Schweitzer Engineering Laboratories SEL-351 - Section 8: Breaker Monitor, Metering, and Load Profile Functions;Section 8: Breaker Monitor, Metering, and Load Profile Functions

Date Code 20001006 Breaker Monitor, Metering, and Load Profile Functions i
SEL-351 Instruction Manual
TABLE OF CONTENTS
SECTION 8: BREAKER MONITOR, METERING, AND LOAD
PROFILE FUNCTIONS.............................................................................. 8-1
Introduction..............................................................................................................................8-1
Breaker Monitor.......................................................................................................................8-1
Breaker Monitor Setting Example......................................................................................8-4
Breaker Maintenance Curve Details...........................................................................8-4
Operation of SELOGIC
®
Control Equation Breaker Monitor Initiation Setting
BKMON............................................................................................................8-6
Breaker Monitor Operation Example.................................................................................8-7
0% to 10% Breaker Wear..........................................................................................8-7
10% to 25% Breaker Wear ........................................................................................8-7
25% to 50% Breaker Wear ........................................................................................8-7
50% to 100% Breaker Wear ......................................................................................8-7
Breaker Monitor Output..................................................................................................8-12
Example Applications..............................................................................................8-12
View or Reset Breaker Monitor Information ....................................................................8-12
Via Serial Port.........................................................................................................8-12
Via Front Panel .......................................................................................................8-13
Determination of Relay Initiated Trips and Externally Initiated Trips ...............................8-13
Factory Default Setting Example .............................................................................8-13
Additional Example.................................................................................................8-13
Station DC Battery Monitor....................................................................................................8-14
DC Under- and Overvoltage Elements .............................................................................8-15
Create Desired Logic for DC Under- and Overvoltage Alarming ......................................8-15
DCLO < DCHI (Top of Figure 8.10).......................................................................8-16
DCLO > DCHI (Bottom of Figure 8.10)..................................................................8-17
Output Contact Type Considerations (“a” or “b”) ....................................................8-17
Additional Application ....................................................................................................8-17
View Station DC Battery Voltage....................................................................................8-18
Via Serial Port.........................................................................................................8-18
Via Front Panel .......................................................................................................8-18
Analyze Station DC Battery Voltage ...............................................................................8-18
Station DC Battery Voltage Dips During Circuit Breaker Tripping...........................8-18
Station DC Battery Voltage Dips During Circuit Breaker Closing ............................8-19
Station DC Battery Voltage Dips Anytime ...............................................................8-19
Operation of Station DC Battery Monitor When AC Voltage is Powering the Relay .........8-19
Demand Metering...................................................................................................................8-20
Comparison of Thermal and Rolling Demand Meters.......................................................8-20
Thermal Demand Meter Response (EDEM = THM).................................................8-22
Rolling Demand Meter Response (EDEM = ROL)...................................................8-22
Time = 0 Minutes.............................................................................................8-23
Time = 5 Minutes.............................................................................................8-23
Time = 10 Minutes...........................................................................................8-24
Time = 15 Minutes...........................................................................................8-24
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