ADR244A
Doc ID: ADR244A/PC/01
Rev No.: 01
Page No.: 4 of 15
independently settable with inverse time or
definite time characteristic. The following
tripping characteristics are available;
IEC/IEEE Inverse curves for tripping of over current
elements
ADR244A relay provides the inverse time
dropout characteristic (electromechanical
relay reset) for IEEE curves. The output of
protection function shall be reset after
dropout time delay.
ADR244A relay provides two stages of
definite time/inverse time internally derived
zero sequence over current (3I0>) protection
to detects asymmetrical faults in electrical
network. It can apply to over head
transmission line, underground cable, and
feeder. The ground current (3I0>) calculated
from three line currents.
Internally derived residual over current application
ADR244A relay provides two stages of
externally ground over current protection.
ADR244A relay measures ground fault
current through neutral CT input. Externally
ground CT input can also apply for high
impedance restricted earth fault protection or
sensitive ground fault protection through
CBCT.
Externally measured ground over current through neutral
CT
