FR-A701 INSTRUCTION MANUAL (Applied) - Automation Systems ...

Function assignment of external terminal and control(3) Low speed detection (LS signal, Pr. 865)Output frequency(Hz)LSPr.865ONOFFONTime⋅ The low speed detection signal (LS) is output when theoutput frequency reduces below the Pr. 865 Low speeddetection setting.⋅ When speed control is performed by real sensorlessvector control or vector control, a fault (E.OLT) isdisplayed and the inverter trips if frequency drops to thePr. 865 setting by torque limit operation and the outputtorque exceeds Pr. 874 OLT level setting and remains formore than 3s.⋅ For the LS signal, set "34 (positive logic) or 134 (negativelogic)" in Pr. 190 to Pr. 196 (output terminal functionselection) and assign functions to the output terminal.REMARKS⋅ 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 controlmethod.Control MethodV/F controlAdvanced magneticflux vector controlReal sensorlessvector controlEncoder feedbackcontrol, vector controlCompared Output FrequencyOutput frequencyOutput frequency before slip compensationFrequency (actual motor speed) estimated valueValue of actual motor rotation represented in termsof frequency setting⋅CAUTIONChanging the terminal assignment using Pr. 190 to Pr. 196 (output terminal function selection) may affect the other functions.Please make setting after confirming the function of each terminal.♦ Parameters referred to ♦Pr. 190 to Pr. 196 (output terminal function selection) Refer to page 214Pr. 874 OLT level setting Refer to page 83222