Mitsubishi Electric FR-F820-00077 Instruction Manual page 353

Parameters
Pr.
154
H631
V/F V/F V/F
Magnetic flux Magnetic flux Magnetic flux V/F V/F V/F
157
M430
858
T040
868
T010
874
H730
Magnetic flux Magnetic flux Magnetic flux V/F V/F V/F PM PM PM
The upper limit of stall prevention operation is limited internally to the following:
120% (SLD rating), 150% (LD rating)
Setting the stall prevention operation level (Pr. 22)
Fig. 5-64:
● For Pr. 22 "Stall prevention operation level", set the ratio of the output current to the inverter's
rated current at which the stall prevention operation will be activated. Normally, use this param-
eter in the initial setting.
● Stall prevention operation stops acceleration (makes deceleration) during acceleration, makes
deceleration during constant speed, and stops deceleration during deceleration.
● When the stall prevention operation is performed, the Overload warning (OL) signal is output.
NOTES A continuous overloaded condition may activate a protective function such as motor overload trip
(electronic thermal O/L relay function) (E.THM).
When Pr. 156 has been set to activate the fast response current limit (initial value), the Pr. 22 set-
ting should not be higher than 140%. Such setting will prevent torque generation.
Under PM motor control, the stall prevention operation level is reduced inversely proportional to
the output frequency in the constant output range of the rated motor frequency or higher.
FR-F800
Initial value
Name
FM
Voltage reduction
selection during stall
prevention operation
OL signal output timer
Terminal 4 function
assignment
Terminal 1 function
assignment
OLT level setting 120%
Pr. 22
OL
Stall prevention operation example
Setting range Description
CA
Output voltage
0
reduction enabled.
Output voltage
1
reduction disabled.
Output voltage
10
1 reduction enabled.
Output voltage
11
reduction disabled.
Set the OL signal output start time when stall
0 to 25 s
prevention is activated.
0s
9999 No OL signal output.
When set "4", the stall prevention level can be
0 0, 4, 9999
changed with the signal to the terminal 4.
When set "4", the stall prevention level can be
0 0, 4, 9999
changed with the signal to the terminal 1.
A trip can be set for when the stall prevention is
110% 0 to 400% activated and the motor stalls. Set the output at
which to activate the trip.
Output current
Output frequency
Constant speed
(H) Protective function parameter
Enable/disable the
output voltage
reduction during stall
prevention operation.
Use this setting when
the overvoltage
protective function
(E.OV[ ]) activates
during stall prevention
operation in an
application with large
load inertia.
Time
I001120E
5 - 181