Advertisement
Dead line detection
2.24.3
The dead line detection (DLD) determinates whether the line is out-of-service or energized.
Checking for the voltage existence in three-phase is required if all CBs are closed.
Under-voltage relay
(i)
Two relay elements are provide in the UV: a phase-to-phase (UVLS) and a phase-to-ground
(UVLG). Both elements operate when On is set for the [DLDbyUV].
Decision of CB operation
(ii)
Deciding the dead line state is carried out by examining the CB position. The user should set
On for the scheme switch [DLDbyCB] for the decision.
Detection time
(iii)
The examination period is required in the DLD detection. The period is set using the setting
[TDSSV]. The user can set the detection time among 0 to 100
Dead line detection logic
(iv)
Figure 2.24-3 shows the detection of an under voltage condition. The logic can determine
whether the line is dead or energized.
A
UVLG
B
C
AB
UVLS
BC
CA
DLDbyUV
From
DLDbyCB
CB decision logic
CB_ALLPH_OPEN
Figure 2.24-3 Dead line detection logic with under voltage relays
8000001B60
8100001B61
8200001B62
≥1
&
8400001B63
8500001B64
8600001B65
≥1
&
On
On
&
- 274 -
seconds.)
TDLD
&
t
0
&
t
0
0.00 to 3000.00s
6F2T0207 (0.01)
To Common of DEFCAR
UVLG-A
UVLG-B
UVLG-C
UVLG-AB
UVLG-BC
UVLG-CA
DEAD_LINE_DETECT
To SOTF-OC
8000001B9C
≥1
DEAD_LINE_DETECT
UVLG-OR
UVLG-AND
UVLS-OR
UVLS-AND
GRE200 (5,6)
Advertisement
