5.8 L: Protection Functions
190
YASKAWA ELECTRIC
SIEP C710606 44B YASKAWA AC Drive T1000V Technical Manual
■
L2-04: Momentary Power Loss Voltage Recovery Ramp Time
Sets the time constant used to ramp up the voltage during Speed Search. The setting value determines the time for a
change from zero to the maximum voltage.
■
L2-05: Undervoltage Detection Level (Uv1)
Determines the voltage at which a Uv1 fault is triggered.
This setting rarely needs to be changed.
When setting L2-05 is lower than the default setting, be sure to install an AC reactor option to the input side of the power
supply to prevent damage to drive circuitry.
◆
L3: Stall Prevention
When the load is too high or acceleration and deceleration times are too short, the motor may be unable to keep up with
the frequency reference, resulting in excessive slip. This “stalling” makes it impossible to decelerate or accelerate. The
drive can prevent the motor from stalling and still reach the desired speed without the user needing to change the
acceleration or deceleration time settings. The Stall Prevention function can be set separately for acceleration, operating
at constant speeds, and deceleration.
■
L3-01: Stall Prevention Selection during Acceleration
Stall Prevention during acceleration is used when the motor loses speed during acceleration due to a relatively large load.
It prevents overcurrent and motor overload (oL1) from occurring.
This parameter sets the Stall Prevention method for acceleration.
Setting 0: Disabled
No Stall Prevention is provided. If the acceleration time setting is too short, the drive may not be able to accelerate within
the set time and the motor may stall.
Setting 1: Enabled
Enables Stall Prevention during acceleration. The operation depends on the selected control mode.
• V/f or Open Loop Vector Control:
When the output current exceeds 85% of the level set in parameter L3-02, the acceleration rate is reduced. The
acceleration is stopped when the current exceeds L3-02. Acceleration continues when the current falls below L3-02.
The Stall Prevention level is automatically reduced in the field weakening area.
Refer to L3-03: Stall Prevention Limit
during Acceleration on page 192
.
No.
Name
Setting Range
Default
L2-04
Momentary Power Loss Voltage Recovery Ramp Time
0.0 to 5.0 s
Determined by
o2-04 and C6-01
No.
<1> Values are for 200 V class drives and must be doubled for 400 V class drives.
<2> This value is initialized when E1-01 is changed.
Name
Setting Range
Default
Undervoltage Detection Level
150 to 210 V
Determined by
o2-04
No.
<1> Setting 2 is not available for PM OLV.
Name
Setting Range
Default
L3-01
Stall Prevention Selection during Acceleration
0 to 2
1
