Sel 411L - Page 653

P.9.7
Date Code 20151029 Protection Manual SEL-411L Relay
Monitoring and Metering
Circuit Breaker Monitor
and advances the trip counter by one count. There are separate current
accumulators and trip counters for each circuit breaker pole. Table 9.4 shows
the factory default settings for circuit breaker monitor initiation.
NOTE: Factory defaults differ for
single-pole tripping and three-pole
tripping. Three-pole tripping uses the
single setting BM1TRPA for all three
poles.
Initiation settings can include both internal and external tripping conditions. In
order to capture trip information initiated by devices other than the relay, you
must program the SEL
OGIC control equation BM1TRP to sense these trips.
EXAMPLE 9.3 Circuit Breaker Monitor External Trip Initiation
Connect external trip signals to the relay control inputs. This example
uses input IN201; you can use any control inputs that are appropriate
for your installation. Control Input IN201 is located on the relay I/O
Interface Board #1, optoisolated input.
If you want Circuit Breaker Monitor 1 to initiate for the trip elements
TPA1, TPB1, and TPC1, or for external trips, set these SEL
OGIC control
equations from the SET M ASCII command or the
ACSELERATOR
QuickSet
Breaker Monitor Settings tree view:
BK1TYP := 1 Breaker 1 Trip Type (Single Pole = 1, Three Pole = 3)
BM1TRPA := TPA1 OR IN201 Breaker Monitor A-phase Trip
Initiate—BK1
BM1TRPB := TPB1 OR IN202 Breaker Monitor B-phase Trip
Initiate—BK1
BM1TRPC := TPC1 OR IN203 Breaker Monitor C-phase Trip
Initiate—BK1
EXAMPLE 9.4 Using a Control Input to Capture External and
Internal Trip Commands
You can also capture all trip information for circuit breaker trips by
using a relay control input to monitor the trip bus for the given circuit
breaker. Figure 9.4 shows an illustration of this method in which
IN206 connects to the Circuit Breaker 1 A-phase trip bus (via a parallel
connection across the trip bus), and asserts for any trip from any
source. This example uses inputs IN206; you can use any control
inputs that are appropriate for your installation. Vdc for this example
is 125 Vdc.
Table 9.4 Circuit Breaker Monitor Initiate SEL
OGIC Control Equations
Name Description Default Comment
a
a
See Table 9.1.
BM1TRPA BK1 monitor initiate equation 3PT If BK1TYP := 3
BM1TRPA A-phase BK1 monitor initiate equation TPA1 If BK1TYP := 1
BM1TRPB B-phase BK1 monitor initiate equation BM1TRPA If BK1TYP := 1
BM1TRPC C-phase BK1 monitor initiate equation BM1TRPA If BK1TYP := 1