Parameter Details
12
12.9 L: Protection Functions
YASKAWA SIEPC71061705H GA700 Series Technical Manual 893
• L2-29 = 1 [Kinetic Energy Backup Method = Single Drive KEB Ride-Thru 2]
• L3-04 = 2 [Stall Prevention during Decel = Intelligent (Ignore Decel Ramp)]
• L3-11 = 1 [Overvoltage Suppression Select = Enabled]
• H1-xx = 7A or 7B [MFDI Function Selection = KEB Ride-Thru 2 Activate (N.O./N.C.)]
Note:
• If stall prevention during deceleration function causes ov [Overvoltage] and Uv1 [DC Bus Undervoltage] faults when you start
deceleration and L2-29 = 1, H1-xx = 7A or 7B, or L3-04 = 2, gradually increase this parameter in 0.1-unit increments. If the setting
value is too high, it can cause large speed or current ripples.
• If sudden increases in the regenerative load cause ov faults and L3-11 = 1, gradually increase this parameter in 0.1-unit increments. If
the setting value is too high, it can cause large speed or current ripples.
■ L3-21: OVSuppression Accel/Decel P Gain
No.
(Hex.)
Name Description
Default
(Range)
L3-21
(0466)
Expert
OVSuppression Accel/
Decel P Gain
Sets the proportional gain to calculate acceleration and deceleration rates.
Determined by A1-02
(0.10 - 10.00)
Set one of these parameters to enable L3-20:
• L2-29 = 1 [Kinetic Energy Backup Method = Single Drive KEB Ride-Thru 2]
• L3-04 = 2 [Stall Prevention during Decel = Intelligent (Ignore Decel Ramp)]
• L3-11 = 1 [Overvoltage Suppression Select = Enabled]
• H1-xx = 7A or 7B [MFDI Function Selection = KEB Ride-Thru 2 Activate (N.O./N.C.)]
Note:
• If stall prevention during deceleration function causes large speed or current ripples and L2-29 = 1, H1-xx = 7A or 7B, or L3-04 = 2,
gradually decrease this parameter in 0.05-unit increments. If the drive detects ov [Overvoltage] or oC [Overcurrent], decrease L3-21. If
you decrease the gain too much, it can cause a delay in control in the DC bus voltage or the deceleration time could be longer than the
best deceleration time.
• If sudden increases in the regenerative load cause ov faults and L3-11 = 1, gradually increase this parameter in 0.1-unit increments. If
there are large speed ripples, gradually decrease this parameter in 0.05-unit increments.
■ L3-22: PM Stall Prevention Decel Time
No.
(Hex.)
Name Description
Default
(Range)
L3-22
(04F9)
PM Stall Prevention Decel
Time
Sets the momentary deceleration time that the drive will use when it tries to accelerate a PM
motor and detected motor stalls. This function is applicable when L3-01 = 1 [Stall Prevention
during Accel = Enabled].
0.0 s
(0.0 - 6000.0 s)
Set this parameter to 0.0 s to disable this function. The drive will decelerates in the deceleration time applicable at
the time when a motor stall occurs.
■ L3-23: Stall P Reduction at Constant HP
No.
(Hex.)
Name Description
Default
(Range)
L3-23
(04FD)
Stall P Reduction at
Constant HP
Sets the function to automatically decrease the Stall Prevention Level during Run for Constant
Horse Power (CHP) part of the speed range.
0
(0, 1)
0 : Use L3-06 for Entire Speed Range
The drive uses the level set in L3-06 [Stall Prevent Level during Run] through the full speed range.
1 : Automatic Reduction @ CHP Region
The drive decreases the Stall Prevention level during run in the constant power range. The lower limit is 40% of
the L3-06 value.
■ L3-24: Motor Accel Time @ Rated Torque
No.
(Hex.)
Name Description
Default
(Range)
L3-24
(046E)
Expert
Motor Accel Time @ Rated
Torque
Sets the motor acceleration time to reach the maximum frequency at the motor rated torque for
stopped single-drive motors.
Determined by o2-04, C6-
01, E2-11, and E5-01
(0.001 - 10.000 s)