Page 141 - intelligent encyclopedia ( equipment issue 1 )

intelligent
TRANSFORMERS

• Arrangements of changing the loading percentages on the load

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Transformer’s iron core

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• The iron core should be treated after collection by some layers of paint to protect it from corrosion

Windings (coils)

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Penetration isolators
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Percentage of the transformer's impedance
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er's components.

Table (5/ 5- 6): the maximum allowed values for the temperature increase
for the transformer's parts above the ambient temperature 40 Co

Degree of the windings Temperature of the di- The maximum allowed
parts of the transformer
isolation electric system (Co) temp. increase (Co)

Class A 105 Co 60 Co
Class E 120 Co 75 Co
Class B 130 Co 80 Co
windings
Class F 155 Co 100 Co
Class G 180 Co 125 Co
Class C 220 Co 150 Co
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and the nearby parts
to the iron core or any other
part of the transformer