Mitsubishi Electric FR-A700 Series, Техническое руководство

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397
PARAMETER
2
P
ARAM
ETE
R
Confirm that the External operation mode is selected. In
, select Real sensorless vector control or Advanced
magnetic vector control. This function is not activated
during V/F control and vector control.
In
, select Advanced magnetic flux vector control or
General-purpose magnetic vector control. This function is
not activated during V/F control.
In ,
set [ Pr. 270 Stop-on contact/load torque high-speed
frequency control selection =1 or 3]. In , set [ Pr. 270 Stop-
on contact control selection =1].
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.
Under Advanced magnetic flux vector control and General-
purpose magnetic flux control, increasing the [
Pr. 275 ]
setting enhances excitation at the low speed and increases
torque. Normally set this parameter within the range about
130 to 180%. If the setting is too large, overcurrent fault
(E.OC 1 to 3) 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 hold the load by a mechanical brake.
Under the following operating conditions, the stop-on-
contact function is 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 (only in )
• Orientation control function operation (only in )
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.
A700
E700
A700
E700
A700
A700
(a) (b) (c)
Time
[ Pr. 4 ]
RH
RM
RL
RT
[ Pr. 5 ]
[ Pr. 6 ]
Output frequency
0
Normal mode Stop-on contact
control mode
(a):Acceleration time ([ Pr. 7 ])
(b):Deceleration time ([ Pr. 8 ])
(c):Second deceleration time ([ Pr. 44 ])
*
ON OFF
ON OFF
ON OFF
ON
Goes into stop-on-contact control mode when
both RL and RT switch ON.
RL and RT may be switched ON in any order
with any time difference
*
A700
Main Functions
Normal Operation
(either RL or RT is OFF or both are OFF)
With Stop-on-contact Control
(both RL and RT are ON)
Real sensorless
vector control
Advanced
magnetic flux vector
control
Real sensorless
vector control
Advanced
magnetic flux vector
control
Output frequency
Multi-speed
0 to 5V, 0 to 10V
4 to 20mA etc.
[ Pr. 6 ] setting
Stall prevention operation
level
— [ Pr. 22 ] setting —
The setting value of [ Pr.
48 ] or [ Pr. 22 ],
whichever is smaller
*
Torque limit level [ Pr. 22 ] setting — [ Pr. 22 ] setting —
Excitation current low
speed scaling factor
— —
[ Pr. 275 ] (0 to 1000%)
is compensated from
normal operation
Carrier frequency [ Pr. 72 ] setting
Output frequency is 3Hz or less
[ Pr. 276 ] setting ([ Pr. 72 ] when [ Pr. 276 = 9999 ])
Fast-response current
limit
— Valid — Invalid
* When RL and RT are ON, [ Pr. 49 Second stall prevention operation frequency ] is invalid.