Schweitzer Engineering Laboratories SEL-751 - Figure 4.124 Adding Two Local Bits

4.202
SEL-751 Relay Instruction Manual Date Code 20170927
Protection and Logic Functions
Front-Panel Settings (SET F Command)
following four settings, using a maximum of 14 valid characters for the
NLBnn setting, and a maximum seven valid characters (0–9, A–Z, -, /, .,
space) for the remainder:
➤ NLBnn: Name the switch (normally the function that the switch
performs, such as SUPERV SW) that appears on the front-
panel display.
➤ CLBnn: Clear local bit. Enter the text that describes the
intended operation of the switch (this text appears on the
display) when LBnn deasserts (OPEN, for example).
➤ SLBnn: Set local bit. Enter the text that describes the intended
operation of the switch (this text appears on the display) when
LBnn asserts (CLOSE, for example).
➤ PLBnn: Pulse local bit. When selecting the pulse operation,
LBnn asserts for only one processing interval before
deasserting again. Enter the text that describes the intended
operation when LBnn asserts (START, for example).
➤ Omit either SLBnn or PLBnn (never CLBnn) by setting the
omitted setting to NA.
For the transformer in our example, configure two local bits: one to replace a
supervisory switch, and the other to start a fan motor. Local bit 1 replaces a
supervisory switch (SUPERV SW) and we use the clear/set combination.
Local bit 2 starts a fan motor (START) that only needs a short pulse to seal
itself in, and we use the clear/pulse combination. Figure 4.124 shows the set-
tings to program the two local bits.
=>>SET F TERSE <Enter>
Front Panel
General Settings
DISPLY PTS ENABL (N,1-32) EDP := 5 ? <Enter>
LOCAL BITS ENABL (N,1-32) ELB := N ? 2 <Enter>
LCD TIMEOUT (OFF,1-30 min) FP_TO := 15 ? > <Enter>
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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 := IN101,"TRFR 1 HV BRKR:",CLOSED,OPEN
? > <Enter>
Local Bits Labels:
LB_ NAME (14 characters; Enter NA to null)
NLB01 :=
? SPERV SW <Enter>
CLEAR LB_ LABEL (7 characters; Enter NA to null)
CLB01 :=
? OPEN <Enter>
SET LB_ LABEL (7 characters; Enter NA to null)
SLB01 :=
? CLOSE <Enter>
PULSE LB_ LABEL (7 characters; Enter NA to null)
PLB01 :=
? NA <Enter>
LB_ NAME (14 characters; Enter NA to null)
NLB02 :=
? FAN START <Enter>
CLEAR LB_ LABEL (7 characters; Enter NA to null)
CLB02 :=
? OFF <Enter>
SET LB_ LABEL (7 characters; Enter NA to null)
SLB02 :=
? NA <Enter>
PULSE LB_ LABEL (7 characters; Enter NA to null)
PLB02 :=
? START <Enter>
Save changes (Y,N)? Y <Enter>
Settings Saved
=>>
Figure 4.124 Adding Two Local Bits