Basler BE1-CDS220, Instruction Manual

Page: 131 / 476

BE1-CDS220 Reporting and Alarm Functions 6-13
CT CKT1: 0.87 @ 0 0.86 @ 240 0.86 @ 121
CT CKT2: 1.32 @ 211 1.29 @ 91 1.32 @ 332
ANGLE COMPENSATED I
CT CKT1: 0.87 @ 0 0.86 @ 240 0.86 @ 121
CT CKT2: 1.32 @ 181 1.29 @ 61 1.32 @ 302
TAP COMP I
CT CKT1: 0.28 @ 0 0.27 @ 240 0.27 @ 121
CT CKT2: 0.28 @ 181 0.28 @ 61 0.27 @ 302
IOP: 0.01 *TAP 0.01 *TAP 0.01 *TAP
SLOPE RATIO 4 % 4 % 4 %
The following differential check record example was developed from the same simulated substation but
has differential alarms caused by the angle compensation. This record shows a 60 degree error between
the compared phases (the angle should be 180 degrees). Notice that in the 87 Settings, the transformer
connection for CT circuit 1 is set to DAB. In trying to compensate for a 30 degree shift, the compensation
shifted the angle the wrong direction and created a 60 degree error. The connection should be DAC.
Example 2.
>RA-DIFF
CDS 220 DIFFERENTIAL CHECK RECORD
REPORT DATE : 11/10/98
REPORT TIME : 10:12:42.701
STATION ID : SIMULATED SUBST
RELAY ID : BANK-T1
USER1 ID : TEST1
USER2 ID : TEST1
RELAY ADDRESS : 0
ACTIVE GROUP : 0
87T SETTINGS CTR CT CON TX CON GROUNDED
CT CKT1 240 WYE DAB NO
CT CKT2 400 WYE WYE YES
MINPU 0.20 *TAP
SLOPE 25 %
ALARM 50 %
URO 6 *TAP
COMPENSATION Angle Tap
CT CKT1 WYE 3.12
CT CKT2 DAB 4.68
ALARMS PHASE A PHASE B PHASE C
DIFFERENTIAL: ALARM ALARM ALARM
POLARITY: OK OK OK
ANGLE COMP: ALARM ALARM ALARM
MISMATCH: OK OK OK
MEASUREMENTS PHASE A PHASE B PHASE C
MEASURED I PRI
CT CKT1: 206 @ 0 202 @ 240 204 @ 121
CT CKT2: 516 @ 211 508 @ 91 516 @ 332
MEASURED I SEC
CT CKT1: 0.86 @ 0 0.84 @ 240 0.85 @ 121
CT CKT2: 1.29 @ 211 1.27 @ 91 1.29 @ 332
ANGLE COMPENSATED I
CT CKT1: 0.86 @ 0 0.84 @ 240 0.85 @ 121
CT CKT2: 1.29 @ 241 1.27 @ 122 1.29 @ 2
TAP COMP I
CT CKT1: 0.27 @ 0 0.27 @ 240 0.27 @ 121
CT CKT2: 0.27 @ 241 0.27 @ 122 0.27 @ 2
IOP: 0.28 *TAP 0.28 *TAP 0.28 *TAP
SLOPE RATIO 104 % 104 % 104 %