13.1.5 Settings
PID-3766-SETTINGS v7
Table 226: ZCPSCH Group settings (basic)
Name
Values (Range) Unit Step Default Description
Operation Off
On
- - Off Operation Off / On
SchemeType Intertrip
Permissive UR
Permissive OR
Blocking
DeltaBlocking
-
- Permissive UR Scheme type
tCoord 0.000 - 60.000 s 0.001 0.035 Co-ordination time for blocking
communication scheme
tSendMin 0.000 - 60.000 s 0.001 0.100 Minimum duration of a carrier send
signal
Table 227: ZCPSCH Group settings (advanced)
Name Values (Range) Unit Step Default Description
Unblock Off
NoRestart
Restart
-
- Off Operation mode of unblocking logic
DeltaI 0 - 200 %IB 1 10 Current change level in % of IBase for
fault inception detection
DeltaU 0 - 100 %UB 1 5 Voltage change level in % of UB for fault
inception detection
Delta3I0 0 - 200 %IB 1 10 Zero seq current change level in % of
IBase
Delta3U0 0 - 100 %UB 1 5 Zero seq voltage change level in % of
UBase
tSecurity 0.000 - 60.000 s 0.001 0.035 Security timer for loss of carrier guard
detection
Table 228: ZCPSCH Non group settings (advanced)
Name
Values (Range) Unit Step Default Description
GlobalBaseSelector 1 - 12 - 1 1 Selection of one of the Global Base
Value groups
13.1.6 Operation principle
M13893-3 v5
Depending on whether a reverse or forward directed impedance zone is used to
issue the send signal, the communication schemes are divided into blocking and
permissive schemes, respectively.
A permissive scheme is inherently faster and has better security against false
tripping than a blocking scheme. On the other hand, a permissive scheme depends
1MRK 505 394-UEN A Section 13
Scheme communication
Line differential protection RED650 2.2 IEC 403
Technical manual