Manual for Induction Motors and Generators
42 -
Mechanical and Electrical Connections
3BFP 000 050 R0101 REV E
Figure 4-1 Typical auxiliary terminal box
4.3.8.1 Connection of auxiliaries and instruments
Connect the instruments and auxiliary equipment according to the connection diagram.
NOTE: Study the connection diagram delivered with the machine carefully before connecting
any cables. The connection and functioning of accessories must be checked before
commissioning.
NOTE: Label terminals of accessories, which are normally under voltage when the machine is
switched off, correspondingly.
4.3.8.2 Connection of external blower motor
The external blower motor is normally a three phase asynchronous motor. A connection box is
usually located on the frame of the blower motor. The external blower motor rating plate shows
the voltage and frequency to be used. The direction of rotation of the fan is indicated by an
arrow plate on the flange of the main machine.
NOTE: Check visually the direction of rotation of the external blower motor (fan) before
starting the main machine. If the blower motor is running in the wrong direction, the
phase sequence of the blower motor must be changed.
4.3.9 Earth connections
The machine frame, main terminal box, auxiliary terminal box and associated equipment must
be connected to protective earth. The connections to protective earth and power supply have to
be able to protect the machine frame from harmful or dangerous electrical potential (voltage).
NOTE: The earthing must be carried out according to local regulations before the machine is
connected to the supply voltage.
NOTE: The warranty does not cover destroyed bearings due to improper earthing or cabling.
Mark the machine and terminal boxes with earth symbols according to relevant national
standards.