YASKAWA V1000 Technical Manual page 262

6.4 Fault Detection
LED Operator Display
Cause
External operator is not properly connected
to the drive.
LED Operator Display
Cause
Overshoot or undershoot is occurring.
Incorrect PG pulse settings.
Inappropriate parameter settings.
LED Operator Display
Cause
Deceleration time is too short and
regenerative energy flows from the motor
into the drive.
Fast acceleration time causes the motor to
overshoot the speed reference.
Excessive braking load.
Surge voltage entering from the drive input
power.
Ground fault in the output circuit causing the
DC bus capacitor to overcharge.
Improper Setting of Speed Search related
parameters. (Includes Speed Search after a
momentary power loss and after a fault
restart.)
Excessive regeneration when overshoot
occurs after acceleration.
Drive input power voltage is too high.
The dynamic braking transistor is damaged. Replace the drive.
The braking transistor is wired incorrectly.
Drive fails to operate properly due to noise
interference.
Load inertia has been set incorrectly.
262
External Digital Operator Connection Fault
• The external operator has been disconnected from the drive.
Note: An oPr fault will occur when all of the following conditions are true:
oPr
• Output is interrupted when the operator is disconnected (o2-06 = 1).
• The run command is assigned to the operator
(b1-02 = 0 and LOCAL has been selected).
• Check the connection between the operator and the drive.
• Replace the cable if damaged.
• Turn off the drive input power and disconnect the operator. Next reconnect the operator and turn
the drive input power back on.
Overspeed (Simple V/f with PG)
oS
Pulse input (RP) indicates that motor speed feedback exceeded F1-08 setting.
• Adjust the gain by using the pulse train input parameters (H6-02 through H6-05).
• Increase the settings for C5-01 (Speed Control Proportional Gain 1) and reduce C5-02 (Speed
Control Integral Time 1).
Set the H6-02 (Pulse Train Input Scaling) = 100%, the frequency of the PG pulses at maximum motor
speed.
Check the setting for the overspeed detection level and the overspeed detection time (F1-08 and F1-09).
Overvoltage
Voltage in the DC bus has exceeded the overvoltage detection level.
ov
• For 200 V class: approximately 410 V
• For 400 V class: approximately 820 V (740 V when E1-01 is less than 400)
• Increase the deceleration time (C1-02, -04, -06, -08).
• Install a braking resistor or a dynamic braking resistor unit.
• Enable stall prevention during deceleration (L3-04 = "1").
Stall prevention is enabled as the default setting.
• Check if sudden drive acceleration triggers an overvoltage alarm.
• Increase the acceleration time.
• Use longer S-curve acceleration and deceleration times.
The braking torque was too high, causing regenerative energy to charge the DC bus.
Reduce the braking torque, use a braking option, or lengthen decel time.
Install a DC reactor.
Note: Voltage surge can result from thyristor convertor and phase advancing capacitor using same
drive main input power supply.
• Check the motor wiring for ground faults.
• Correct grounding shorts and turn the power back on.
• Check the settings for Speed Search related parameters.
• Enable Speed Search Retry function
(b3-19 greater than or equal to 1 to 10).
• Adjust the current level during Speed Search and the deceleration time (b3-02 and b3-03
respectively).
• Perform Line-to-Line Resistance Auto-Tuning and then enable Speed Estimation Type Speed
Search (b3-24 = 1).
• Enable the Overvoltage Suppression function (L3-11 = 1).
• Lengthen the S-curve at acceleration end.
• Check the voltage.
• Lower drive input power voltage within the limits listed in the specifications.
• 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.
• Check the load inertia settings when using KEB, overvoltage suppression or Stall Prevention during
deceleration.
• Adjust L3-25 (Load Inertia Ratio) in accordance with the load.
Fault Name
Possible Solution
Fault Name
Possible Solution
Fault Name
Possible Solution
YASKAWA ELECTRIC SIEP C710606 16C YASKAWA AC Drive – V1000 Technical Manual