Ct And Vt Ratio - GE MiCOM P40 Agile Technical Manual

Setting
MiCOM P40 Agile P442, P444
Menu text
CB CONTROL
'A/R Single Pole' and 'A/R Three pole' must be enabled for validating the autoreclose
function ("Autoreclose" menu, 1 pole (1P) and 3 poles (3P) cells.
If "three pole autoreclose (A/R TPAR Enable') or single pole autoreclose ('A/R SPAR
Enable') opto inputs are assigned in the PSL, these inputs have priority and will enable or
disable the single or three poles autoreclose function (regardless of the MiCOM S1 Agile or
front panel settings).
3.3

CT and VT ratio

Menu Text
CT AND VT RATIOS
Main VT Primary
Sets the phase Voltage Transformer input primary voltage rating.
Main VT's Sec'y
Sets the phase Voltage Transformer input secondary voltage rating.
4th VT Primary
Sets the 4th Voltage Transformer input primary current rating. This VT can be used either
for synchro-check or residual voltage measurement.
4th VT Secondary
Sets the Check Synchronisation Voltage Transformer input secondary current rating.
Phase CT Primary
Sets the phase Current Transformer input primary current rating.
Phase CT Sec'y
Sets the phase Current Transformer input secondary current rating.
MComp CT Primary
Sets the mutual compensation Current Transformer input primary current rating:
Analysis of an earth fault on one circuit of a parallel over-head line shows that a fault
locator positioned at one end of the faulty line will tend to over-reach while that at the other
end will tend to under-reach. In cases of long lines with high mutual inductance, mutual
zero sequence compensation can be used to improve the fault locator accuracy. The
compensation is achieved by taking an input to the relay from the residual circuit of the
current transformers in the parallel line.
This CT can be used either for mutual compensation or residual current measurement.
MComp CT Sec'y
Sets the mutual compensation Current Transformer input secondary current rating.
C/S input
The check synchronism VT input may be connected to either a phase to phase or phase-
to-neutral voltage and for correct synchronism check operation, the relay has to be
programmed with the required connection. The "C/S Input" setting should be set to A-N, B-
N, C-N, A-B, B-C or C-A as appropriate.
Default setting
Default Setting
110.0 V 100.0 V
110.0 V 80.00 V
110.0 V 100.00 V
110.0 V 100.00 V
1.000 A 1.000 A
1.000 A 1 A / 5 A
1.000 A 1.000 A
1.000 A 1 A / 5 A
A-N A-N / B-B / C-N / A-B / B-C / C-A
Setting range
Min Max
Setting Range
Min. Max.
1.000 MV
140.0 V
1.000 MV
140.0 V
30.00 kA
30.00 kA
P44x/EN ST/Hb6
(ST) 4-43
Step size
Step Size
1.000 V
1.000 V
1.000 V
1.000 V
1.000 A
1.000 A