YASKAWA FSDrive-MV1000 Parameter Manual page 206

2.8 L: Protection Functions
u 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. During acceleration, this usually causes an overcurrent fault (OC),
drive overload (oL2), or motor overload (oL1). During deceleration, it can cause excessive regenerative power to flow
back into the DC bus capacitors, eventually causing the drive to fault out from overvoltage (OV). 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
n
Stall Prevention during acceleration (L3-01) prevents tripping with overcurrent (OC), motor overload (oL1), or drive
overload (oL2) faults common when accelerating with heavy loads.
L3-01 determines the type of Stall Prevention the drive should used during acceleration.
No.
L3-01 Stall Prevention during Acceleration Selection
Setting 0: Disabled
No Stall Prevention is provided. If the acceleration time is too short, the drive may not be able to get the motor up to
speed fast enough, which will trip an overload fault.
Setting 1: Enabled
Enables Stall Prevention during acceleration. Operation varies, depending on the control mode.
V/f Control and Open Loop Vector Control:
If the output current rises above the Stall Prevention level set in L3-02, the drive stops accelerating. Acceleration will not
resume until the output current falls 15% below the setting in L3-02.
The Stall Prevention level is automatically reduced in the constant power range. Refer to
during Acceleration on page
Figure 2.73
Setting 2: Intelligent Stall Prevention
When L3-02 = 2, the drive will disregard the selected acceleration time and try to accelerate in the minimum time. The
acceleration rate is adjusted so that the current does not exceed the value set in parameter L3-02.
206
Name
207.
Output current
Stall Prevention Level
During Acceleration
L3-02
L3-02
-15%
Output frequency
Controls the output frequency
to prevent the motor from stalling
Figure 2.73 Stall Prevention during Acceleration for Induction Motors
Setting Range
0 to 2
YASKAWA ELECTRIC TOEP C710687 03B FSDrive-MV1000 Parameter Guide
Default
1
L3-03: Stall Prevention Limit
Time
Time