Stall Prevention (Pr. 22, Pr. 23, Pr. 66, Pr. 148, Pr. 149, Pr. 154) - Mitsubishi FR-A500 Series Instruction Manual

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"
Pr. 66 "stall prevention operation level
reduction starting frequency"
Pr. 148 "stall prevention operation level
at 0V input"
Pr. 149 "stall prevention operation level
at 10V input"
Pr. 154 "voltage reduction selection during stall
prevention operation"
" Set the output current level at which the output frequency will be adjusted to prevent the inverter from
stopping due to overcurrent etc.
" 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 〈50Hz〉 in Pr. 66 and 100% in Pr. 23.
" 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.
" 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.
" The stall prevention operation level can be varied by entering the analog signal into terminal 1.
Parameter Factory
Number Setting
22 150%
23 9999
60Hz 〈50Hz〉
66
148 150%
149 200%
154 1
Pr.22
(170%)
(130%)
0%
0V
Input voltage (V)
(across frequency setting terminals 1-5)
Setting Range
0 to 200%, 9999
0 to 200%, 9999
0 to 400Hz
0 to 200%
0 to 200%
0, 1
Pr. 23 = 9999
Pr.23
Reduction ratio
compensation factor (%)
400Hz Output frequency (Hz)
Pr.66
Pr.149
Pr.148
10(5)V
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"
Remarks
9999: Analog variable
9999: Constant according to Pr. 22
(Bias)
(Gain)
0: Output voltage reduced
1: Output voltage not reduced
Setting example (Pr.22=150%, Pr.23=100%, Pr.66=60Hz)
150
90
60
45
30
22.5
0 60 100
77
PARAMETERS
200 300 400
Output frequency (Hz)
4