/PERATING INSTRUCTIONS
3$
6
# ' #
4ESTING THE DIFFERENTIAL PROTECTION
&OR TESTING THE DIFFERENTIAL PROTECTION THIS FUNCTION
MUST HAVE BEEN PARAMETERIZED AS OPERATIVE IE
$)&& 02/4
/.
OR $)&& 02/4
",/#+ 42)0 2%,
UNDER ADDRESS 4HE PILOT WIRE MONITORING IS
SWITCHED OFF ADDRESS 0),/4 -/.
/&&
7HEN TESTING AN INDIVIDUAL UNIT THE PILOT WIRES TERMI
NALS CAN BE SHORTCIRCUITED
7HEN TESTING TWO UNITS THE PILOT WIRES ARE CON
NECTED CROSSWISE BETWEEN THE RELAY PAIR "OTH UNITS
MUST BE CONNECTED TO THE AUXILIARY VOLTAGE )N THIS
CASE THE SECOND UNIT CAN RUN WITHOUT A TEST CURRENT
THUS SIMULATING A LINE SHORTCIRCUIT WITH SINGLEEN
DED INFEED OR THE TEST CURRENT IS INJECTED INTO BOTH
UNITS EITHER IN PHASE INTERNAL SHORTCIRCUIT OR IN
PHASE OPPOSITION EXTERNAL SHORTCIRCUIT
4HE FOLLOWING DESCRIPTION REFERS TO TESTING AN INDIVID
UAL UNIT WITH THE PILOT WIRE TERMINALS CONNECTED TO
EACH OTHER VIA A RESISTOR OF APPROX
¬
)T IS FUR
THER ASSUMED THAT THE PARAMETERS CONCERNING THE
PILOT WIRE CHARACTERISTICS HAVE BEEN LEFT IN THE POSI
TION AS DELIVERED IE RESISTANCE 2X
¬
ADDRESS
AND CAPACITANCE #X N& ADDRESS )N
CASE THE RELAY IS CONFIGURED FOR THREETERMINAL LINES
THEN ADDITIONALLY ADDRESS 2Y
¬
AND
#Y N&
7HEN ASSESSING THE CURRENTS IT MUST BE CONSIDERED
THAT THE CURRENT WHICH IS EVALUATED BY THE RELAY DE
PENDS ON THE CONNECTION MODE OF THE INPUT WINDINGS
OF THE SUMMATION TRANSFORMER AS WELL AS ON THE SET
TING PARAMETERS AND REFER TO 3ECTION
!DDITIONALLY ALL TEST CURRENTS MUST BE SINUSOI
DAL INJECTED CURRENTS
4HE FOLLOWING APPLIES
)
0
)
-
|
.
-4
|
.
PAR
WHERE
)
0
TEST CURRENT
)
-
MIXED CURRENT AS IT IS EVALUATED BY THE
RELAY
.
-4
FACTOR CAUSED BY THE MODE OF CONNECTION
OF THE SUMMATION MIXING TRANSFORMER
.
PAR
FACTOR CAUSED BY PARAMETER SETTING
.
-4
EQUALS FOR INJECTION OF THREEPHASE SYMMETRI
CAL CURRENTS AND STANDARD CONNECTION ACCORDING TO
&IGURE WHEN THE RELAY IS DELIVERED .
PAR
EQUALS
EITHER
4HE FACTORS .
-4
ACCORDING TO 4ABLE ARE VALID FOR
SINGLEPHASE INJECTED CURRENTS DEPENDENT OF THE FED
WINDINGS OF THE SUMMATION TRANSFORMER
7INDING
WEIGHTING
#ONNECTION
SURFACE MOUNTING
#ONNECTION
FLUSH MOUNTING
.
-4
ALL IN SE
RIES
4ML
4ML
4ML
4ML
BRIDGED
&
&
&
&
%
%
&
%
& &
& %
BRIDGED
4ABLE
#URRENT FACTORS OF SUMMATION TRANS
FORMER
4HE PARAMETER FACTOR CAN BE DERIVED FROM
.
PAR
)
. LINE
)
. CT
WHERE
)
. LINE
THE PRIMARY RATED CURRENT OF THE LINE AS
SET UNDER ADDRESS
)
. CT
THE PRIMARY RATED CURRENT OF THE MAIN
CTS AS SET UNDER ADDRESS
#AUTION
4EST CURRENTS LARGER THAN TIMES )
.
MAY
OVERLOAD AND DAMAGE THE RELAY IF APPLIED
CONTINUOUSLY REFER TO 3ECTION FOR
OVERLOAD CAPABILITY /BSERVE A COOLING
DOWN PERIOD
4HE LIMITS OF THE THERMAL CAPABILITY MUST BE OBSERVED
FOR THE INPUT WINDINGS OF THE SUMMATION TRANSFORMER
AS WELL AS FOR ITS OUTPUT CURRENT 7HEN DURING SINGLE
PHASE CURRENT TEST THE WEIGHTING FACTOR IS HIGHER
THAN THE PERMISSIBLE CURRENT IS REDUCED BY THE FAC
TOR .
-4
4ABLE BUT THE PERMISSIBLE CURRENT IS NOT
INCREASED WHEN ONLY ONE WINDING WEIGHTING IS USED
&EED A TEST CURRENT )
0
TIMES THE SETTING VALUE
) $)&& ADDRESS AND TIMES THE SETTING
VALUE ) 2%,%!3% ADDRESS BOTH PARAMETER
VALUES MUST BE EXCEEDED 4HE DIFFERENTIAL PROTECTION
PICKS UP ,%$ AT DELIVERY AND TRIPS ,%$ AT DELIV
ERY #HECK THAT THE ASSOCIATED TRIPPING AND SIGNAL
LING CONTACTS CLOSE
)F A TRIP DELAY HAS BEEN SET ADDRESS THEN THE
TRIP SIGNAL APPEARS CORRESPONDINGLY DELAYED
Summary of Contents for 7SD502
Page 148: ... PPENDIX 3 6 PPENDIX ENERAL DIAGRAMS ONNECTION DIAGRAMS 4ABLES ...
Page 176: ... 3 6 ...