Toshiba GR200 Series Instruction Manual page 439

Metering information on the screen
The user can examine the metering data on the IED screen; Figure 8.3-1 illustrates the
information about currents. The values of the differential currents are displayed in DIFCH
and DIFZA–DIFZF; and these values are displayed in percent (%) as a percentage of the
DIFCH and DIFZA–DIFZF settings. The phase angles are also displayed; these are shown
with reference to the positive-sequence voltage (V1). When the angle is leading the reference
signal, it is displayed as a plus (+).
If there is no voltage input, the phase-A current flowing in CH1 is used as the reference
signal. Therefore, it is recommended that CH1 should be assigned to a feeder. If the current in
CH1 is insufficient to be used as the reference signal, the current of the closest CH (that is,
CH2) is used as the reference signal.
The user can examine the data described above (except for the phase differential
currents) based on either the primary side or the secondary side of the CT; the selection of the
CT primary or secondary side is made by setting. To display the values accurately, the user
should set the values of CT ratio correctly.
Figure 8.3-1 Current meter on the IED screen
Note: If any quantity does not enter to the VCT, the value on the screen is displayed
such as "***.**" and "–––––".
Setting for measurements
Selecting either primary/secondary values
(i)
In the8.4 metering function, the value at the primary side is displayed on the screen; the value
will be displayed in kV-unit when the value is larger than 1000 volts. When wishing to display
the value at the secondary side, the user should set Secondary for the setting
[Display_Value].Table 8.4-1 shows the effective digit when Secondary is set.
Metering
10:48 1/311
Ida
12.345kA 1234.5%
Idb
12.345kA 1234.5%
Idc
12.345kA 1234.5%
- 425 -
6F2S1931 (0.20)
Centralized GRB200
(Soft: 030, 031, 032, 033, 034)