8400 motec | Software Manual
Motor control (MCTRL)
Parameterisable additional functions
100
L
Firmware
≤
02.00 - DMS 2.1 EN - 03/2011
5.9.2
Flying restart function
The flying restart circuit uses a simple model of an asynchronous motor which requires
knowledge of the motor stator resistance RS and the rated motor current.
Tip!
In association with the flying restart function, we recommend to read the
information provided in this documentation on the following topic:
Automatic DC-injection braking (Auto-DCB)
General information
This function serves to activate a mode which is used to "catch" a coasting motor during
operation without speed feedback. This means that the synchronicity between controller
and motor is to be adjusted in such a way that a jerk-free transition to the rotating
machines is achieved in the instant of connection.
The drive controller determines the synchronicity by identifying the synchronous field
frequency.
Duration
The "catching" process is completed after approx. 1 ... 2 seconds. The duration is influenced
by the starting value. If the field frequency is not known, we recommend the preset
starting value of 10 Hz.
Note!
• For a correct functioning of the flying restart circuit, we recommend to
perform a parameter identification first.
• The flying restart function works safely and reliably for drives with great
centrifugal masses.
• Do not use the flying restart function if several motors with different
centrifugal masses are connected to a controller.
• After the controller is enabled, the motor can start for a short time or reverse
when machines with low friction and low mass inertia are used.
• The flying restart function serves to identify max. field frequencies up to
±200 Hz.
• When power-adapted standard asynchronous motors are used (rated motor
power approximately corresponds to the rated inverter power), a motor
parameter identification is not required.
Summary of Contents for 8400 motec Series
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