
Pump type WK/ SMK
Version: 27220 - E
Schmalenberger GmbH + Co. KG
D-72072 Tübingen / Germany
17
4.2.1.
Connection Diagrams for Three-Phase Motors
Fig. 3 Delta connection ∆
(low voltage)
Fig. 4 Star connection Y
(high voltage)
4.2.2.
Time Relay Setting
For three-phase motors with star-delta connection, you must ensure that the switching points between
star and delta follow one after the other in as little time as possible. Longer switching times will result in
damage to the motor. Time delay setting for star-delta connection: < 3 sec.
4.2.3.
Direction of Rotation Check
The direction of rotation of the motor must agree with the direction of the rotation arrow on the motor
housing of the pump. Check by switching on and off in quick succession. If the direction of rotation is
incorrect, reverse any two phases L1, L2 or L3 of the mains power supply line in the motor terminal box.
4.2.4.
Auxiliary Equipment for Motor
If special control devices are provided, for example in conjunction with use of the centrifugal pump in a
technical system, the manufacturer's instructions for these control devices must always be observed.
For additional information, see the Operator's Manual Pump Control (27122).