YASKAWA Varispeed f7 Programming Manual Download

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Programming 181

Stall Prevention

L3-01

Stall Prevention Selection
During Accel

StallP Accel Sel

Selects the stall prevention method used to prevent excessive
current during acceleration.
0: Disabled - Motor accelerates at active acceleration rate. The

motor may stall if load is too heavy or accel time is too short.

1: General Purpose - When output current exceeds L3-02 level,

acceleration stops. Acceleration will continue when the output
current level falls below the L3-02 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.

0 to 2

L3-02

Stall Prevention Level
During Acceleration

StallP Accel Lvl

This function is enabled when L3-01 is “1” or “2”.
Drive rated current is 100%. Decrease the set value if stalling or
excessive current occurs with factory setting.

0 to 200

Varies

Duty

Rating*

L3-03

Stall Prevention Limit During
Acceleration

StallP CHP Lvl

Sets the lower limit for stall prevention during acceleration, as a
percentage of the Drive’s rated current, when operation is in the
frequency range above E1-06 (constant power region).

0 to 100

50%

L3-04

Stall Prevention Selection
During Deceleration

StallP Decel Sel

When using a braking resistor, use setting “0”. Setting “3” is used
in specific applications.
0: Disabled - The Drive decelerates at the active deceleration rate.

If the load is too large or the deceleration time is too short, an
OV fault may occur.

1: General Purpose - The Drive decelerates at the active

deceleration rate, but if the main circuit DC bus voltage reaches

the stall prevention level (380/760Vdc), deceleration will stop.
Deceleration will continue once the DC bus level drops below
the stall prevention level.

2: Intelligent - The active deceleration rate is ignored and the Drive

decelerates as fast as possible w/o hitting OV fault level.
Range: C1-02 / 10.

3: Stall Prevention w/ Braking Resistor - Stall prevention during

deceleration is enabled in coordination with dynamic braking.

0 to 3

L3-05

Stall Prevention Selection
During Running

StallP Run Sel

Selects the stall prevention method to use to prevent Drive faults
during run.
0: Disabled - Drive runs a set frequency. A heavy load may cause

the Drive to trip on an OC or OL fault.

1: Decel Time 1 - In order to avoid stalling during heavy loading,

the Drive will decelerate at Decel time 1 (C1-02) if the output
current exceeds the level set by L3-06. Once the current level
drops below the L3-06 level, the Drive will accelerate back to its
frequency reference at the active acceleration rate.

2: Decel Time 2 - Same as setting 1 except the Drive decelerates at

Decel Time 2 (C1-04).

When output frequency is 6Hz or less, stall prevention during

running is disabled regardless of L3-05 setting.

0 to 2

L3-06

Stall Prevention Level
During Running

StallP Run Level

This parameter is enabled when L3-05 is set to “1” or “2”.
Drive rated current is set as 100%.
Decrease the set value if stalling or excessive current occurs with
factory setting.

30 to

200

Varies

Duty

Rating*

L3-11

OV Suppression Function
Selection

OV Inhibit Sel

Enables or disables OV suppression function, which allows the
Drive to change the output frequency as the load changes, to
prevent OV fault.
0: Disabled
1: Enabled

0 to 1

L3-12

OV Suppression Function
Voltage Level

OV Inhbt VoltLvl

Sets the DC bus voltage level at which the OV suppression
function is active.

350 to

390

(240V)

700 to

780

(480V)

380V