Advantages of Swinburne's Test
The main advantages of this test are :
1.This test is very convenient and economical because the power required to test a machine is small.ie,only no load input power.
2.Efficiency can be pre-determined at any load because constant losses are known.
Disadvantages of Swinburne's Test
The main disadvantages of this test are :
1. Iron loss is neglected though there is change in iron loss from no load to full load due to armature reaction.At full load ,due to armature reaction ,flux is distorted which increase the iron loss in some cases by as much as 50%.
2. We cannot be sure about the satisfactory commutation on loaded condition because the test is done on no-load.
3. We can’t measure the temperature rise when the machine is loaded. Power losses can vary with the temperature.
4. In dc series motors, the Swinburne’s test cannot be done to find its efficiency as it is a no load test.Because in the case of dc series motors the speed is variable,when load increases speed decreases and when load decreases speed increases.hence at no load condition the speed will be extremely high.So this test cannot be applied to dc series machines.
The main advantages of this test are :
1.This test is very convenient and economical because the power required to test a machine is small.ie,only no load input power.
2.Efficiency can be pre-determined at any load because constant losses are known.
Disadvantages of Swinburne's Test
The main disadvantages of this test are :
1. Iron loss is neglected though there is change in iron loss from no load to full load due to armature reaction.At full load ,due to armature reaction ,flux is distorted which increase the iron loss in some cases by as much as 50%.
2. We cannot be sure about the satisfactory commutation on loaded condition because the test is done on no-load.
3. We can’t measure the temperature rise when the machine is loaded. Power losses can vary with the temperature.
4. In dc series motors, the Swinburne’s test cannot be done to find its efficiency as it is a no load test.Because in the case of dc series motors the speed is variable,when load increases speed decreases and when load decreases speed increases.hence at no load condition the speed will be extremely high.So this test cannot be applied to dc series machines.
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