Alstom MiCOM P54 Series - 1.3.12 Sensitive earth fault

P54x/EN ST/La4 Settings
(ST) 4-38 MiCOM P543, P544, P545, P546
ST
1.3.12 Sensitive earth fault
If a system is earthed through a high impedan subj high ground fault
ul l be severely l Conseq , the app th fault
prote both a priate characte d a su ensitive range
s provided within
his pu , which has a dedi d input.
ce, or is ect to
resistance, the earth fa
ction requires
t level wil
n appro
imited.
ristic an
uently
itably s
lied ear
setting
in order to be effective. A separate four-stage sensitive earth fault element i
the P54x relay for t rpose cate
Setting range
Menu text Default setting Step size
Min. Max.
Sens E/F Options SEF SEF Enabled, Wattmetric SEF
Setting to select the type of sensitive earth faul
impedance function to be used.
t protection function and the type of high-
SEF>1 Function
DT
Disabled, DT, IEC S Inverse, IEC V
Inverse, IEC E inverse, UK LT Inverse
IEEE M Inverse, IEEE V Inverse, IEEE E
Inverse, US Inverse, US ST Inverse, IDG
Setting for the tripping c eristic for the firs sensitive earth fault element. haract t stage
SEF>1 Direction
Non-directional
Non-directional
Direction Fwd
Direction Rev
N/A
This setting determines the direction of measurement for the first stage sensitive earth
fault element.
SEF>1 Current 0.05 x n
SEF
0.005 x
n
SEF
0.1x n
SEF
0.00025 x
n
SEF
Pick- r the first arth fault eup setting fo stage sensitive e lement.
SEF>1 IDG Is
1.5 1 4 0.1
This setting is set as a of SEF> se rve (Scan an) and
h the element starts.
multiple tting for the IDG cu dinavi
determines the actual relay current threshold at whic
SEF>1 Delay
1 0 200 s 0.01 s
Setting for the time delay for the first stage definite time element.
SEF>1 TMS
1 0.025 1.2 0.005
Setting for the time multiplier to adjust the operating time of the IEC IDMT characteristic.
SEF>1 Time Dial
1 0.1 100 0.1
Setting for the time multiplier to adjust the operating time of the IEEE/US IDMT curves.
SEF>1 Reset Char.
DT DT or Inverse N/A
Setting to determine the type of reset/release characteristic of the IEEE/US curves.
SEF>1 tRESET
0 0 s 100 s 0.01 s
Setting to determine the reset/release time for definite time reset characteristic.
SEF>1 IDG Time
1.2 1 2 0.01
Setting for the IDG curve minimum t high le t
curre
used to set the operating time a vels of faul
nt.
SEF>2 Cells as for
ISEF>1 Above
SEF>3 Status
Disabled Disabled or Enabled N/A
Setting to enable or disable the third stage definite time sensitive earth fault element.