NORD Drivesystems BU0100 - Manual (Page 9)

NORDAC SK 150E
BU 0100 GB Technical Modifications Reserved 9
3 Electronic Soft Starter SK 150E
3.1 Principle of function
The SK 150E allows a soft start-up and run-down of a
three-phase asynchronous motor by a gradual rise or
reduction of the torque to be defined. A smooth start-up is
thereby achieved, preventing damage to the drive
elements by a suddenly applied torque. A 2-phase control
process realizes the drive properties. The selection or
release of the drive occurs through a 24 VDC control
signal. Depending on the operating mode chosen, the
start-up and braking torque as well as the associated time
can be adjusted with potentiometers. 4 slide switches
define the operating mode. The integrated temperature
can be monitored via a temperature probe or control.
For the activation of a brake, a design with a
rectifier - integrated or separately installed in the terminal
box – is available.
Features:
o
A 24 V voltage supplies the control electronics externally. The control logic is potential-separated
from the system voltage.
o
With the release of the drive via a 24 V control signal, the motor is supplied with voltage through a
phase control process. If an integrated brake rectifier is included, then it is connected to the system
voltage through electronic power switches and the electromechanical brake is thereby released.
o
During the entire operation, the motor can be thermally monitored through temperature probes (PTC
resistor or temperature control) thereby acting like an overload cut-out. There are 2 monitoring
modes that can be selected by a slide switch. During automatic operation (slide switch set to [ON]),
the SK 150E switches the motor off automatically and reports the excess temperature by removing the
OK message (fault signal, signal [OK] changes to low). If the automatic operation has not been
selected (slide switch set to [OFF]), then only the OK message is removed and the drive continues to
run. The inputs must be connected with a jumper if temperature monitoring is not desired.
With automatic operation, the motor does not automatically start even after cooling. To restart, the
control signal [RUN-RIGHT] must first be switched off and then on again. Alternatively, the internal
slide switch can be switched [OFF] and [ON] again. Caution, the drive starts immediately!
o
The basic direction is predetermined by the system input phases. This can be altered by exchanging
2 phases on the motor terminal board. With the correct phase sequence (U1, V1, W1), [RUN]
corresponds to a right motor direction.
o
The current status of the SK 150E is shown through 2 LEDs. These are visible from the outside
through a transparent screw plug.
o
Series SK 150E in the versions SK 150E-1-0 and SK 150E-1-BSG2 fulfils the requirements for
explosion protection (ATEX) in Zone 22 according to the currently valid standards according to EN
50281 (guideline 94/9/EG).
SK 150E