Mitsubishi Electric FR-A700 Instruction Manual page 491

Parameter
Low speed detection (LS signal, Pr. 865)
The low speed detection signal (LS) is output when the output frequency reduces below the Pr.
865 "Low speed detection setting".
When speed control is performed by real sensorless vector control or vector control, an alarm
(E.OLT) is displayed and the inverter output is stopped if frequency drops to the Pr. 865 setting
by torque limit operation and the output torque exceeds Pr. 874 OLT level setting and remains
for more than 3s.
For the LS signal, set "34 (source logic) or 134 (sink logic)" in Pr. 190 to Pr. 196 (output terminal
function selection) and assign functions to the output terminal.
NOTES
The FU signal is assigned to the terminal FU and the SU signal is assigned to the terminal
SU in the initial setting.
All signals are OFF during DC injection brake, pre-excitation (zero speed control, servo
lock), or start time tuning.
The output frequency to be compared with the set frequency at the SU signal and LS signal
differs according to the control method.
Control Method
V/f control
Advanced magnetic flux vector
control
Real sensorless vector control
Encoder feedback control,
vector control
When terminal assignment is changed using Pr. 190 to Pr. 196 (output terminal function
selection), the other functions may be affected. Please make setting after confirming the
function of each terminal
FR-A700 EC
Function assignment of external terminals
Compared Output Frequency
Output frequency
Output frequency before slip compensation
Frequency (actual motor speed) estimated value
Value of actual motor rotation represented in terms of fre-
quency setting
6 - 311