Siemens SIRIUS 3RT Series System Manual page 139

1
2
Figure 2-14
Changing the direction of rotation from clockwise to counterclockwise
NOTICE
In order to set the motor to counterclockwise rotation, it is not simply a case of swapping
over two phases at any location. This would result in the same conditions as those
described for clockwise rotation.
The wiring must be performed as follows in order to keep the switchover current peak which
occurs on switching from star (wye) to delta as low as possible here too:
Figure 2-15
Table 2- 15
Star contactor
I motor x 0.33
e
Note
If two phases are swapped over in the network in order to change the direction of rotation,
the circuit is automatically changed/reversed from the most favorable to the least favorable.
SIRIUS Innovations
System Manual, 01/2011, A8E56203870002-03
Rotating field
Rotor's overtravel during the current-free phase
Phasor diagram for motor phase connections made according to the previous diagram
results in a high switchover current peak
Correct connection of motor phases for counterclockwise motor rotation
Device sizing during normal starting
SIRIUS 3RT2 contactors/contactor assemblies
Line and delta contactor
I motor x 0.58
e
2.4 Configuration
Overload relay
I motor x 0.58
e
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