Mitsubishi Electric FR-A700 Instruction Manual page 439

Parameter
Set stop-on-contact control
● Make sure that the inverter is in external operation mode. (Refer to section 6.22.1.)
● Select either real sensorless vector control or advanced magnetic flux vector control.
● Set"1 or 3" 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.
NOTES
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 diferent 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 change to a mechanical brake to hold the load.
Under the following operating conditions, the stop-on-contact functionis made invalid:
PU operation (Pr. 79)
Jog operation (JOG signal)
PU+external operation (Pr. 79)
PID control function operation (Pr.128)
Remote setting function operation (Pr. 59)
Start time tuning
Orientation control function operation (FR-A7AP option)
When performing stop-on-contact control during encoder feedback control, encoder feed-
back control is made invalid due to a mode shift to the stop-on-contact control mode.
Function switching of stop-on-contact control selection
Main Functions
Output frequency
Stall prevention opera-
tion level
Torque limit level
Excitation current low
speed scaling factor
Carrier frequency
Fast-response current
limit
Tab. 6-69: Function switching of stop-on-contact control selection
When RL and RT are on, Pr. 49 "Second stall prevention operation frequency" is invalid.
FR-A700 EC
Normal Operation
(either RL or RT is off or both are off)
Real sensorless Advanced magnetic
vector control flux vector control
Multi-speed
0 to 5V, 0 to 10V, 4 to 20mA etc.
— Pr. 22
—
—
Pr. 72
—
Motor brake and stop operation
With stop-on-contact Control
(both RL and RT are on)
Real sensorless
vector control
—
Pr. 22
—
Pr. 276 setting when output frequency is 3Hz
or less (Pr. 72 when Pr. 276 = "9999")
Valid —
Advanced magnetic
flux vector control
Pr. 6
The smaller value set
in either Pr. 22 or
Pr. 48
—
The current is com-
pensated for by
Pr. 275 (0 to 1000%)
settings before RL
and RT are switched
on.
Invalid
6 - 259