YASKAWA P1000 Technical Manual page 305

Digital Operator Display
Cause
Parameter settings are not appropriate for the
load
Digital Operator Display
Cause
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
Digital Operator Display
Cause
External operator is not properly connected to
the drive
Digital Operator Display
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
Excessive braking load
Surge voltage entering from the drive input
power
Ground fault in the output circuit causes the
DC bus capacitor to overcharge
YASKAWA SIEP YAIP1U 01C AC Drive - P1000 Technical Manual
Overtorque Detection 2
oL4
The current has exceeded the value set for Torque Detection Level 2 (L6-05) for longer than the allowable
time (L6-06).
Check the settings of parameters L6-05 and L6-06.
High Slip Braking oL
oL7
The output frequency stayed constant for longer than the time set to n3-04 during High Slip Braking.
• Reduce deceleration times in parameters C1-02 and C1-04 for applications that do not use High Slip
Braking.
• Use a braking resistor to shorten deceleration time.
• Increase parameter n3-04 (High-slip Braking Overload Time).
• Install a thermal relay and increase the setting of n3-04 to maximum value.
External Digital Operator Connection Fault
The external operator has been disconnected from the drive.
oPr
Note: An oPr fault will occur when all of the following conditions are true:
• 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. Reconnect the operator and reapply drive
input power.
Overvoltage
Voltage in the DC bus has exceeded the overvoltage detection level.
ov
• For 200 V class drives: approximately 410 V
• For 400 V class drives: approximately 820 V (740 V when E1-01 is less than 400)
• For 600 V class drives: approximately 1040 V
• Increase the deceleration time (C1-02 and C1-04).
• Install a dynamic braking resistor or a dynamic braking resistor unit.
• 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.
The braking torque was too high, causing regenerative energy to charge the DC bus. Reduce the braking
torque, use a dynamic braking option, or lengthen decel time.
Install a DC link choke.
Note: Voltage surge can result from a thyristor convertor and phase advancing capacitor using
the same input power supply.
• Check the motor wiring for ground faults.
• Correct grounding shorts and reapply power.
Fault Name
Possible Solution
Fault Name
Possible Solution
Fault Name
Possible Solution
Fault Name
Possible Solution
6.4 Fault Detection
6
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