Technical Specification As Per IS : 2705
Highest System Voltage( H.S.V.)
12 KV ( r.m.s.)
36 KV (r.m.s.)
Power frequency dry/ wet withstand voltage on primary winding for one minute
28 KV ( r.m.s.)
70 KV ( r.m.s.)
Lightning Impulse withstand Voltage ( 1.2 x 50 μs )
75 KV ( r.m.s.)
170 KV ( r.m.s.)
PD measuring Voltage / Permissible Voltage
Rated Transformation Ratio
As per customer requirement (in Amp.)
Rated Primary Current
Upto 2000 Amp.
Rated Secondary Current
1 Amp. 5 Amp. 0.577 Amp.
Short Time Thermal Current (Ith)
As per customer requirement.
In general CT is to be specified with STF of 100 for 1 Sec. or STC (lth) equal to the system fault level whichever is lower. KA ( r.m.s. )
5 to 3.0 Second
Short Time Dynamic Current
2.5 X Ith KA (Peak)
Number of Cores
Upto 3 cores
Upto 60VA, 0.8 pf Lagging
For Metering :
0.2S, 0.2, 0.5S, 0.5, 1.0 & 3.0.
5P, 10P, 15P & PS
IAF, ALF, Knee Point Voltage, Exciting Current & Resistance
As per customer requirement / Design Constraints
Type of construction
Epoxy Resin cast suitable for different panels.
Constructional / Salient Features
•Transformer is to be unpacked fully before carrying out site tests.
•Before energizing, all the secondary terminals not in use are to be short circuited and grounded. Primary connection is to be tightened sufficiently to avoid hot connection.