YASKAWA Z1000 CIMR-ZU*A Series Programming Manual page 120

1.8 L: Protection Functions
n L8-15: oL2 Characteristics Selection at Low Speeds
Selects whether the drive overload capability (oL fault detection level) is reduced at low speeds to prevent premature output
transistor failures. Set this parameter to 0 (Protection disabled at low speed) when protection is activated for an oL2 fault for
a light load at low speed.
Note: 1. Contact Yaskawa before using the drive for applications for which the setting is 0 (disabled).
2. Do not set this parameter to 0 (disabled) in V/f or OLV control.
3. Do not set this parameter to 0 (disabled) in models 4o0302 to 4o0930.
No.
L8-15
Setting 0: oL2 (Drive Overload) Characteristics Disabled at Low Speed
The overload protection level is not reduced. Frequently operating the drive with high output current at low speed can lead to
premature drive faults.
Setting 1: oL2 (Drive Overload) Characteristics Enabled at Low Speed
The overload protection level (oL2 fault detection level) is automatically reduced at speeds below 6 Hz. At zero speed, the
overload is derated by 50%.
n L8-18: Software Current Limit Selection
Enables and disables the Software Current Limit (CLA) protection function to prevent main circuit transistor failures caused
by high current.
Note: Do not change this setting unless absolutely necessary.
No.
L8-18
Setting 0: Software CLA Disabled
The drive may trip on an oC fault if the load is too heavy or the acceleration is too short.
Setting 1: Software CLA Enabled
When the Software CLA current level is reached, the drive reduces the output voltage to reduce the current. Normal operation
continues when the current level drops below the Software CLA level.
n L8-27: Overcurrent Detection Gain
Adjusts the overcurrent detection level in OLV/PM control mode. A setting of 100% is equal to the motor rated current. When
the drive rated current is considerably higher than the motor rated current, use this parameter to decrease the overcurrent level
and prevent motor demagnetization from high current.
Overcurrent detection uses the lower value between the overcurrent level for the drive and the motor rated current multiplied
by L8-27.
No.
L8-27
n L8-29: Current Unbalance Detection (LF2)
Enables or disables output current unbalance detection in OLV/PM control mode. Current unbalance can heat a PM motor
and demagnetize the magnets. The current unbalance detection function monitors output current and triggers the LF2 fault to
prevent such motor damage.
No.
L8-29
Setting 0: Disabled
No current unbalance protection is provided to the motor.
Setting 1: Enabled
The LF2 fault is triggered if an output current unbalance is detected. Drive output shuts off and the motor coasts to stop.
120
Name
oL2 Characteristics Selection at Low Speed
Name
Software Current Limit Selection
Name
Overcurrent Detection Gain
Name
Current Unbalance Detection (LF2)
Setting Range
Setting Range
Setting Range
0.0 to 400.0%
Setting Range
YASKAWA SIEP YAIZ1U 03B YASKAWA AC Drive – Z1000 Programming Manual
Default
0, 1 1
Default
Determined by
0, 1
A1-02
Default
300.0%
Default
0, 1 1