Distance Relay Setting Examples
GARD 8000 Distance Relay
RFL Electronics Inc.
Description Range
Units
Step
Actual
Open Brkr Carrier sending
Enables open breaker carrier send. Used with Permissive schemes
(PUTT, POTT, DCUB, DTT).
No - Yes
-
1
No
Security Time
Sets a pick-up delay for a carrier receive signal for DTT schemes
and weak feed logic. This will ensure that no spurious carrier signal
will cause a false trip at the receiving end.
0 - 50
ms
1
0
Weak infeed Undervoltage Level
Sets the undervoltage threshold for Weak Infeed tripping.
15 - 70
V
0.01
45
LOP Block Weak Infeed
Enables block of weak infeed tripping by loss-of-potential block.
No - Yes
-
1
No
Distance Pilot Scheme
Selects the type of scheme used.
Step
Distance
Zone 1
Extension
PUTT
DTT
POTT
DCUB
DCB - 1
DCB
Dist Carrier Time
Sets the drop-out delay for carrier send. Used with Permissive
schemes (PUTT, POTT, DCUB, DTT).
0 - 200
ms
10
50
Dist Coord Time
Sets a coordination drop-out time delay for the carrier start signal
from the reverse blocking zone, providing transient block function.
0 - 50
ms
1
20
DCB dist delay time
Sets the time delay for Directional Comparison Blocking (DCB) trip
signal. This is the amount of time the forward pilot zone will wait to
receive a blocking carrier signal before trip is released.
0 - 200
ms
10
10
Z1 Ext. Block Time
This is the time following breaker closing for when Zone 1
extension will become active. This prevents trip from an
overreaching zone following reclosing. Used for Zone 1 Extension
scheme.
0.05 - 300
s
0.01
10
Overreaching Zone
Determines which zone is used as overreaching Pilot zone (Z2 or
Z3).
Zone 2
Zone 3
-
1
Zone 2
Distance Weak Infeed Logic Output
Set whether to use weak infeed echo (echo), week infeed trip and
echo (ECHO+TRIP) or no weak infeed logic (None)
None
Echo
ECHO+T
RIP
- 1
None
Enable Dist. Curr. Rev. trans. Blocking
Enable Transient Block Logic for the overreaching permissive pilot
schemes (POTT, DCUB)
No - Yes
-
1
No
Carrier Fast Sending
This setting is applicable to Directional Comparison Blocking
(DCB) only and enables to select Carrier Start from non-directional
phase and ground overcurrent elements, in addition to the reverse
blocking zone. The 50P-1, 50G-1 elements are utilized for this
function.
No - Yes
-
1
No
August 1, 2009
8-30
973.334.3100
