Siemens MICROMASTER 420, Operating Instructions Manual

Page: 130 / 190

3 Functions Issue 07/04
MICROMASTER 420 Operating Instructions
130
6SE6400-5AA00-0BP0
After the magnetizing time P0346 has expired, the ramp-function generator is set to
the speed actual value and the motor is operated with the actual reference
frequency.
Setpoint frequency
t
f
f
Ramp up
Magnetizing
time
P0346
Demagnetizing
time
P0347
Flying restart
P1202
P1203
search,max
Fig. 3-54 Flying restart
NOTE
If a higher value is entered for the search velocity P1203 this results in a flatter
search curve and therefore to an extended search time. A lower value has the
opposite effect.
For "Flying restart", a braking torque is generated which can cause drives, with
low moments of inertia, to brake.
For group drives, "Flying restart" should not be activated due to the different
characteristics of the individual motors when coasting down.
WARNING
When "Flying restart" is activated (P1200 > 0), although the drive is at a stand-
still and the setpoint is 0, it is possible that the drive is accelerated as a result of
the search current !
If the operating range of the motors is entered when the drive is in this state,
this can result in death, severe injury or material damage.