What are the advantages of Hopkinsons test?

What are the advantages of Hopkinsons test?

This test can be done under full-load conditions so that a rise in temperature & commutation can be examined. Iron loss change because of flux distortion is taken into account because of the full-load condition. Efficiency can be determined at dissimilar loads.

What are the advantages and disadvantages of Hopkinson’s test?

Disadvantages of Hopkinson’s Test It is difficult to find two identical machines needed for Hopkinson’s test. Both machines cannot be loaded equally all the time. It is not possible to get separate iron losses for the two machines though they are different because of their excitations.

What are the advantages and disadvantages of Swinburne test?

The main advantages of this test are: This test is very convenient and economical as it is required very less power from supply to perform the test. Since constant losses are known, efficiency of Swinburne’s test can be pre-determined at any load.

What are the advantages of Hopkinson’s test over Swinburne’s test?

The method of testing is very economical since large machines can be tested at full-load with small power. Since the test is at full-load, it overcomes the drawback of change in iron losses when machines are loaded due to armature reaction in Swinburne’s Test.

Why Swinburne’s test is called indirect test?

The Swinburne test is an indirect method for determining the efficiency of DC motors. It works by finding the no-load losses experimentally and then estimating additional losses from the rated motor data. From this information, the efficiency can be determined at any applied load.

Why do we conduct Sumpner’s test?

Explanation: Sumpner’s test is used to determine the effect of transformer on loaded condition. Thus, two transformers are tested simultaneously, where one simply acts as a load to another transformer. Primaries of both of the transformers used in a test, are connected in parallel with each other.

What will happen if field current of generator in Hopkinson’s test is increased?

Explanation: If field current through generator is increased, back emf of generator will increase thus it’ll become greater than back emf of a motor, so to compensate this effect armature current in generator will increase thus, motor armature current will also increase.

Why Swinburne’s test is called No load Test?

Due to armature reaction flux is distorted at full load and, as a result, the iron loss is increased. As the Swinburne’s test is performed at no load. Commutation on full load cannot be determined whether it is satisfactory or not and whether the temperature rise is within the specified limits or not.

Why Swinburne’s test is used?

Why Sumpner’s test is used?

What are the advantages and disadvantages of Swinburne’s test?

Swinburne’s Test 1 Efficiency when the machine is running as a Motor. The efficiency of the motor is given below. 2 Efficiency when the machine is running as a Generator. 3 Advantages of Swinburne’s Test. The power required to test a large machine is small. 4 Disadvantages of Swinburne’s Test. 5 Limitations of Swinburne’s Test.

What kind of test is the Hopkinson test?

Hopkinson’s Test is also known as Regenerative Test, Back to Back test and Heat Run Test. In Hopkinson Test, two identical shunt machines are required which are coupled both mechanically and electrically in parallel. One is acting as a motor and another one as a generator.

How is the Swinburne’s test used in DC machines?

Using the Swinburne’s test, the losses occurred in DC machines can be calculated with no-load power. Since DC machines are nothing but motors or generators. This test is applicable only for the large shunt DC machines which have constant flux. It is very easy to find the efficiency of the machine in advance.

How are shunt machines used in Hopkinson test?

In Hopkinson Test, two identical shunt machines are required which are coupled both mechanically and electrically in parallel. One is acting as a motor and another one as a generator.