L3: Stall Prevention - YASKAWA V1000 Series Technical Manual

*3. This value is reset its default setting when the control mode is changed (A1-02). The value shown here is for Open Loop Vector Control.
• This setting rarely needs to be changed.
• Sets the level of voltage suppression in the DC bus when KEB Ride-Thru 2 is operating.
Adjustment to KEB Ride-Thru 2 can be made by changing the gain in the DC bus voltage (L3-20), gain calculations for deceleration (L3-21), inertia
calculations for the motor acceleration time (L3-24), and the load inertia ratio (L3-25). For more information, refer to

L3: Stall Prevention

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"Stalling" occurs when the motor is unable to keep up with the frequency reference, and falls too far behind the normal the amount of slip. This 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.
L3-01: Stall Prevention Selection during Acceleration
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L3-02: Stall Prevention Level during Acceleration
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L3-03: Stall Prevention Limit during Acceleration
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No.
L3-01
L3-02
L3-03
L3-22
*1. Setting range in PM Open Loop Vector is 0 and 1. When enabled, the drive will stop accelerating if the level set to L3-02 is reached, then decelerate briefly for 100 ms. Acceleration begins
again after the current value is restored.
*2. The upper limit is determined by the duty rating and the carrier frequency derating selection (C6-01 and L8-38 respectively).
Overview
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 resulting.
Detailed Description
Setting
0 Disabled: Motor accelerates at active acceleration rate.
General Purpose: When output current exceeds L3-02 level, acceleration stops. Acceleration will continue when the output current level falls below the L3-02
1
level.
2 Intelligent: The active acceleration rate is ignored. Acceleration is completed in the shortest amount of time without exceeding the current value set in L3-02.
• L3-01 = 0
The drive may not be able to perform acceleration within the specified time if the acceleration time setting is too short.
• L3-01 = 1
Enables Stall Prevention during acceleration.
Timechart
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The figure below shows the frequency characteristics when L3-01 is set to 1.
YASKAWA ELECTRIC SIEP C710606 18A YASKAWA AC Drive – V1000 Technical Manual (Preliminary)
Name
Stall Prevention Selection during Acceleration
Stall Prevention Level during Acceleration
Stall Prevention Limit during Acceleration
Deceleration Time at Stall Prevention during Acceleration
Output Current
Stall Prevention level
L3-02
during deceleration
L3-02
-15%
Output Current
Controls the output frequency
to prevent the motor from stalling
Figure 5.73 Timechart for Stall Prevention during Acceleration
Setting Range
0 to 2 *1
*2
0 to 150
0 to 100
0.0 to 6000.0
Description
Time
Time
5.8 L: Protection Functions
L3: Stall Prevention
Default Page
1 −
*2 −
50% −
0.0 s −
191
5