Basler Electric BE1-87B - Manual (Page 17)

SECTION 2
• APPLICATION
TABLE OF CONTENTS
SECTION 2 • APPLICATION .................................................................................................................... 2-1
Application.............................................................................................................................................. 2-1
Application with Lightning Arresters ................................................................................................... 2-1
Application with a Lockout Function ................................................................................................... 2-1
Current Source for High Impedance Differential Relaying ................................................................. 2-1
BE1-87B Flexibility ................................................................................................................................. 2-2
Bus Protection Application ................................................................................................................. 2-2
Shunt Reactor Protection Application ................................................................................................ 2-4
Mixing Two Different Ratio CTs ......................................................................................................... 2-5
General Settings Guidelines .............................................................................................................. 2-5
Operating Principles ............................................................................................................................... 2-5
External Faults ................................................................................................................................... 2-6
Internal Faults ..................................................................................................................................... 2-7
Characteristics ..................................................................................................................................... 2-10
Differential Voltage Pickup ............................................................................................................... 2-10
Differential Pickup Current ............................................................................................................... 2-10
Alarm Voltage Pickup ....................................................................................................................... 2-10
Trip Test Pushbutton ........................................................................................................................ 2-11
CT Test Pushbutton ......................................................................................................................... 2-11
Power LED ....................................................................................................................................... 2-11
Intentional Delay Jumper.................................................................................................................. 2-11
Operating Times ............................................................................................................................... 2-11
Calculation of Settings ......................................................................................................................... 2-12
Calculation of Voltage Differential Settings ...................................................................................... 2-12
Bus Protection .................................................................................................................................. 2-13
Shunt Reactor Protection ................................................................................................................. 2-13
Application with Mixed Multi-Ratio CTs ............................................................................................ 2-13
Current Element Setting ................................................................................................................... 2-14
Minimum Fault to Trip (Voltage Element) ......................................................................................... 2-14
Sample Calculation .............................................................................................................................. 2-15
CT Test Circuit Calculations ................................................................................................................ 2-16
General ............................................................................................................................................. 2-16
Definition of Terms ........................................................................................................................... 2-16
Calculation Steps ............................................................................................................................. 2-17
Example Calculation ......................................................................................................................... 2-17
Figures
Figure 2-1. External AC Connections for Bus Protection .......................................................................... 2-3
Figure 2-2. External DC Connections for Bus Protection .......................................................................... 2-4
Figure 2-3. External AC Connections for Shunt Reactor Protection, Multi-Phase and Line-to-Ground
Faults ......................................................................................................................................................... 2-4
Figure 2-4. External AC Connections for Shunt Reactor Protection, Ground Faults ................................ 2-5
Figure 2-5. Illustration of Single Line-to-Ground Fault at Location F1 ...................................................... 2-7
Figure 2-6. Typical Secondary Excitation for 1200/5 Bushing Current Transformer ................................. 2-8
Figure 2-7. Simplified Internal Connection Diagram for BE1-87B Relay ................................................... 2-9
Figure 2-8. Voltage Appearing Across Full Winding of CT ...................................................................... 2-10
Figure 2-9. Voltage Appearing Across Full Winding of CT ...................................................................... 2-17
Figure 2-10. Voltage Appearing Across Full Winding of CT .................................................................... 2-18
9282300990 Rev P BE1-87B Application i