State the insulating materials used in motor. Write temperature class and withstand temperature ranges for them.

State the insulating materials used in motor. Write temperature class and withstand temperature ranges for them. 
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1 Answer

Answer :

The insulating materials used in motor are as belows:


1. Cotton,

2. Silk, or paper,

3. Press board,

4. Resins

5. PVC

6. Cellulose-Fiber,

7. Enameled coating, etc 


Insulation Classes
Maximum permissible temperature (°C)
Materials 
Class-Y 
90°
cotton, silk, or paper, press board, vulcanized fiber, wood, celluloseFiber, PVC VIR etc without impregnating substance
Class- A 
105°
cotton, silk, or paper, press board, vulcanized fiber, wood, with impregnated varnish or insulation oil
Class- E 
120°
Superior wire enamels based on polyvinyl ferrul or epoxy resins, moudling with cellulose fibers, cotton fabric and paper laminates. 
Class- B 
130°
Glass fiber, asbestos, Mica, Varnished glass fiber textile, built up mica
Class- F
155°
adhesives, silicone, and alkyd-resin varnish of higher thermal endurance and: Glass fiber, asbestos, Mica, Varnished glass fiber textile, built up mica
Class- H
180°
Combination of materials such as mica, glass, fiber, asbestos, with suitable high resistive bonding material like silicon
Class- C
Over 180°
Mica, porcelain, ceramics, glass quartz, asbestos, treated glass fiber or treated asbestos. etc.
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