Yaskawa Z1000 AC Drive HVAC - Manual (Page 202)

Digital Operator Display Fault Name
FbL
PID Feedback Loss
PID feedback loss detection is programmed to trigger a fault (b5-12 = 2 or 5) and the PID feedback level
is below the detection level set to b5-13 for longer than the time set to b5-14.
Cause Possible Solution
Parameters are set inappropriately Check b5-13 and b5-14 settings.
Incorrect PID feedback wiring Correct the wiring.
There is a problem with the feedback sensor
• Check the sensor on the control side.
• Replace the sensor if damaged.
Digital Operator Display Fault Name
GF
Ground Fault
• A current short to ground exceeded 50% of rated current on the output side of the drive.
• Setting L8-09 to 1 enables ground fault detection.
Cause Possible Solution
Motor insulation is damaged
• Check the insulation resistance of the motor.
• Replace the motor.
A damaged motor cable is creating a short
circuit
• Check the motor cable.
• Remove the short circuit and reapply power to the drive
• Check the resistance between the cable and the ground terminal .
• Replace the cable.
Excessive leakage current at the drive output
• Reduce the carrier frequency.
• Reduce the amount of stray capacitance.
The drive started to run during a current offset
fault or while coasting to a stop
• Set b3-01 to 1 to enable Speed Search at Start.
• Perform Speed Search 1 or 2 (H1- = 61 or 62) via one of the external terminals.
Hardware problem
If the problem continues, replace the control board or the entire drive. Contact Yaskawa or a Yaskawa
representative for instructions on replacing the control board.
Digital Operator Display Fault Name
LF
Output Phase Loss
• Phase loss on the output side of the drive.
• Setting L8-07 to 1 or 2 enables Phase Loss Detection.
Cause Possible Solution
The output cable is disconnected
• Check for wiring errors and properly connect the output cable.
• Correct the wiring.
The motor winding is damaged
• Check the resistance between motor lines.
• Replace the motor if the winding is damaged.
The output terminal is loose
• Apply the tightening torque specified in this manual to fasten the terminals. Refer to Main Circuit
Wire Gauges and Tightening Torque on page 81 for details.
The rated current of the motor being used is
less than 5% of the drive rated current
Check the drive and motor capacities.
An output transistor is damaged
If the problem continues, replace the control board or the entire drive. Contact Yaskawa or a Yaskawa
representative for instructions on replacing the control board.
A single-phase motor is being used The drive cannot operate a single phase motor.
Digital Operator Display Fault Name
LF2
Output Current Imbalance
One or more of the phases in the output current are lost.
Cause Possible Solution
Phase loss has occurred on the output side of
the drive
• Check for faulty wiring or poor connections on the output side of the drive.
• Correct the wiring.
Terminal wires are loose on the output side of
the drive
Apply the tightening torque specified in this manual to fasten the terminals. Refer to Main Circuit Wire
Gauges and Tightening Torque on page 81 for details.
The output circuit is damaged
If the problem continues, replace the control board or the entire drive. Contact Yaskawa or a Yaskawa
representative for instructions on replacing the control board.
5.4 Fault Detection
202 YASKAWA ELECTRIC TOEP YAIZ1U 03A YASKAWA AC Drive – Z1000 User Manual