Mitsubishi Electronics FR-A500 ユーザーズマニュアル
84
4.2.12 Stall prevention (Pr. 22, Pr. 23, Pr. 66, Pr. 148, Pr. 149, Pr. 154)
Pr. 22 "stall prevention operation level"
Pr. 23 "stall prevention operation level
compensation factor at double speed"
compensation factor at double speed"
Pr. 66 "stall prevention operation level
reduction starting frequency"
reduction starting frequency"
Pr. 148 "stall prevention operation level
at 0V input"
at 0V input"
Pr. 149 "stall prevention operation level
at 10V input"
at 10V input"
Pr. 154 "voltage reduction selection during stall
prevention operation"
prevention operation"
z
Set the output current level at which the output frequency will be adjusted to prevent the inverter from
stopping due to overcurrent etc.
z
For high-speed operation at or over the more base frequency, acceleration may not be made because the
motor current does not increase. To improve the operation characteristics of the motor in such a case, the
stall prevention level in the high-frequency range can be reduced. This is effective for operation of a
centrifugal separator up to the high-speed range. Normally, set 60Hz in Pr. 66 and 100% in Pr. 23.
stall prevention level in the high-frequency range can be reduced. This is effective for operation of a
centrifugal separator up to the high-speed range. Normally, set 60Hz in Pr. 66 and 100% in Pr. 23.
z
For operation in the high-frequency range, the current in the locked motor state is smaller than the rated
output current of the inverter and the inverter does not result in an alarm (protective function is not
activated) if the motor is at a stop. To improve this and activate the alarm, the stall prevention level can be
reduced.
activated) if the motor is at a stop. To improve this and activate the alarm, the stall prevention level can be
reduced.
z
In order to provide torque during stall prevention, Pr. 154 is factory-set not to reduce the output voltage.
The setting of reducing the output voltage further decreases the probability of overcurrent trip occurrence.
z
The stall prevention operation level can be varied by entering the analog signal into terminal 1.
Parameter
Number
Factory
Setting
Setting Range
Remarks
22
150%
0 to 200%, 9999
9999: Analog variable
23
9999
0 to 200%, 9999
9999: Constant according to Pr. 22
66
60Hz
0 to 400Hz
148
150%
0 to 200%
(Bias)
149
200%
0 to 200%
(Gain)
154
1
0, 1
0: Output voltage reduced
1: Output voltage not reduced
1: Output voltage not reduced
Pr.22
Pr.23
Pr.66
400Hz Output frequency (Hz)
S
tal
l p
rev
e
n
ti
on
oper
at
io
n l
e
vel
(%
)
Pr. 23
= 9999
Reduction ratio
compensation factor (%)
150
90
60
45
30
30
22.5
60
0
100
200
300
400
Output frequency (Hz)
Setting example (Pr.22=150%, Pr.23=100%, Pr.66=60Hz)
S
tal
l pr
even
ti
on o
per
ati
o
n
l
e
vel
(%
)
(170%)
(130%)
0%
0V
Pr.148
Pr.149
10(5)V
Input voltage (V)
(across frequency setting terminals 1-5)
(across frequency setting terminals 1-5)
S
ta
ll p
rev
enti
o
n
op
e
ra
ti
o
n l
e
ve
l
(%
)
Related parameters
Pr. 48 "second stall prevention
operation current"
Pr. 49 "second stall prevention operation
frequency"
Pr. 73 "0-5V/0-10V selection"
Pr. 114 "third stall prevention operation
current"
Pr. 115 "third stall prevention operation
frequency"
Pr. 156 "stall prevention operation
selection"
operation current"
Pr. 49 "second stall prevention operation
frequency"
Pr. 73 "0-5V/0-10V selection"
Pr. 114 "third stall prevention operation
current"
Pr. 115 "third stall prevention operation
frequency"
Pr. 156 "stall prevention operation
selection"