Yaskawa V7 Drives - Manual (Page 87)

5-35
A. n092 : Stall Prevention During Deceleration Factory setting: 0
Setting Function
0 Stall prevention during deceleration enabled
1 Stall prevention during deceleration disabled
Stall prevention during deceleration automatically
adjusts the deceleration rate while monitoring the
DC bus voltage to prevent overvoltage during
deceleration.
When the motor load is large or decel time is
short, actual decel time may be longer than the
set value because of stall prevention
.
B. n093 : Stall Prevention Level During
Factory setting: See Table A3-1
Acceleration
Range: 30 - 200 %
This parameter determines the actual Drive output current level during an acceleration condition. Set in
percent of Drive rated output current.
A setting of " 200 " disables stall
prevention during acceleration. During
acceleration, if the output current
exceeds the value in
n093 , acceleration
stops and frequency is maintained.
When the output current goes below the
value set in
n093 , acceleration resumes.
In the constant horsepower region
[actual output frequency
≥ max. voltage
frequency ( n013 )], the stall prevention
level during acceleration is changed by
the following formula:
Stall prevention level during
= Stall prevention level during accel x
Max. voltage frequency
accel (constant horsepower) Actual output frequency
5.23 STALL PREVENTION
TIME
FREQUENCY
SET
DECEL
TIME
Controls the
deceleration
time needed to
prevent over-
voltage fault.
C. n094 : Stall Prevention Level At Set Speed Factory setting: 160%
Range: 30 - 200 %
This parameter determines the actual
Drive output current level while operating
at set speed (frequency). Set in percent
of Drive rated output current (see
Appendix 2).
A setting of " 200 " disables stall
prevention at set speed. During running
at set speed, if the output current exceeds
the value set in
n094 , the drive will begin
to decelerate. When the output current
goes below the value set in
n094,
acceleration begins, up to the set
frequency.
t
t
MOTOR
CURRENT
OUTPUT
FREQ.
Constant
n074
setting
Parameter
n094
Setting
t
t
MOTOR
CURRENT
OUTPUT
FREQ.
Constant
n073
setting
Parameter
n093
Setting