Yaskawa Z1000U - Manual (Page 171)

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.
No. Name Setting Range Default
L8-15 oL2 Characteristics Selection at Low Speed 0, 1 1
Setting 0: Protection 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: Protection 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. Name Setting Range Default
L8-18 Software Current Limit Selection 0, 1 0
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 L8-19: Frequency Reduction Rate during Overheat Pre-Alarm
Specifies the output frequency reduction when L8-03 is set to 4 and an oH alarm is present. Set as a factor of the maximum
output frequency.
No. Name Setting Range Default
L8-19 Frequency Reduction Rate During Overheat Pre-Alarm 10.0 to 100.0% 20.0%
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.
Note: The drive detects the lowest overcurrent from the overcurrent level of the drive, the setting value of this parameter, and the overcurrent
level determined from the motor rated current.
No. Name Setting Range Default
L8-27 Overcurrent Detection Gain 0.0 to 400.0% 300.0%
n L8-29: Current Unbalance Detection (LF2)
Enables and disables output current unbalance detection in OLV/PM. 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. Name Setting Range Default
L8-29 Current Unbalance Detection (LF2) 0, 2 2
4.12 Advanced Drive Setup Adjustments
YASKAWA ELECTRIC TOEP C710636 10B Z1000U HVAC MATRIX Drive User Manual 171
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Start-Up Programming & Operation