YASKAWA GA700 Technical Manual page 846

11.9 L: Protection Function
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L3-03: Stall Prevent Limit during Accel
No.
Name
(Hex.)
L3-03 Stall Prevent Limit
during Accel
(0491)
The stall prevention level set in L3-02 [Stall Prevent Level during Accel] is automatically reduced when the motor
is running within the constant output range. Parameter L3-03 is the limit value used to prevent the stall prevention
level during constant output ranges to fall below the minimum required level.
Note:
The function to automatically reduce the stall prevention level does not operate when L3-01 = 3 [Stall Prevent Select during Accel =
ILim Mode].
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L3-04: Decel Stall Prevention Selection
No.
Name
(Hex.)
L3-04 Stall Prevention
during Decel
(0492)
Note:
Use setting 0 or 3 in combination with a Dynamic Braking Resistor or other dynamic braking options. If this parameter is set to a value
other than 0 or 3, the Decel Stall Prevention function has priority, and the dynamic braking option will not function.
Stall Prevention during deceleration controls the deceleration based on the DC bus voltage and prevents an ov
[DC Bus Overvoltage] caused by high inertia or rapid deceleration.
0 : Disabled
The drive decelerates according to the set deceleration time. With a rapid deceleration, an ov may occur.
Note:
Connect the dynamic braking option to the drive if an ov occurs. Set L3-04 = 3 if an ov occurs while operating with the dynamic braking
option with A1-02 = 0 or 2 [Control Method Selection = V/f Control, Open Loop Vector Control] and L3-04 = 0.
1 : General Purpose
The drive decelerates according to the set deceleration time. The drive pauses deceleration when the DC bus
voltage exceeds the Stall Prevention level and then continues deceleration when the DC bus voltage drops below
that level. The drive resumes deceleration at the set deceleration time once the DC bus voltage drops below the
stall prevention level. Using Stall Prevention repeatedly helps prevent detections of an ov even when the
deceleration time is set shorter than the drive is normally capable of handling.
Note:
The Decel Stall Prevention function will extend the deceleration time to reach stop, so that the deceleration time will be longer than
what has been set. This function is not appropriate for applications such as conveyors, where the precision of the stop position is
extremely important. Consider using a dynamic braking option instead in such applications.
The DC bus voltage level for Stall Prevention depends on the input voltage setting of E1-01 [Input AC Supply
Voltage].
846
V/f CL-V/f OLV CLV AOLV
Sets the lower limit for the stall prevention level during acceleration used
for constant output ranges, as a percentage of the drive rated output current.
Figure 11.130 Stall Prevent Level during Accel/Limit
V/f CL-V/f OLV CLV AOLV
Selects the type of Stall Prevention during deceleration.
YASKAWA ELECTRIC SIEP C710617 01B YASKAWA AC Drive GA700 Technical Manual
Description
OLV/PM AOLV/PM CLV/PM EZOLV OLV/PM
Description
OLV/PM AOLV/PM CLV/PM EZOLV OLV/PM
Default
(Range)
50%
(0 - 100%)
Default Setting
(Range)
1
(0 to Determined by
A1-05)