Siemens induction motors- generators cgii 用户手册

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Vibration 
Most problems can be detected when inspected 
visually.  Check for; 
 
1.  Loose or missing parts, such as fan blades, nuts, 

bolts, screws, couplings, etc. 

2.  Accumulation of dirt on fan or rotor. 
3. Associated 

equipment - Disconnect equipment to 

determine where the vibration is being generated. 

4. Foundation construction - Base, grouting and 

associated equipment supporting drives must be  
in good condition.  Vibration can be amplified by 
weak construction.  Vibration of base just below 
motor feet should not exceed 25% of motor 
vibration. 

5. History - When was vibration first noted?  Was 

there a change in loading and/or duty of 
equipment?  Has ambient vibration changed? 
 

More important than the actual vibration is the 
vibration change over a period of time. 
 

Two factors that require corrective maintenance are 
electrical failure or mechanical failure.  The first sign 
of electrical failure is usually low insulation 
resistance.  Mechanical failures are usually preceded 
by excessive bearing noise or heat. 
 
Low Insulation Resistance 
Factors that usually cause low insulation readings 
are: 
1.  Dirty windings (oil, dust, grease, salt, etc.). 
2. Excessive 

moisture. 

3.  Mechanically damaged insulation. 
4. Heat 

deterioration 

 
Dirty windings can be cleaned and moist windings 
dried; however, items 3 and 4 require extensive 
repairs by a certified service center. 
 

Flying dirt, dust or other particles. 
May cause eye injury. 
Wear safety glasses and dust mask when using 
compressed air. 

 

 
Cleaning 
Clean the inside and outside of the motor regularly.  
Actual conditions existing around the motor dictate 
the frequency of cleaning operations.  Use the 
following procedures as they apply. 

 

1.  Wipe off dust, dirt, oil, water, etc., from external 

surfaces of the motor. These materials can work 
into or be carried into the motor windings and 
may cause overheating or insulation breakdown. 

2.  Remove dirt, dust, or other debris from ventilating 

air inlets and exhausts.  Do not operate motor 
with air passages blocked or restricted. 

 

Remove rotor.  Inspect air vents and remove any 
obstructions. 

 

MICLAD™ form wound VPI (vacuum pressure 
impregnated) insulated coils may be cleaned with a 
quick drying solvent and lint free cloths or steam 
cleaned with low-pressure steam, then the entire 
stator oven baked at 200°F for 12 hours and then 
230°F for 12 hours. 

 

The stator winding insulation resistance should be 
measured before and after any cleaning operation. 

 

The windings may be cleaned with a solvent 
compatible with the insulation system and oven dried.  
Water and detergents with an oven drying cycle may 
be used as an alternate on MICLAD™ VPI insulation 
systems. 

 

MICLAD™ is a Siemens trademark. 

 

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

 

High Voltage. 
May damage semi-conductors, small transformers, 
voltage regulators, and other devices. 
Disconnect from circuit before testing insulation 
resistance.