Why we use two wattmeter during block rotor test and no load test of 3phase in

Why we use two wattmeter during block rotor test and no load test of
3phase induction motor? And how can we understand the neat power
requirement of from this test?

Question Posted / rajorshi

2 Answers
10705 Views
I also Faced
E-Mail Answers

Answers were Sorted based on User's Feedback

Why we use two wattmeter during block rotor test and no load test of 3phase induction motor? And h..

Answer / k,prakashchandra

As the pf is very low, one of the 3 watt meters will show
negative reading

Is This Answer Correct ?

7 Yes

1 No

Why we use two wattmeter during block rotor test and no load test of 3phase induction motor? And h..

Answer / natchi

In this test, we use two single phase wattmeters or one 3phase wattmeter, during test one of the 1phase wattmeter reads positive value and other one reads negative value of 3 phase power.

but in usage of 3 phase wattmeter gives directly the whole power of 3 phase supply.

Is This Answer Correct ?

8 Yes

4 No

Post New Answer

More Electrical Engineering Interview Questions

what is the difference between multimeter and megger?

3 Answers Bhel, Metro,

i want prepare power grid exam what are book we want refer for electrical ?

5 Answers

Why need 3phase machine double earthing?

0 Answers

What is on delay and off delay timers

1 Answers NCC,

SUPPOSE A CIRCUIT BREAKER HAS TRIPPED THE THE LINE WHEN A FAULT OCCUR ON IT.NOW WHEN THE FAULT HAS BEEN CLEARED, HOW THE CIRCUIT BREAKER WILL CLOSE AUTOMATICALLY NOT MANUALLY.

6 Answers Bureau of Energy Efficiency, DVC,

15 kva dg set single phase takes 63amp( approximate) while same rating 15kva three phase takes 35amp approximate. why ? and what will be per phase current for 15 kva

2 Answers TVI,

who is invented transforner (230v).......

2 Answers

How to configure the drives in PLC, through Profibus commnication. And to how to address it?

0 Answers

i want to know is it possible to generate usefull power by coupling generator with motor & supply gives to motor by battery source then generator generates power. remove the battery source given to the motor & feed the supply from some of the generated power supply to the motor & motor runs continously. generator generate power contnously.is it possible ?

5 Answers UltraTech,

What willbe change in programming when we use 5/3 solenoid inplace of 5/2 in operating of a cylinder?

0 Answers ITC Infotech,

The power showed in the name plate of the motor is input power or output power?? The power showed in the name plate is 18.5kw measured current is 34.5 amps. location is india. can i calculate the efficiency of the motor using this data??

2 Answers

what is oti and wti

3 Answers Jindal,

For more Electrical Engineering Interview Questions Click Here