1)Why potential transformer primary site grounded?
2)can be loop between neutral & body for grounding?
3)What is the difference between ELCB &RCCB?
4)Why we use iron core in transformer insted of wooden core?
5)what is the principle of excitation?
6)Why we test the core balance test for transformer?
7)what is creepage?What is the creepage length for
insulators at different voltages?
8)How much type of relays used for differential protection
of generator,transformer & busbar protection?

Answer Posted / abcd

ELCB detects phase to earth faults.It can detect low impedence faults but on the contrary if there occurs a high impedence fault in the system then the fault current may be very small. Such faults are detected by RCCB.

Is This Answer Correct ?    0 Yes 0 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

What is measurement?

757


What is marx circuit?

658


Application Comparison between 22KV (UE)and 33KV (E) system. Are we allowed to use 33KV (E) cable in lieu of 22KV (UE) cable. What are the technical disadvantages.

1847


What is the loss of power of transformer 220kv/33kv,63/80mva of % imp12.05 at 80%load

1401


How the frame size of a flange mounted AC induction motor is calculated?

1524






solor panels arrange some angle,panel is flat fitted energy was produced or not why?

1416


what's prime importance of protection in electrical system.if protection system don't work properly what can happen in electrical system?

1441


How can eliminate noise problem inside temperature controller temp. variation due to contactor chattering problem.

1192


what is the voltage regulation for unity and zero power factor?

1766


In ups static switch if i gives the supply at output end it will open the circuit in stactic switch or not if it will open then how it operates.

1855


sir please send me techinical questions for junior engineer posting in bangalore railway i am diploma holder

1557


where was current transformer protection units used and why??

1549


Is it possible to measure correct value of earth resistance & cable insulation ristance with out disconncting earth lead & both sides of cable ends? If not, any other method to measure ER & CIR with out disconneting from the system.

1659


hi frenz,its aswathy.i hve aplied for the hpcl test on feb,pls send the test patern & the placement papers as soon as possible. mail-id :kjaswathy@gmail.com

1317


How to Calculate Transformer Earthing Electrode Rod Size both Body and neutral Earthing ? Any Standard Formula? Please Suggted

1152