Which products are affected? 9300 vector 22…90 kW SW V7.1
Applications
Applications with heavy starting, e. g. extruder
Function description
The motor current is composed of the excitation component and the effective component. The motor magnetising is determined by the excitation current (magnetising current). In order to establish a torque the motor requires active current.
In the vector control mode a magnetising current is injected into the motor after controller enable. The drive controller determines the Lenze setting of the current amount by means of the motor data.
If a too small motor magnetising current is injected after controller enable the following drive behaviour occurs:
The required torque is not generated during standstill. When accelerating a large load out of standstill a current overshoot occurs. OC1 may trip. The machine does not run smoothly since the motor is underexcited. Note:
If problems occur concerning the current injection into the motor we recommend to operate the drive controller with a sine-modulated switching frequency (C0018 = 0, 1, 4, 5, 6). It is not recommended to use the flat-top modulation (C0018 = 2 or 3).
Attention:
If the motor is operated in stand still mode for a longer period of time there is the risk (especially for small motors) that the motor is destroyed by overtemperature.
We recommend to connect a thermal contact (normally closed), PTC or KTY and to activate the motor temperature monitoring of the drive controller. Self-ventilated motors are to be operated with an external fan if necessary. Basic setting:
A detailed function description can be found in the attachment (pdf file 44 kB).
