Sel 751A, Instruction Manual

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7.23
Date Code 20100129 Instruction Manual SEL-751A Relay
Communications
SEL ASCII Protocol and Commands
➤
Parity error
➤
Overrun
➤
Re-sync
➤
Data error
➤
Loopback
➤
Underrun
CONTROL Command (Control Remote Bit)
Use the CON command (see Table 7.10 ) to control remote bits (Relay Word
bits RB01–RB32). You can use the CON function from the front panel
(
Control > Outputs
) to pulse the outputs. Remote bits are device variables
that you set via serial port communication only; you cannot navigate Remote
Bits via the front-panel HMI. You can select the control operation from three
states: set, clear, or pulse, as described in
Table 7.11 .
Table 7.9 COM Command
Command Description Access Level
COM S A or
COM S B
Return a summary report of the last 255 records in
the communications buffer for either M
IRRORED
B
ITS
communications Channel A or Channel B
when only one channel is enabled.
1
COM A Return a summary report of the last 255 records in
the communications buffer for M
IRRORED
B
ITS
communications Channel A.
1
COM B Return a summary report of the last 255 records in
the communications buffer for M
IRRORED
B
ITS
communications Channel B.
1
COM L A Appends a long report to the summary report of the
last 255 records in the communications buffer for
M
IRRORED
B
ITS
communications Channel A.
1
COM L B Appends a long report to the summary report of the
last 255 records in the communications buffer for
M
IRRORED
B
ITS
communications Channel B.
1
COM C Clears all communications records. If both M
IR
-
RORED
B
ITS
channels are enabled, omitting the
channel specifier (A or B) clears both channels.
1
COM C A Clears all communications records for Channel A. 1
COM C B Clears all communications records for Channel B. 1
Table 7.10 CONTROL Command
Command Description Access Level
CON RB nn
a
k
b
a
Parameter nn is a number from 01 to 32, representing RB01 through RB32.
b
Parameter k is S, C, or P.
Set a Remote Bit to set, clear, or pulse. 2
Table 7.11 Three Remote Bit States
Subcommand Description Access Level
S Set Remote bit (ON position) 2
C Clear Remote bit (OFF position) 2
P Pulse Remote bit for 1/4 cycle (MOMENTARY
position) 2