Toshiba GR 200 Series, Instruction Manual

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6F2S1915 (0.46)
GRZ200 (Soft 031 & 032)
- 322 -
as having lumped constants; Equation (2.23-8) is sufficient to compute the fault distance (
GF =
χ
) for faults that occur within 100km (62 mile) of the length of the transmission line. When the
fault distance is greater than 100km (62 mile), Equation (2.23-4) is used to obtain a
compensated value for the fault distance (
GF = χ"
). (2.66.1.2)
2.23.2
Output of FL computation on display
Although the display screens and operations in the standard IED are discussed separately in
the Chapter
Recording function
, the display screen for the FL function is described here
because the FL output is unique compared to that of the standard display screens. Figure
2.23-2 shows an example of the FL display screen.
Figure 2.23-2 FL information in km and percent (%) on the screen
Note: If there is an error in the setting information with regard to the length of the
transmission line, the FL computation does not start (a dash sign “—” is displayed
on the screen).
(i)
Fault distance expressed in kilometers or miles
The fault distance can be displayed in the user-preferred unit† (see Figure 2.23-2.a).
Additionally, the FL computation does not output the fault distance
until a trigger signal‡ has
been removed for the FL function.
†Note: The user should note that the fault distance is based on the location of the local
IED (see Figure 2.23-1). Figure 2.23-2 is shown in kilometers, but the user can
change that so that the fault distance is expressed in miles. The setting is
discussed later. (See section 2.23.3(iv))
‡Note: We shall discuss the trigger signal in the succeeding section.
(ii)
Fault distance in percentage
The user can view the fault distance as a percentage value (see Figure 2.23-2.b).
a. Fault distance in kilometers
FL
****
.
*
km
***
% OB / NC
c. Fault information
b. Fault distance in percent