Non-Directional Elements; Earth Fault Protection; Directional Elements; Sef Protection (Residually Connected) - GE P24DM Technical Manual

P24xM
2.1.2

NON-DIRECTIONAL ELEMENTS

Time-delayed phase overcurrent elements
I
cp
(
V = R +
K CT
2
Instantaneous phase overcurrent elements
= ( +
V I R
K sp CT
2.2

EARTH FAULT PROTECTION

2.2.1

DIRECTIONAL ELEMENTS

Instantaneous earth fault overcurrent elements
I
fn
= ( +
V R
K CT
2
2.2.2 NON-DIRECTIONAL ELEMENTS
Time-delayed earth fault overcurrent elements
I
cn
= ( +
V R
K CT
2
Instantaneous earth fault overcurrent elements
V = I ( R +
K sn CT
2.3

SEF PROTECTION (RESIDUALLY CONNECTED)

2.3.1 DIRECTIONAL ELEMENTS
Time delayed SEF protection
I
≥ +
cn
(
V R
K CT
2
Instantaneous SEF protection
I
≥ +
fn
V ( R
K CT
2
P24xM-TM-EN-2.1
)
R + R
L p
+ )
R R
L p
2 + + )
R R Rn
L p
2 + + )
R R R
L p n
2 R + R + R )
L p n
+ +
2 )
R R Rn
L p
+ +
2 R R Rn )
L p
Chapter 9 - Current Transformer Requirements
195