Schweitzer Engineering Laboratories SEL-587Z - Table 4.7 Processing Order of Relay Elements and Logic (Top to Bottom)

4.13
Date Code 20020903 SEL-587Z Instruction Manual
Control Logic
SEL
OGIC Control Equations
Processing Order and Processing Interval
The relay elements and logic (and corresponding SELOGIC control equation
settings and resultant Relay Word bits) are processed in the order shown in
Tab le 4. 7 (top to bottom). The relay processing interval is every 1/8-cycle, and
the Relay Word bit states (logical 1 or logical 0) are updated with each
1/8-cycle pass. Once a Relay Word bit is updated during a 1/8-cycle pass, it
retains the state (logical 1 or logical 0) until updated again on the next
1/8-cycle pass.
Table 4.7 Processing Order of Relay Elements and Logic (top to bottom)
Relay Elements and Logic
(corresponding SEL
OGIC control
equations listed in parentheses)
Relay Word Bits
Local Control Switches LB1–LB8
Remote Control Switches RB1–RB8
Optoisolated Inputs IN1, IN2
Demand Ammetering PDEM, GDEM, QDEM
Differential Elements 87A1, 87A2, 87B1, 87B2, 87C1, 87C2
Instantaneous Overcurrent Elements 50P1–50P3, 50A1, 50B1, 50C1, 50A2,
50B2, 50C2, 50G1, 50G2, 50Q1, 50Q2
Time-Overcurrent Elements
51PTC, 51ATC, 51BTC,
51CTC, 51GTC, 51QTC
51P, 51PT, 51PR, 51A, 51AT, 51AR,
51B, 51BT, 51BR, 51C, 51CT, 51CR,
51G, 51GT, 51GR, 51Q, 51QT, 51QR
Trip Logic (TR1, 2, 3; ULTR1, 2 , 3) TRIP1, TRIP2, TRIP3
Close Logic (52A, CL, ULCL) CLOSE, CF
SEL
OGIC Control Equation
Variables/Timers (SV1–SV14)
SV1–SV14, SV5T–SV14T
Output Contacts (OUT1–OUT4) OUT1–OUT4
Display Points (DP1–DP8)
Event Report Triggers (ER1, ER2)