Schweitzer Engineering Laboratories SEL-387E - SECTION 4: CONTROL LOGIC

Date Code 20080110 Control Logic i
SEL-387E Instruction Manual
TABLE OF CONTENTS
SECTION 4: CONTROL LOGIC ............................................................4-1
Optoisolated Inputs.......................................................................................................................4-1
Input Functions .....................................................................................................................4-1
Factory Settings Examples....................................................................................................4-2
Local Control Switches.................................................................................................................4-2
Remote Control Switches .............................................................................................................4-2
Remote Bit Application ........................................................................................................4-3
Remote Bit States Not Retained When Power Is Lost .........................................................4-3
Remote Bit States Retained When Settings Changed or Active Setting Group
Changed.........................................................................................................................
4-3
Multiple Setting Groups ...............................................................................................................4-3
Active Setting Group Indication ...........................................................................................4-3
Selecting the Active Setting Group ......................................................................................4-4
Operation of SEL OGIC Control Equation Settings SS1 through SS6 ...................................4-4
Operation of Serial Port GROUP Command and Front-Panel GROUP Pushbutton............4-5
Relay Disabled Momentarily During Active Setting Group Change ...................................4-5
Active Setting Group Switching Example............................................................................4-5
CHSG Relay Word Bit Asserts During Setting Group Changes ..........................................4-7
Active Setting Group Retained for Power Loss, Settings Change .......................................4-7
Note: Make Active Setting Group Switching Settings With Care..........................4-8
SEL OGIC Control Equation Sets (1 through 3) Variables ............................................................4-8
Variables/Timers...................................................................................................................4-9
Timers Reset When Power Is Lost, Settings Are Changed, or Active Setting
Group Is Changed..................................................................................................
4-9
Latch Control Switches.........................................................................................................4-9
Latch Bit Behavior for Power Loss, Settings Change, Active Group Change ...........4-11
Note: Make Latch Bit Settings With Care .........................................................4-11
Output Contacts ..........................................................................................................................4-11
Factory Settings Example ...................................................................................................4-11
Operation of Output Contacts for Different Output Contact Types ...................................4-12
Output Contacts OUT101 through OUT107...............................................................4-12
ALARM Output Contact.............................................................................................4-12
Rotating Default Display ............................................................................................................4-13
LED Targeting Logic..................................................................................................................4-13
LED 1 – EN – Relay Enabled .............................................................................................4-14
LED 2 – TRIP – Relay Trip................................................................................................4-14
LED 3 – INST – Instantaneous Trip...................................................................................4-14
LED 4 – 87-1 – Differential Element 1 ..............................................................................4-14
LED 5 – 87-2 – Differential Element 2 ..............................................................................4-15
LED 6 – 87-3 – Differential Element 3 ..............................................................................4-15
LED 7 – 81 – Over-/Underfrequency Element Trip...........................................................4-15
LED 8 – 24 – Volts-per-Hertz Element ..............................................................................4-15
LED 9 – A – A-Phase Involved in the Fault (Programmable LEDA)................................4-15
LED 10 – B – B-Phase Involved in the Fault (Programmable LEDB)...............................4-16