B.tech Examination papers dec 2014
sub - Switchgear and protection
Utu previous year question papers
uttarakhand technical university previous question papers
Time : 3 hrs
Q1: Attempt any four :
- Explain static relay and write its merits and demerits.
- Explain electromagnetic impedance relay.
- What are the various types of over current relays? Discuss their are of applications.
- Explain Directional Over-current relay?
- The current rating of a relay is 5A. PSM=2, TSM=0.3, CT ratio=400/5, fault current= 4000A. Determine the operating time of the relay. At TMS= 1, operating time various PSM are:
PSM= 2 4 5 8 10 20
operating time in seconds= 10 5 4 3 2.8 2.4