Trusted by millions of Kenyans
LoginRegister
Study resources on Kenyaplex

Get ready-made curriculum aligned revision materials

Exam papers, notes, holiday assignments and topical questions – all aligned to the Kenyan curriculum.

Browse exam papers
Or go directly to:
Class notes Holiday assignments Topical questions Other resources

A short circuit fault is located by varley loop test. The ratio arms are set at P=5 ohms and Q=10 ohms and the values of...

A short circuit fault is located by varley loop test. The ratio arms are set at P=5 ohms and Q=10 ohms and the values of variable resistance S are 16 ohm for position 1 of switch K and 7 ohms for position 2.The sound and the faulty cables are identical and have a resistance of 0.4 ohms/Km. Determine the length of each cable and the distance of fault from the test end.

Answers

Kevin
Let S1 be the value of resistance for position 1 and S2 for position 2.
Therefore,[R+X]/S1=P/Q.
Hence the resistance of loop R+X=[P/Q]*S1=[5/10]*16=8 ohms
Resistance of each cable =8/2=4 ohms.
Length of each cable=4/0.4=10 km.
At postion 2 we have;R/[X+S2]=P/Q.
[R+X+S2]/[X+S2]=[P+Q]/Q OR [8+7]/[X+7]=[5+10]/10.
X=3.0 ohms.
Dstance of fault from test end=3/4=7.5 km
Kevinsenzoochieng answered the question on October 22, 2019 at 08:02

Answer Attachments

Next: (a) Explain the importance of the high percentage of nitrogen in air(b) Why is nitrogen used for storage of semen in artificial insemination?

Previous: The diagram below is used in preparation of a gas in the laboratory. Answer the questions that follow;

View more Engineering Questions and Answers  |  Return to Questions Index

Exams With Marking Schemes

Related Questions