Bypass Mode.
Check the sequence (phase rotation) of the input wiring to the bypass package.
<1> Available in bypass controller software versions VST800298 and later.
HOA Keypad Display
Minor Fault Name
bb
Baseblock
Drive output interrupted as indicated by an external baseblock signal.
Cause
Possible Solutions
External baseblock signal was entered via one of
the multi-function input terminals (S1 to S7)
Check external sequence and baseblock signal input timing.
Connection is broken or master controller stopped
communicating
• Check for faulty wiring.
• Correct the wiring.
• Check for disconnected cables and short circuits. Repair as needed.
HOA Keypad Display
Minor Fault Name
bUS
Option Communication Error
• The connection was lost after initial communication was established.
• Assign a Run command frequency reference to the option.
Cause
Possible Solutions
Connection is broken or master controller stopped
communicating
• Check for faulty wiring.
• Correct the wiring.
• Check for disconnected cables and short circuits. Repair as needed.
Option is damaged
If there are no problems with the wiring and the fault continues to occur, replace the option.
The option is not properly connected to the drive
• The connector pins on the option are not properly lined up with the connector pins on the drive.
• Reinstall the option.
A data error occurred due to noise
• Check options available to minimize the effects of noise.
• Take steps to counteract noise in the control circuit wiring, main circuit lines and ground wiring.
• Try to reduce noise on the controller side.
• Use surge absorbers on magnetic contactors or other equipment causing the disturbance.
• Use recommended cables or some other type of shielded line. Ground the shield to the controller
side or on the input power side.
• Separate the wiring for communication devices from the drive input power lines.
HOA Keypad Display
Minor Fault Name
CALL
Serial Communication Transmission Error
Communication has not yet been established.
Cause
Possible Solutions
Communications wiring is faulty, there is a short
circuit, or something is not connected properly
• Check for wiring errors.
• Correct the wiring.
• Check for disconnected cables and short circuits. Repair as needed.
Programming error on the master side
Check communications at start-up and correct programming errors.
Communications circuitry is damaged
• Perform a self-diagnostics check.
• If the problem continues, replace either the control board or the entire drive. For instructions on
replacing the control board, contact Yaskawa or your nearest sales representative.
Termination resistor setting is incorrect
Install a termination resistor at both ends of a communication line. Set the internal termination resistor
switch correctly on slave drives. Place DIP switch S2 to the ON position.
HOA Keypad Display
Minor Fault Name
CE
MEMOBUS/Modbus Communication Error
Control data was not received correctly for two seconds.
Cause
Possible Solutions
6.5 Alarm Detection
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YASKAWA ELECTRIC SIEP YAIZ1B 01D YASKAWA AC Drive – Z1000 Bypass Technical Manual