Selection of Insulating Material Practical

Selection of Insulating Material Practical 
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Practical Significance

The identification and selection of proper insulating materials is required for safe working of electrical appliances. The insulating material separates the electrical conductors to safeguard individuals from electrically energized parts.


Competency and Practical Skills

This practical is expected to develop the following skills for the industry identified competency: ‘Plan wiring/cabling activities using relevant materials following safe practices’

i. Identify various insulating materials

ii. Select proper insulating material as per class of insulation.


Practical Outcome

1. Select insulating materials for specific applications from given samples (at least five).


Relevant Affective domain related Outcome(s)

i. Practice good housekeeping with safety measures.

ii. Demonstrate working as a leader/a team member.

iii. Maintain tools and equipment.

iv. Follow ethical practices.


Minimum Theoretical Background

Insulating material is generally used as a protective coating on electrical conductor and cables. e.g. polyethylene, cross linked polyethylene-XLPE, polyvinyl chloride-PVC, Teflon, silicone etc. Bushings are made insulating material like glass, porcelain, or composite polymer materials.


Transformer oil is widely used as an insulator to prevent arcing in transformers, stabilizers, circuit breakers, etc. The insulating oil can withstand insulating properties up to a specified electrical breakdown voltage. Vacuum, gas (sulfur hexafluoride), and ceramic or glass wire are other methods of insulation in high voltage systems. Small transformers, power generators, and electrical motors contain insulation on the wire coils by the means of polymer varnish. Fiberglass insulating tape is also used as a winding coil separator.


All domestic electrical appliances are insulated to prevent their user from electrical shock hazard. Mica, fiberglass, porcelain, backelite etc. are used in domestic appliances.

Insulation table made of PVC, nylon, fiberglass cloth are used to insulate wires and cables.


Resources Required

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Precautions to be followed

1 Observe the samples carefully.

2 In case of any doubt, ask teacher.


Procedure

1. Pick any one sample of insulating material.

2. Observe the sample carefully.

3. Identify the material.

4. Write its properties. (as mentioned in references).

5. Select the material for proper application and write the application in observation space.

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