YASKAWA P1000 Technical Manual page 201

HOA Keypad Display
Excessive load inertia
Motor is driven by the load
Something on the load side is restricting
deceleration
The overload time during High Slip Braking is too
short
HOA Keypad Display
oPr
Cause
External operator is not properly connected to the
drive
HOA Keypad Display
ov
Cause
Deceleration time is too short and regenerative
energy is flowing from the motor into the drive
Fast acceleration time causes the motor to
overshoot the speed reference
Ground fault in the output circuit causes the DC
bus capacitor to overcharge
Improper parameters related to Speed Search
(including Speed Search after a momentary power
loss and after a fault restart)
Drive input power voltage is too high
Drive fails to operate properly due to noise
interference
Load inertia is set incorrectly
Motor hunting occurs
HOA Keypad Display
ov2
Cause
YASKAWA SIEP YAIP1B 01B YASKAWA AC Drive – P1000 Bypass Technical Manual
Reduce deceleration time in parameter C1-02 for applications that do not use High Slip Braking.
• Increase parameter n3-04 (High-slip Braking Overload Time).
• Install a thermal relay and increase the setting of n3-04 to maximum value.
HOA Keypad Connection Fault
The HOA keypad has been disconnected from the drive.
Note: An oPr fault will occur when The Run command is assigned to the keypad (Z1-07 = 0
and OFF mode 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. Reconnect the operator and reapply
drive input power.
Overvoltage
Voltage in the DC bus has exceeded the overvoltage detection level.
• For 208 V Bypass Drives: approximately 410 V
• For 480 V Bypass Drives: approximately 820 V (740 V when E1-01 is less than 400)
• Increase the deceleration time (C1-02).
• Set L3-04 to 1 to enable stall prevention during deceleration. 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.
• Enable the Overvoltage Suppression function (L3-11 = 1).
• Lengthen the S-curve at acceleration end.
• Check the motor wiring for ground faults.
• Correct grounding shorts and reapply power.
• Check the settings for Speed Search-related parameters.
• Enable Speed Search restart 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 Stationary Auto-Tuning for line-to-line resistance and then set b3-14 to 1 to enable Speed
Estimation Speed Search.
• Check the voltage.
• Lower drive input power voltage within the limits listed in the specifications.
• Review the list of possible solutions provided for controlling noise.
• Review the section on handling noise interference on page
main circuit lines, and ground wiring.
• Check the load inertia settings when using KEB, overvoltage suppression, or Stall Prevention
during deceleration.
• Adjust the load inertia ratio in L3-25 to better match the load.
• Adjust the parameters that control hunting.
• Set the gain for Hunting Prevention (n1-02).
Overvoltage 2
Bus voltage is boosted because the motor cable is too long.
6.4 Fault Detection
Fault Name
Fault Name
Possible Solution
Fault Name
Possible Solution
223 and check the control circuit lines,
Fault Name
Possible Solution
6
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