Sel 751A, Instruction Manual

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4.114
SEL-751A Relay Instruction Manual Date Code 20100129
Protection and Logic Functions
Front-Panel Settings (SET F Command)
Name, Alias, Set String, and Clear String
When all four strings have entries, the relay reports all states.
Figure 4.62 shows the settings for the example, using the SET F command.
Use the > character to move to the next settings category.
=>>
SET F TERSE <Enter>
Front Panel
General Settings
DISPLY PTS ENABL (N,1-32) EDP := 4 ? > <Enter>
•
•
•
Target LED Set
TRIP LATCH T_LED (Y,N) T01LEDL := Y ? > <Enter>
Display Point Settings (maximum 60 characters):
(Boolean): Relay Word Bit Name, "Alias", "Set String", "Clear String"
(Analog) : Analog Quantity Name, "User Text and Formatting"
DISPLAY POINT DP01 (60 characters)
DP01 := RID,"{16}"
? IN101,"TRFR 1 HV BRKR:",CLOSED,OPEN <Enter>
DISPLAY POINT DP02 (60 characters)
DP02 := TID,"{16}"
? IN102,"TRFR 1 LV BRKR:",CLOSED,OPEN <Enter>
DISPLAY POINT DP03 (60 characters)
DP03 := IAV, "IAV CURR {5} A"
? END <Enter>
Save changes (Y,N)? Y <Enter>
Settings Saved
=>>
Figure 4.62 Display Point Settings
Figure 4.63 shows the display when both HV and LV breakers are open (both
IN101 and IN102 deasserted). Figure 4.64 shows the display when the HV
breaker is closed, and the LV breaker is open (IN101 asserted, but IN102 still
deasserted).
Figure 4.63 Front-Panel Display—Both HV and LV Breakers Open
Figure 4.64 Front-Panel Display—HV Breaker Closed, LV Breaker Open
Name String, Alias String, and Either Set String or Clear String Only
The following discusses omission of the Clear String; omission of the Set
String gives similar results. Omitting the Clear String causes the relay to only
show display points in the set state, using the
SET F command as follows:
DP01 := RID, “{16}”
? IN101,"TRFR 1 HV BRKR:",CLOSED <Enter>
When the Relay Word bit IN101 deasserts, the relay removes the complete
line with the omitted Clear String (TRFR 1 HV BRKR). When both breakers
are closed, the relay has the set state information for both HV and LV
breakers, and the relay displays the information as shown in
Figure 4.65 .
Table 4.61 Entries for the Four Strings
Name Alias Set String Clear String
IN101 TRFR 1 HV BRKR OPEN CLOSED
TRFR 1 HV BRKR:= OPEN
TRFR 1 LV BRKR:= OPEN
TRFR 1 HV BRKR:= CLOSED
TRFR 1 LV BRKR:= OPEN