Mitsubishi Electric FR-F820-00077 Instruction Manual page 357

Parameters
Setting multiple stall prevention operation levels (Pr. 48, Pr. 49)
● By setting Pr. 49 "Second stall prevention operation frequency" = "9999" and turning ON the RT
signal, Pr. 48 "Second stall prevention operation level" will be enabled.
● For Pr. 48, set the stall prevention operation level that is effective in the output frequency range
between 0 Hz and Pr. 49. However, the operation level is Pr. 22 during acceleration.
● Stop-on-contact operation can be used by decreasing the Pr. 48 setting and loosening the
reduction torque (torque when stopped).
Tab. 5-81:
For the stall prevention operation level, the smaller of Pr. 22 and Pr. 48 has precedence.
When Pr. 858 = "4 (analog input to terminal 4 for stall prevention operation level)" or Pr. 868 = "4
(analog input to terminal 1 for stall prevention operation level)", turning ON the RT signal will not
enable the second stall prevention function. (Input to the terminal 4 or terminal 1 is valid.)
Pr. 48
Fig. 5-68:
NOTES When Pr. 49 ≠ "9999" (level change according to frequency) and Pr. 48 = "0%", the stall prevention
function will be disabled at or lower than the frequency set in Pr. 49.
The RT signal is assigned to the terminal RT in the initial status. Set "3" in any of Pr. 178 to Pr. 189
(input terminal function selection) to assign the RT signal to another terminal.
Changing the terminal assignment using Pr. 178 to Pr. 189 (input terminal function selection) may
affect the other functions. Set parameters after confirming the function of each terminal.
The RT signal acts as the second function selection signal and makes the other second functions
valid. (Refer to page 5-291.)
FR-F800
Pr. 49 setting Operation
0 (initial value) The second stall prevention function disabled.
0.01 Hz to 590 Hz
The second stall prevention function operates according to the frequency.
The second stall prevention function operates according to the RT signal.
RT signal ON: stall level Pr. 48
9999
RT signal OFF: stall level Pr. 22
Settings of parameter 49
During acceleration
Set frequency
During deceleration/constant speed
Pr. 49
Running frequency
Stall prevention operation level setting example
Output
frequency (Hz)
Output
frequency
Pr. 49
Time
Stall
prevention
level
Pr. 22 used
Pr. 48 used
Set frequency is
Pr. 49 or less
(H) Protective function parameter
V/F V/F V/F Magnetic flux Magnetic flux Magnetic flux
Output
frequency (Hz)
Output
frequency
Set frequency
Pr. 49
Stall
prevention
Pr. 22 used
level
Pr. 48 used
exceeds Pr. 49
Set frequency
Time
I002599E
5 - 185