Mitsubishi Electric 800 Series Instruction Manual page 258

5.7.12 Stall prevention operation
This function monitors the output current and automatically changes the output frequency to prevent the inverter from tripping
due to overcurrent, overvoltage, etc. It can also limit the stall prevention and fast-response current limit operation during
acceleration/deceleration and power/regenerative driving.
• Stall prevention
If the output current exceeds the stall prevention operation level, the output frequency of the inverter is automatically changed
to reduce the output current.
Also the second stall prevention function can limit the output frequency range in which the stall prevention function is enabled.
• Fast-response current limit
If the current exceeds the limit value, the output of the inverter is shut off to prevent an overcurrent.
Pr. Name
22 Stall prevention operation
H500 level
156 Stall prevention operation
H501 selection
48 Second stall prevention
H600 operation level
V/F V/F V/F
Magnetic flux Magnetic flux Magnetic flux
49 Second stall prevention
H601 operation frequency
V/F V/F V/F
Magnetic flux Magnetic flux Magnetic flux
23 Stall prevention operation
H610 level compensation factor at
double speed
V/F V/F V/F
Magnetic flux Magnetic flux Magnetic flux
66 Stall prevention operation
H611 reduction starting frequency
V/F V/F V/F
Magnetic flux Magnetic flux Magnetic flux
148 Stall prevention level at 0 V
H620 input
V/F V/F V/F
Magnetic flux Magnetic flux Magnetic flux
149 Stall prevention level at 10 V
H621 input
V/F V/F V/F
Magnetic flux Magnetic flux Magnetic flux
154 Voltage reduction selection
H631 during stall prevention
operation
V/F V/F V/F
Magnetic flux Magnetic flux Magnetic flux
157 OL signal output timer
M430
858 Terminal 4 function
T040 assignment
868 Terminal 1 function
T010 assignment
874 OLT level setting
H730
PM PM PM
Initial Setting range
value
110% 0
*1
0.1 to 400%
0 0 to 31, 100 to 101
110% 0
*1
0.1 to 400%
0 Hz 0
0.01 to 590 Hz
9999
9999 0 to 200%
9999
60 Hz 0 to 590 Hz
110% *1
0 to 400%
120%
*1
0 to 400%
1 0
1
10
11
0 s 0 to 25 s
9999
0 0, 4, 9999
0 0, 4, 9999
110% 0 to 400%
Description
Stall prevention operation disabled.
Set the current limit at which the stall prevention operation
will start.
Enable/disable the stall prevention operation and the fast-
response current limit operation.
Second stall prevention operation disabled.
The stall prevention operation level can be changed using
the RT signal.
Second stall prevention operation disabled.
Set the frequency at which the Pr.48 stall prevention
operation will start.
Pr.48 is enabled when RT signal is ON.
The stall operation level when running at high speeds
above the rated frequency can be reduced.
Stall prevention operation disabled at double speed.
Set the frequency at which the stall operation level
reduction will start.
The stall prevention operation level can be changed by the
analog signal input to the terminal 1 (terminal 4).
Output voltage Enable/disable the output voltage
reduction enabled. reduction during stall prevention
operation.
Output voltage
reduction disabled.
Output voltage Use this setting when the
reduction enabled. overvoltage protective function
(E.OV[ ]) activates during stall
Output voltage
prevention operation in an
reduction disabled.
application with large load inertia.
Set the OL signal output start time when stall prevention is
activated.
No OL signal output.
When set "4", the stall prevention level can be changed
with the signal to the terminal 4.
When set "4", the stall prevention level can be changed
with the signal to the terminal 1.
A trip can be set for when the stall prevention is activated
and the motor stalls. Set the output at which to activate the
trip.
5.7 (H) Protective function parameter
3
4
5
5
5
6
7
8
9
10
257
5. PARAMETERS