L3: Stall Prevention - YASKAWA E1000 Technical Manual

◆ 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.
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L3-01: Stall Prevention Selection during Acceleration
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
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, thus tripping an overload fault.
Setting 1: Enabled
Enables Stall Prevention during acceleration. Operation varies, depending on the control mode.
• V/f Control:
If the output current rises above the Stall Prevention level set in L3-02, then 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.
Limit during Acceleration on page
Figure 5.72
YASKAWA ELECTRIC SIEP C710616 35D YASKAWA AC Drive E1000 Technical Manual
Name
Stall Prevention Selection during Acceleration
222.
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 5.72 Stall Prevention During Acceleration for Induction Motors
5.8 L: Protection Functions
Setting Range
0 to 2
Refer to L3-03: Stall Prevention
Time
Time
Default
1
5
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