Stall Prevention Operation - Mitsubishi Electric FR-E700 Instruction Manual

Adjust the output torque (current) of the motor
6.3.5

Stall prevention operation

(Pr. 22, Pr. 23, Pr. 48, Pr. 66, Pr. 156, Pr. 157, Pr. 277)
This function monitors the output current and automatically changes the output frequency to pre-
vent the inverter from coming to trip due to overcurrent, overvoltage, etc. In addition, simple torque
limit which limits the output torque to the predetermined value can be selected.
It can also limit stall prevention and fast-response current limit operation during acceleration/decel-
eration, driving or regeneration.
● Stall prevention
If the output current exceeds the stall prevention operation level, the output frequency of the
inverter is automatically varied to reduce the output current.
● Fast-response current limit
If the current exceeds the limit value, the output of the inverter is shut off to prevent an
overcurrent.
● Torque limit
The inverter output frequency is controlled so that the output torque (torque current) will not
exceed the stall prevention operation level (motor rated torque is referenced).
Pr. No. Name
22
Stall prevention operation level
Stall prevention operation level
23
compensation factor at double speed
Second stall prevention operation
48
current
Stall prevention operation reduction
66
starting frequency
156
Stall prevention operation selection
157
OL signal output timer
Stall prevention operation current
277
switchover
The above parameters can be set when Pr. 160 "User group read selection" = 0.
This parameter allows its setting to be changed during operation in any operation mode even if
"0" (initial value) is set in Pr. 77 "Parameter write selection".
6 - 44
Initial Value Setting Range Description
0 Stall prevention operation invalid
150%
Set the current value to start the stall
0.1–200%
prevention operation.
The stall operation level can be reduced
0–200% when operating at a high speed above the
9999
rated frequency.
9999 Constant according to Pr. 22.
0 Stall prevention operation invalid
9999 0.1–200% Second stall prevention operation level
9999 Same level as Pr. 22.
Set the frequency at which the stall
50Hz 0–400 Hz
operation level is started to reduce.
Select whether stall prevention operation
0–31/
0 and fast-response current limit operation
100/101
will be performed or not.
Output start time of the OL signal output
0–25 s
when stall prevention is activated.
0s
9999 Without the OL signal output
0 Output current is the limit level
0
Output torque (torque current) is the limit
1
level
Parameter
Parameters referred to
3 Base frequency
178–184 Input terminal function
selection
190–192 Output terminal
function selection
Refer to
Section
6.5.1
6.10.1
6.10.5