Toshiba GR200 Series Instruction Manual page 81

the high-impedance; the user should set the same value for the [DIFGL-I] at all terminals.
When the terminals do not have an identical CT ratio, the user should set respective values so
that the DIFGL characteristics on the primary side are coordinated.
Setting DIFL-IDSV monitor
(iv)
When the differential current monitoring function is used, the setting [DIFL-IDSV] should be
determined using equation (2.5-2) by considering a maximum erroneous differential current
(Ierr) except the occurrence of a fault.
where,
Ierr: Maximum erroneous differential current
K: Setting margin (K= 1.2 to 1.5)
The user does not need to consider the condition relating to the charging current because
the function of charging-current compensation can operate.
The user should set the same value for the setting [DIFL-IDSV] for all terminals. When
the terminals do not have an identical CT ratio, the user should set respective values so that
the Id monitors on the primary side are coordinated.
Setting DIFL-IcC compensation
(v)
The user should set an internal charging current (Ic) and a rated power system voltage (V) for
the [DIFL-IcC] and the [DIFL-Vn]; the user can measure the charging current (Ic) using a
protected line being energized and another line being open.
If the power system has different rated voltages (V), the charging current (Ic) measured
should be corrected. Additionally, the user should set the same value for the settings [DIFL-
IcC] at all terminals. When the terminals do not have an identical CT ratio, the user should
set respective values so that the compensations on the primary side are coordinated.
<setting [ DIFL-IDSV ] <
K×I
err
- 58 -
setting[DIFL-I1]
1.5 to 2.0
6F2S1914 (0.49)
(2.5-2)
GRL200 (Soft 033 & 037)