Operating Instructions ACU
Contact-controlled:
If parameter Braking Time 632 is set to the value 0.0 s, the direct current brake is controlled by
the Start clockwise and Start anticlockwise signals. The time monitoring and limitation by Braking
Time 632 are deactivated. The braking current will be impressed until the controller enable control
signal (S1IND/STOA and S7IND/STOB) becomes logical 0 (low).
To avoid current surges, which can possibly lead to an error switch-off of the frequency inverter, a
direct current may only be impressed into the motor after the motor has been demagnetized. As the
demagnetization time depends on the motor used, it can be set with the parameter Demagnetizing
Time 633.
The selected demagnetizing time should be approximately three times the Act. Rotor Time Constant
227.
The selected stopping behavior is supplemented by a current controller to control the direct current
brake. The compensated proportional regulator controls the current impression of the parameterized
Braking Current 631. The proportional and integrating part of the current controller can be set via
parameters Amplification 634 and Integral Time 635. The control functions can be deactivated by
setting the parameters to 0.
13.4 Auto start
Comply with VDE provision 0100 part 227 and provision 0113, in particular Sections
5.4, protection against automatic after main line voltage failure and voltage recovery,
and Section 5.5 "Undervoltage protection".
Appropriate measures must be taken to exclude any risk for staff, machines and
production goods.
In addition to that, all specific regulations relevant to the application as well all
national directives are to be complied with.
When the Autostart function is activated, the operator, in accordance with DIN EN
61800-5-1, shall provide a clear warning/sign in the plant, indicating automatic
restart.
The auto start function is suitable for applications which permit a start at mains voltage by their
function. By activation of the auto-start function via parameter Operation Mode 651, the frequency
inverter accelerates the drive after application of the mains voltage. Control signals STOA and STOB
for release and the start command are required as per the regulations. When the motor is switched
on, it is accelerated according to the parameterization and the reference value signal.