Lenze EVF9333−xV - Manual (Page 327)

Configuration
Function blocks
Internal motor control with vector control (MCTRL2)
8
8.2
8.2.7
l
8.2−65 EDSVF9333V EN 6.2−04/2012
The flying restart circuit is especially suitable for applications with fan and
drives with great mass inertia.
The flying restart circuit serves to enable the controller although the motor
still rotates. The flying restart circuit automatically detects the current
motor speed using this speed to start the motor control. This prevents the
motor from braking to zero speed with subsequent acceleration.
Use C0140 to determine the search direction during the flying restart
process.
ƒ If the direction of rotation of the coasting machine is known, you can
search in the direction of rotation or in the direction of the applied
setpoint.
ƒ If the direction of rotation of the coasting machine is not known, you
can search in both directions of rotation or in both directions of the
applied setpoint.
In case of applications with fan, for example, search is possible in both
directions if the direction of rotation of the free−running fan impeller is
not known due to the air flow.
)
Note!
ƒ The flying restart circuit is optimised for a power−adapted
motor. Thus, the rated motor current should not exceed the
rated controller current.
ƒ Although the flying restart circuit is activated (C0142 = 2 or
C0142 = 3), the flying restart process does not start if the pulse
inhibit is deactivated again after an OU message.
In order to start the flying restart process, connect e.g. the
input DCTRL−CINHx with the output signal MONIT−OU. An OU
message causes an internal controller inhibit. When the
controller inhibit is deactivated, the flying restart process is
started.
Special features of vector control
ƒ With a known motor speed there is no need of the flying restart circuit
if a suitable setpoint becomes effective instantaneously after controller
enable (e.g. assign setpoint to NSET−CINH−VAL).
ƒ By selecting a suitable setpoint the flying restart processes can be
reduced to approx. 200 ms.
ƒ For operation with feedback there is no need to activate the flying
restart circuit as the signal as the signal MCTRL−NACT acts as the
setpoint at NSET−CINH−VAL
.
Automatic speed detection
after controller enable − flying
restart circuit