Compare direct and Indirect method of testing.
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Sr No.
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Parameter
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Direct Testing
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Indirect Testing
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| 1 |
Nature of loading
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The m/c is actually loaded at full load.
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The m/c is not actually loaded but machine run on N.L.
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| 2 |
Suitability
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Suitable for m/c of low rating
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Suitable for m/c of high rating
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| 3 |
Power consumption
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In this testing large power is consumed
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In this testing small power is consumed
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| 4 |
Time period
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It requires more time
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It requires less time
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| 5 |
Calculation
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Calculations are less & Simple
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Calculations are more & complicated
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| 6 |
Accuracy
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This method gives the most accurate results
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This method gives less accurate result. The result obtained are either less or more than the actual
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| 7 |
Safety
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It is less safe as a high current actually flows through the circuit
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It is more safe as actual current does not flow through the circuit
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| 8 |
Assumption
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Generally no assumptions are made
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Generally some assumptions are to be considered
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| 9 |
Type of connections
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The connection are more and difficult
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The connections are less and Simple
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| 10 |
Equipment’s/ Apparatus
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It requires more number of equipment’s
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It requires less number of equipment’s
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| 11 |
Method of testing
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This is simple
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This is complicated
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| 12 |
Technical Skill
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The technical skill and knowledge is must but it is less required.
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The technical skill and knowledge is must but it is more required.
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| 13 |
Space required
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Space required is more
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Space required is less
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| 14 |
Location
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It is suitable for indoor testing i.e. in industry or lab
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It is suitable for outdoor testing i.e. on the site
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| 15 |
Example
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1.With the help of rake arrangement, 2. Coupling a machine to its shaft for loading purpose.
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1.O.C. and S.C test on transformer/Alternator / I.M. , 2. Swinburne test on DC machines.
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