Basler BE1-951 User Manual

4-64 BE1-951 Protection and Control 9328900990 Rev L
Figure 4-58 shows a logic timing diagram showing all possible sequence control blocks enabled (TRUE).
In
Figure 4-59, 79RTD is the reclose reset time delay and 79#TD is the reclose time delay where # is the
reclose shot number.
79RTD 79RTD 79RTD 79RTD 79RTD
RESET
791TD 792TD 793TD 794TD LOCKOUT RESET
Manual
C
lose
1 2345 1
12345 1
Closed
BREAKER STATUS
Open
RESET
TIMER
79C
SCB
STEP
79SCB
D2635-09
09-10-03
Figure 4-58. S#-79SCB=1/2/3/4/5 Logic Timing Diagram
79RTD 79RTD 79RTD 79RTD 79RTD
RESET
791TD 792TD 793TD 794TD LOCKOUT RESET
Manual
C
lose
1 2345 1
12345 1
Closed
BREAKER STATUS
Open
RESET
TIMER
79C
SCB
STEP
79SCB
D2635-10
11-29-98
Figure 4-59. S#-79SCB=2/3/4/5 Logic Timing Diagram
Zone-Sequence Coordination
To coordinate tripping and reclosing sequences with downstream protective relays and reclosers, the
BE1-951 senses fault current from downstream faults when a user programmable logic, set by the SP-
79ZONE command, picks up and then drops out without a trip output (defined with the SG-TRIGGER
command) occurring. Typically, the low-set instantaneous pickup outputs (50TPPU and 50TNPU) or the
time overcurrent pickup outputs (51PPU and 51NPU) are used for the zone sequence settings (SP-
79ZONE=50TPPU+50TNPU or SP79ZONE=51PPU+51NPU).
If the upstream relay (BE1-951) senses that a downstream device has interrupted fault current, the BE1-
951 will increment the trip/reclose sequence by one operation. This occurs because the BE1-951
recognizes that a non-blocked low set (50TP or 50TN) element picked up and reset before timing out to
trip.
BESTlogic settings are made from the BESTlogic Function Element screen in BESTCOMS.
Figure 4-60
illustrates the BESTCOMS screen used to select Zone Sequence Coordination Logic settings for the
reclosing element. To open the BESTlogic Function Element screen for Reclosing (Zone Sequence
Logic), select Reclosing from the S
creens pull-down menu and click on the Logic button next to Zone
Sequence Logic in the lower right corner of the screen. Alternately, settings may be made using the SP-
79ZONE ASCII command.

Basler BE1-951 Specifications

General

Brand	Basler
Model	BE1-951
Category	Surge Protector
Language	English