why is the vector group analysis done in transformer tests

Answer Posted / fred jabagat

Vector Group can be used as basis in setting the phase
compensator factor for numerical transformer differential
relays, i.e. SEL387.
A 3-Ph Transformer is wired internally in different ways to
produce a desired phase position between primary and
secondary terminals.
IEC standards develop a transformer circuit configuration
and a corresponding vector group code which follows a clock
that represents a 30 degrees shift in every hour.
The CT's of a numerical transformer differential relays are
usually wired with its polarity mark facing away from the
protected winding. Because of the phase shift between the
primary and secondary terminals of the transformer it is
necessary to set a phase compensator factor to the
differential relay so that it will not trip on normal load.

Is This Answer Correct ?    38 Yes 6 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

What will happen if we on 200kvr capacitor bank(11kv in bus)If there is low load on transformer (1.5 mva 33/11 kv)

1128


Why saturation region slowly shifted in the left side?

1459


please give some hindalco placement papers for written exam

1354


why we cannot protect 100% winding of an alternator by using differential protection?

1748


how can calculate resistance box for 15 kw, 6 pole, RV-230, RA-42 motor

2891






diameter of cable and core is doubled then the value of capacitance is

3704


why +24 v and -48 v give to BTS? If -48v protect from surge then why we not use -24 v?

1424


Instrument connected to a single phase supply

1257


how does the thyistor work in dc drive?

1556


why should the primary of transformer be connected in delta in a heat run test?

1472


What is cathode ray oscilloscope (cro)?

684


WHAT IS THE MEANING OG (li = 7 In)

1537


What does bode plots shows?

681


what will be d.g. capacity to cater together for 14hp A.C. load & 3kw lighting load

1557


what is the difference between c power and U power acb breaker

5288