Mitsubishi Electric FR-F740 EC Instruction Manual page 198

Motor torque
Set multiple stall prevention operation levels (Pr. 48, Pr. 49)
Setting "9999" in Pr. 49 "Second stall prevention operation frequency" and turning the RT signal
on make Pr. 48 "Second stall prevention operation current" valid.
Pr. 48
In Pr. 48, you can set the stall prevention operation level at the output frequency from 0Hz to that
set in Pr. 49. During acceleration, however, the operation level is as set in Pr. 22.
This function can also be used for stop-on-contact or similar operation by decreasing the Pr. 48
setting to weaken the deceleration torque (stopping torque).
Pr. 49 Setting
0 (Initial setting)
0.01Hz–400Hz
Tab. 6-3:
The smaller setting of the stall prevention operation levels set in Pr. 22 and Pr. 48 has a
higher priority.
When Pr. 22 = "9999" (Stall prevention operation level analog input), the stall prevention
operation level also switches from the analog input (terminal 1 input) to the stall prevention
operation level of Pr. 48 when the RT signal turns on. (The second stall prevention operation
level cannot be input in an analog form.)
6 - 48
[%]
During deceleration/constant speed
Pr. 49
Running frequency
Operation
The second stall prevention operation is not performed.
If the output frequency is equal to or less than the frequency set in Pr. 49, the second
stall prevention function activates. (During constant speed or deceleration)
The second stall prevention function is performed according to the RT signal.
9999 RT signal ON ... Stall level Pr. 48
RT signal OFF ... Stall level Pr. 22
Settings of parameter 49
Fig. 6-6:
Second stall prevention operation current
setting example
[%]
Parameter
I000022C