Siemens induction motors- generators cgii Benutzerhandbuch

 

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Hazardous voltage. 
Will cause death, serious injury, 
electrocution or property damage. 
Disconnect all power before working on 
this equipment. 

 

Before running motor, see Initial Start. 

 

Starting and overload control devices must be matched 
to motor rating.  For safety or convenience they may 
need to be installed some distance from the motor.  
Follow the control manufacturer’s instructions to make 
proper installations and connections.  Observe the 
following: 

 

1.  Connect electrical power supply to conform with 

National Electric Code and any local regulations.  
Line voltage and wire capacity must match motor 
rating stamped on the nameplate. 

2. With the driven equipment disconnected, 

momentarily energize the motor to check rotation. 

3.  If motor is three-phase type, reverse rotation (if 

required) by interchanging any two of the three 
power leads. 

 

Look for rotation plates usually mounted on opposite 
drive end of the motor. 
 

Excessive heat. 
Motor may overheat if motor cooling fans run in the 
wrong direction. 
Run motor in direction shown on motor or change fans. 

 
The internal rotor fan direction must be considered if 
changing direction of rotation. See the following 
Internal Rotor Cooling Fan table to identify which 
motors have directional fans. 
 

 

(2 pole) 

(4 or more poles) 

Rotor Material 

Aluminum Copper Aluminum 

Copper 

500, 580 

Frames 

1 4 3 

3 

680, 800 

Frames 

N/A 4 N/A 

3 

1120 Frame 

N/A 

N/A 

N/A 

2 

1. 

Inspect rotor to determine whether alternative A or B 
below applies; 

A.  If the rotor has integrally cast directional fans, 

either rotor machining instructions and 
conversion parts can be purchased from the 
factory or the rotor core may be removed from 
the shaft, switched end-for-end, and 
remounted on the shaft. 

B.  If the rotor has shaft-mounted directional fans, 

the fans must be interchanged end-for-end. 

2. 

Replace single directional rotor fan with one for the 
opposite direction. 

3. 

Fans are bi-directional which allows motor rotation in 
either direction without mechanical modification. 

4. 

The single directional rotor fans must be interchanged 
end-for-end. 

 

It will be necessary to rebalance the rotor if the fans are 
changed. 

 

Accurate shaft alignment between motor and driven 
equipment is essential.  Improper alignment may result 
in vibration, bearing overloads and excessive shaft 
stresses.  Flexible couplings will not compensate for 
excessive misalignment. 
 

A basic rule is to not have more than five shims in a shim 
pack under any one motor foot. Thick shim packs 
consisting of many thin shims will cause soft foot, 
excessive vibration or twisted frame (motor foot out of 
plane). 

 
Parallel Alignment 
After positioning unit for correct end float, separate the 
coupling halves and mount a dial indicator rigidly on 
one coupling half with the button on the cylindrical 
surface of the other half.  Rotate the shafts together, 
and take readings at top, bottom and side positions.  
Align shaft so difference between top and bottom 
readings and the side readings is a maximum of   
0.002 inch for a flexible coupling.