Protection Engineering Basics and Schemes Protection Engineering | Page 200

Due to different CT ratio on both side of transformer we
used Interposing CT; interposing CT corrects ratio and
Phase errors. Matching factor is term used for different
ratio CTs currents comparison in differential protection
for transformer.
6.3.1.1 Differential Relays application:
First application we will discuss is busbar Differential
protection.
Rule is same, current in to feeder from source is equal to
current exist from feeder to load on bus.
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