Mitsubishi Electric FR-A720-0.4K Instruction Manual page 226

(1) Set stop-on-contact control
⋅ Make sure that the inverter is in External operation mode. (Refer to page 313 )
⋅ Select either Real sensorless vector control or Advanced magnetic flux vector control.
⋅ Set "1, 3, 11 or 13" in Pr. 270 Stop-on contact/load torque high-speed frequency control selection .
⋅ Set output frequency during stop-on-contact control in Pr. 6 Multi-speed setting (low speed).
The frequency should be as low as possible (about 2Hz). If it is set to more than 30Hz, the operating frequency will
be 30Hz.
⋅ When both the RT and RL signals are switched ON, the inverter enters the stop-on-contact mode, in which operation
is performed at the frequency set in Pr. 6 independently of the preceding speed.
⋅ Setting Pr. 270 = "11 or 13" disables E.OLT (stall prevention stop) during stop-on-contact control (with both RL and RT
signals ON).
⋅ To input the RT signal, set "3" in any of Pr.178 to Pr.184 (Input terminal function selection) to assign the function to the
terminal. To input the RL signal, set "0" in any of Pr.178 to Pr.184 (Input terminal function selection) to assign the function
to the terminal.
CAUTION
⋅ By increasing the Pr. 275 setting, the low-speed (stop-on-contact) torque increases, but overcurrent fault (E.OCT) may occur or
the machine may oscillate in a stop-on-contact state.
⋅ The stop-on-contact function is different from servo-lock function, and if used to stop or hold a load for an extended period, this
function can cause the motor to overheat.
After a stop, immediately reset this function and use a mechanical brake to hold the load.
⋅ Under the following operating conditions, the stop-on-contact function is invalid:
·
PU operation (Pr. 79) JOG operation (JOG signal)
·
Remote setting function operation (Pr. 59)
control function operation
⋅ When performing stop-on-contact control during encoder feedback control, encoder feedback control is invalid due to a mode
shift to the stop-on-contact control mode.
(2) Function switching of stop-on-contact control selection
Useful Functions
Output frequency
Stall prevention operation level
Torque limit level
Excitation current low speed
scaling factor
Carrier frequency
Fast response current limit
* When RL and RT are ON, Pr. 49 Second stall prevention operation frequency is invalid.
·
PU+external operation (Pr. 79)
·
Automatic acceleration/deceleration (Pr. 292)
Normal Operation
(either RL or RT is OFF or both are off)
Advanced
Real sensorless
magnetic flux vector
vector control
control
Multi-speed
0 to 5V, 0 to 10V
4 to 20mA etc.
⎯
Pr. 22 setting
Pr. 22 setting
⎯
Pr. 72 setting
⎯
Motor brake and stop operation
·
PID control function operation (Pr. 128)
·
With Stop-on-Contact Control
(both RL and RT are on)
Real sensorless
vector control
⎯
⎯
Pr. 22 setting
⎯
Pr. 276 setting when output frequency is 3Hz or
less (Pr. 72 when Pr. 276 = "9999")
⎯
Valid
·
Start time tuning Orientation
Advanced
magnetic flux vector
control
Pr. 6 setting
The smaller value set
in either Pr. 22 or Pr. 48.
*
⎯
The current is
compensated for by Pr.
275 (0 to 1000%)
settings from normal
operation.
Invalid
215
4