Electrical Engineering - Three-Phase Systems in Power Applications - Discussion

Discussion Forum : Three-Phase Systems in Power Applications - General Questions (Q.No. 9)
9.
A two-phase generator is connected to two 90 load resistors. Each coil generates 120 V ac. A common neutral line exists. How much current flows through the common neutral line?
1.33 A
1.88 A
2.66 A
1.77 A
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
63 comments Page 2 of 7.

NASR said:   10 years ago
Right answer is D because:

1 = 120/90a with angle 0+120/90 with angle 120.

= 1.33+j0-0.665+j1.152.

Chandrima said:   10 years ago
Answer should be 1.88 amp.

V/i = 1.33 amp, current flowing through neutral 2*1.33 = 2.66, but RMS value of the current will be 2.66/sqrt2 = 1.88 amp.

Vjagannadharao said:   10 years ago
Resistance will be 45.

And I = V/R.

V = 40, i = 120.

I = 120/45 = 2. 66 A a write method.

Current neutral wire is 1.33+1.33 = 2.66 A.

Then I = V/R = 2.66 A.

Aditya bakshi said:   9 years ago
I think the answer is c, if the answer is D please give me the correct explanation.

Somnath said:   1 decade ago
I think it's 2.66.

2 phase generator. So connect load of 2*90 ohm resistance in parallel.

Resultant resistance will be 45.

Then I = V/R.

= 120/45 = 2.66 A.

Manivel said:   1 decade ago
Consider two coils which are connected to the terminals A and B respectively. The other end of the coils terminated in neutral point N.

Since, Emf generated in each coil is 120 then current Ian (flows from A to N) = 1.33(120/90) and Ibn = 1.33(120/90).

Hence, the current in neutral wire is 1.33+1.33 = 2.66 A.

KeerthiRaj said:   1 decade ago
@Mr Parveen Kumar and Mr Sandeep Wasnik:

Although your ideas were wrong, but I think you people even don't know how to calculate phase to phase voltage, if you don't know please keep quiet, don't post wrong things.

Sayed Tousif Pasha said:   1 decade ago
Whether the load is in series or parallel.

Hami said:   1 decade ago
I think 1.88 A is right answer. Because there is common neutral wire which means 1.33 A. After multiplying with 1.141, we get 1.88 A.

Rachappa said:   9 years ago
Is there any formula to find this answer?


Post your comments here:

Your comments will be displayed after verification.