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15.37
Date Code 20171006
Instruction Manual
SEL-400 Series Relays
Communications Interfaces
SEL Distributed Port Switch Protocol (LMD)
Set the RX_ID of the local relay to match the TX_ID of the remote relay. In a
three-terminal case, Relay X transmits to Relay Y, Relay Y transmits to Relay Z,
and Relay Z transmits to Relay X.
lists the M
IRRORED
B
ITS
commu-
nications ID settings for Relays X, Y, and Z.
SEL Distributed Port Switch Protocol (LMD)
MBNUMAN
Number of analog data channels
(hidden and set to 0 if MBNUM := 7 or 8)
0–
n
,
n
= 7–MBNUM
MBANA1
c
Selection for analog Channel 1
Analog quantity label
MBANA2
Selection for analog Channel 2
Analog quantity label
MBANA3
Selection for analog Channel 3
Analog quantity label
MBANA4
Selection for analog Channel 4
Analog quantity label
MBANA5
Selection for analog Channel 5
Analog quantity label
MBANA6
Selection for analog Channel 6
Analog quantity label
MBANA7
Selection for analog Channel 7
Analog quantity label
MBNUMVT
Number of virtual terminal channels
OFF, 0–
n
,
n
= 7–MBNUM–MBNUMAN
a
Must be P for connections to devices that are not SEL-400 series relays.
b
Hidden based on MBNUM setting.
c
Hidden based on MBNUMAN setting.
Table 15.26
M
IRRORED
B
ITS
Communications Message Transmission Period
Speed in Bits
per Second
TXMODE := NORMAL
MBT := N
TXMODE := PACED
MBT := N
MBT :=Y
38400
1.0 ms
3.0 ms
N/A
19200
2.0 ms
3.0 ms
N/A
9600
4.0 ms
4.0 ms
7.0 ms
4800
8.0 ms
8.0 ms
N/A
Table 15.27
M
IRRORED
B
ITS
Communications ID Settings for Three-Terminal
Application
Relay
TX_ID
RX_ID
X
1
3
Y
2
1
Z
3
2
Table 15.25
M
IRRORED
B
ITS
Communications Protocol Settings (Sheet 2 of 2)
Name
Description
Range
Summary of Contents for SEL-421-4
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