Schweitzer Engineering Laboratories SEL-701 - Appendix B: SEL OGIC Control Equations & Relay Logic; Introduction

Date Code 20010719 701 Motor Protection Relay
APPENDIX B
SELOGIC
®
Control Equations &
Relay Logic
Introduction
The SEL-701 Relay is equipped with programmable logic so you can customize
various relay functions. Use the programmable logic components described in this
appendix to modify the factory default logic settings discussed in Section 4: Settings
Calculation. This appendix also describes SEL
OGIC
®
control equations and their
various applications within the SEL-701 Relay. Specific topics include:
 General Operation of the Relay.
 Relay Word Bits.
 SEL
OGIC Control Equations.
 Front-Panel Display Configuration Settings.
 Nondedicated SEL
OGIC Control Equation Variables.
 Latching Variables.
 Stop/Trip Logic.
 Breaker Auxiliary Contact Input.
 Start and Emergency Restart Logic.
 ACCESS2 Input Logic.
 TARR Input Logic.
 Speed Switch Contact Input.
 Event Triggering.
 Output Contact Control.
 Remote Control Functions.
Table B.1 on page B.4 and Table B.2 on page B.5 summarize all the Relay Word
bits. Use the Relay Word bits to create SEL
OGIC control equation settings. Figures in
this section summarize the operation of many protection elements.