YASKAWA CIMR-JA Series Installation & Start-Up Manual page 132

5.4 Fault Detection
Ground fault in the output circuit
causing the DC bus capacitor to
overcharge.
Drive input power voltage is too
high.
The dynamic braking transistor is
damaged.
The braking transistor is wired
incorrectly.
Drive fails to operate properly due
to noise interference.
Motor hunting occurs.
LED Operator Display
Cause
There is phase loss in the drive input
power.
There is loose wiring in the drive
input power terminals.
There is excessive fluctuation in the
drive input power voltage.
There is poor balance between
voltage phases.
The main circuit capacitors are
worn.
LED Operator Display
Cause
Deceleration time is too short and
excessive regenerative energy is
flowing back into the drive.
132 YASKAWA ELECTRIC TOEP C710606 25B YASKAWA AC Drive J1000 Installation & Start-Up Manual
• Check the motor wiring for ground faults.
• Correct grounding shorts and turn the power back on.
• Check the voltage.
• Lower drive input power voltage within the limits listed in the specifications.
Replace the drive.
• Check braking transistor wiring for errors.
• Properly rewire the braking resistor device.
• Review the list of possible solutions provided for controlling noise.
• Review the section on handling noise interference and check the control circuit
lines, main circuit lines and ground wiring.
• Adjust the parameters that control hunting.
• Set the hunting prevention gain (n1-02).
Input Phase Loss
PF
Drive input power has an open phase or has a large imbalance of voltage between
phases. Detected when L8-05 = 1 (enabled).
• Check for wiring errors in the main circuit drive input power.
• Correct the wiring.
• Ensure the terminals are tightened properly.
• Apply the tightening torque specified in this manual to fasten the terminals.
Refer to Wire Gauges and Tightening Torque on page 50
• Check the voltage from the drive input power.
• Review the possible solutions for stabilizing the drive input power.
• Disable Input Phase Loss Detection (L8-05 = "0"). PF is detected if DC bus
ripple is too high. If it is disabled, there is no fault but the ripple is still too high,
thereby the capacitors are stressed more and lose lifetime.
• Stabilize drive input power or disable phase loss detection.
• Check the maintenance time for the capacitors (U4-05).
• Replace the drive if U4-05 is greater than 90%.
• Check for anything wrong with the drive input power.
• If nothing is wrong with the drive input power, try the following solutions if
the alarm continues:
• Disable Input Phase Loss Protection selection (L8-05 = "0"). PF is detected if
DC bus ripple is too high. If it is disabled, there is no fault but the ripple is still
too high, thereby the capacitors are stressed more and lose lifetime.
• Replace the drive.
Braking Resistor Overheat
Braking resistor protection was triggered.
Fault detection is enabled when L8-01 = 1 (disabled as a default).
rH
Note: The magnitude of the braking load trips the braking resistor overheat alarm,
NOT the surface temperature. Using the braking resistor more frequently than its
rating trips the alarm even when the braking resistor surface is not very hot.
• Check the load, deceleration time and speed.
• Reduce the load.
• Increase the acceleration and deceleration times (C1-01 through C1-04).
• Replace the braking option with a larger device that can handle the power that
is discharged.
Fault Name
Possible Solution
Fault Name
Possible Solution