L3: Stall Prevention - YASKAWA Z1000 CIMR-ZU*A Series Programming Manual

1.8 L: Protection Functions
Amount of reduction = Slip frequency prior to KEB × (L2-08/100) × 2
No.
L2-08
n L2-10: KEB Detection Time (Minimum KEB Time)
Determines the duration of KEB Ride-Thru operation after it is triggered.
No.
L2-10
n L2-11: DC Bus Voltage Setpoint during KEB
Determines the setpoint (target value) for the DC bus voltage during Single KEB Ride-Thru 2. For Single KEB Ride-Thru 1
and System KEB Ride-Thru, parameter L2-11 defines the voltage level to end KEB Ride-Thru.
No.
L2-11
n L2-29: KEB Method Selection
Selects the way the Kinetic Energy Buffering function operates.
Note: If a multi function input is set for Single KEB Ride-Thru 2 (H1-oo = 7A, 7B), the setting of L2-29 is disregarded and the KEB mode equal
to L2-29 = 1 is automatically selected.
No.
L2-29
Setting 0: Single Drive KEB Ride-Thru 1
Setting 1: Single Drive KEB Ride-Thru 2
u

L3: Stall Prevention

The motor may experience excessive slip because it cannot keep up with the frequency reference when the load is too high or
acceleration and deceleration times are too short. If the motor slips during acceleration, it usually causes an overcurrent fault
(oC), drive overload (oL2), or motor overload (oL1). If the motor slips during deceleration, it can cause excessive regenerative
power to flow back into the DC bus capacitors, and eventually cause the drive to fault out from overvoltage (ov). The Stall
Prevention Function prevents the motor from stalling and while allowing the motor to reach the desired speed without requiring
the user to change the acceleration or deceleration time settings. The Stall Prevention function can be set separately for
acceleration, operating at constant speeds, and deceleration.
n L3-01: Stall Prevention Selection during Acceleration
Stall Prevention during acceleration prevents tripping with overcurrent (oC), motor overload (oL1), or drive overload (oL2)
faults common when accelerating with heavy loads or short acceleration times.
L3-01 determines the type of Stall prevention the drive should use during acceleration.
No.
L3-01
<1> Setting 2 is not available for OLV/PM.
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, causing an overload fault.
Setting 1: Enabled
Enables Stall Prevention during acceleration. Operation varies depending on the control mode.
• V/f Control:
Acceleration is reduced when the output current value exceeds 85% of the level set to parameter L3-02 for a longer than the
time set to L3-27. The acceleration stops when the current exceeds L3-02. Acceleration continues when the current falls
below L3-02 for longer than the time set to L3-27.
104
Name
Frequency Gain at KEB Start
Name
KEB Detection Time
Name
DC Bus Voltage Setpoint during KEB
Name
KEB Method Selection
Name
Stall Prevention Selection during Acceleration
Setting Range
0 to 300%
Setting Range
0 to 2000 ms
Setting Range
431.3 to 1150 Vdc
Setting Range
Setting Range
0 to 2
YASKAWA SIEP YAIZ1U 03B YASKAWA AC Drive – Z1000 Programming Manual
Default
100%
Default
50 ms
Default
Determined by
E1-01
Default
0, 1 0
Default
<1> 1