Date Code 20001006 Inputs, Outputs, Timers, and Other Control Logic 7-39
SEL-351 Instruction Manual
Traditional Indicating Panel Lights
Figure 7.31 shows traditional indicating panel lights wired in parallel with SEL-351 Relay
optoisolated inputs. Input IN1 provides circuit breaker status to the relay, and input IN2
enables/disables reclosing in the relay via the following SELOGIC Control Equation settings:
52A = IN1
79DTL = !IN2 [= NOT(IN2); drive-to-lockout setting]
Figure 7.31: Traditional Panel Light Installations (Model 0351xT Example)
Note that Figure 7.31 corresponds to Figure 7.4 (factory input settings example).
Reclosing Relay Status Indication
In Figure 7.31, the 79 ENABLED panel light illuminates when the “79 Enable” switch is closed.
When the “79 Enable” switch is open, the 79 ENABLED panel light extinguishes, and it is
understood that the reclosing relay is disabled.
Circuit Breaker Status Indication
In Figure 7.31, the BREAKER CLOSED panel light illuminates when the 52a circuit breaker
auxiliary contact is closed. When the 52a circuit breaker auxiliary contact is open, the BREAKER
CLOSED panel light extinguishes, and it is understood that the breaker is open.
Traditional Indicating Panel Lights Replaced with Rotating Default Display
The indicating panel lights are not needed if the rotating default display feature in the SEL-351
Relay is used. Figure 7.32 shows the elimination of the indicating panel lights by using the
rotating default display.
Courtesy of NationalSwitchgear.com
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