GE P24DM - Figure 37: Directional Angles

The directional criteria with residual voltage polarisation is given below:
Dir
ectional forward
(Ð VN + 180°) + RCA - 90° + (180° - tripping angle)/2 < Ð IN < ( Ð VN +180°) + RCA +90° - (180° -
tripping angle)/2
Directional reverse
(Ð VN + 180°) + RCA - 90° - (180° - tripping angle)/2 > Ð IN > ( Ð VN +180°) + RCA +90° + (180° -
tripping angle)/2
This can be best visualised with reference to the following diagram:
V00748
VN
VN
IN
Figure 37: Directional angles
Some of the models deriv
e the Residual Voltage quantity internally, from the 3-phase voltage input supplied from
either a 5-limb or three single-phase VTs.On models with 4th VT input, this feature can be used for Check Sync or
to measure the Residual Voltage VN. The 4th VT input can be configured for measured or derived voltage.
Chapter 6 - Current Protection Functions P24xM
112 P24xM-TM-EN-2.1