Protection Engineering Basics and Schemes Protection Engineering | Page 35

 Multicore
 Multi ratio or Dual Ratio
1.1.12.1 Multi core:
This CT is CT with separate secondary windings , in which
if you are using one secondary winding you need to short
all other secondaries , because each core is act as
separate CT, it is represented in terms of primary like
4000/2000/1. In it if you are using 4000/1 then you must
have to short 2000/1 secondary contacts.
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