Sel 411L - Figure 9.6 Electrical Operating Time for Circuit Breaker 1 A-Phase

P.9.11
Date Code 20151029 Protection Manual SEL-411L Relay
Monitoring and Metering
Circuit Breaker Monitor
bit to the time the relay detects an open phase condition. Similarly, the relay
measures electrical operating time for closing each phase from the assertion of
BM1CLS to the restoration of phase quantities. The relay compares these
tripping or closing times to the electrical slow operation time thresholds for
tripping and closing, B1ESTRT and B1ESCLT, respectively. The relay issues
an electrical slow operation alarm, B1ESOAL, for 5 seconds when trip or
close times exceed these thresholds. Figure 9.6 shows the timing diagram for
A-phase pole of Circuit Breaker 1.
Figure 9.6 Electrical Operating Time for Circuit Breaker 1 A-Phase
Primary load/fault current can indicate contact closing, contact opening, and
arc extinction, depending upon the actual circuit breaker monitor setup. You
can detect problems within the circuit breaker arcing chamber by timing the
interval from trip/close initiation to electric arc extinction.
EXAMPLE 9.6 Electrical Operating Time Settings
Use Circuit Breaker 1, a single-pole tripping circuit breaker, for this
example. Connect external trip signals to IN201, IN202, and IN203,
and external close signals to IN204, IN205, and IN206 for the A-, B-,
and C-phases, respectively. This example uses control inputs
IN201–IN206; you can use any control inputs that are appropriate for
your installation. The control voltage for this example is 125 Vdc.
Control Inputs IN201–IN206 are located on the relay I/O Interface
board #1. Make the control input settings as explained in Control
Inputs on page P.2.5.
Set the electrical operating time threshold for the slow trip alarm
(B1ESTRT) at 25 ms, and the slow close alarm threshold (B1ESCLT) at
65 ms. Use your company standard practices to determine these
settings for your application. For this example, enter the following
settings.
B1ESTRT := 25 Electrical Slow Trip Alarm Threshold—BK1 (1–999 ms)
B1ESCLT := 65 Electrical Slow Close Alarm Threshold—BK1
(1–999 ms)
EB1MON := Y Breaker 1 Monitoring (Y, N)
BK1TYP := 1 Breaker 1 Trip Type (Single Pole = 1, Three Pole = 3)
BM1TRPA := TPA1 OR IN201 Breaker Monitor A-phase Trip—BK1
(SEL
OGIC Equation)
BM1TRPB := TPB1 OR IN202 Breaker Monitor B-phase Trip—BK1
(SEL
OGIC Equation)
BM1TRPC := TPC1 OR IN203 Breaker Monitor C-phase Trip—BK1
(SEL
OGIC Equation)
BM1CLSA := BK1CL OR IN204 Breaker Monitor A-phase Close—BK1
(SEL
OGIC Equation)
BM1TRPA
(Phase A Close)
A-phase Open
A-phase Open
Electrical Closing Time
BM1CLSA
(Phase A Trip)
Electrical Tripping Time