7.17
Date Code 20080918
Instruction Manual
SEL-749M Relay
Communications
SEL ASCII Protocol Details
SEL-749M Date: 12/10/2003 Time: 08:56:03.190
MOTOR RELAY Time Source: external
=>
If no IRIG-B code is present at the serial port input or if the code
cannot be read successfully, the relay responds:
IRIG-B DATA ERROR
=>
If an IRIG-B signal is present, the relay synchronizes its internal clock with
IRIG-B. It is not necessary to issue the
IRI
command to synchronize the relay
clock with IRIG-B. Use the
IRI
command to determine if the relay is properly
reading the IRIG-B signal.
L_D Command (Load Firmware)
Use the
L_D
command to load firmware. See
for information on changes to the firmware and instruction
manual. See
Appendix B: Firmware Upgrade Instructions
for further details
on downloading firmware.
Only download firmware to the front port.
METER Command
The
MET
commands provide access to the relay metering data. The relay
divides the displayed information into two groups:
NOTE:
All ASCII command responses
in this section are examples only. Your
specific relay will have differences
based on model number, firmware
revision number, and application.
➤
Instantaneous
➤
Thermal and RTD
METER k (Instantaneous Metering)
The
MET
k
command displays instantaneous magnitudes (and angles, if
applicable) of the measured and calculated analog quantities.
All angles are displayed between –180 and +180 degrees. For delta-connected
PTs, angles are referenced to VAB or L1. For wye-connected PTs, angles are
referenced to VAN or L1.
If the voltage channels are not supported, or
VAB < 13 V (for delta) or VAN < 13 V (for wye), angles are referenced to L1
current.
To view the instantaneous meter values once, use the
MET
command (see the
example in
). To view the meter values
k
times, use the
MET
k
command, where
k
is a number between 1 and 32767.
Table 7.27
L_D Command (Load Firmware)
Command
Description
Access Level
L_D
Download firmware to the control.
2
Table 7.28
METER k (Instantaneous Metering)
Command
Description
Access Level
MET
k
View/reset relay measured quantities
1
Summary of Contents for SEL-749M
Page 6: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 14: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 20: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 32: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 52: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 118: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 188: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 216: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 224: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 274: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 286: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 306: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 310: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...
Page 314: ...This page intentionally left blank Courtesy of NationalSwitchgear com ...