Sel SEL-351S - Page 484

10.20
SEL-351S Relay Instruction Manual Date Code 20080103
Serial Port Communications and Commands
Command Explanations
If the relay successfully synchronizes to IRIG, it sends the following header
and access level prompt:
FEEDER 1 Date: 03/05/97 Time: 10:15:09.609
STATION A
=>
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.
LDP Command (Load Profile Report—Available in Firmware Versions
6and7)
Use the LDP command to view the Load Profile report. For more information
on Load Profile reports, see Section 8: Breaker Monitor, Metering,
and Load Profile Functions.
MET Command (Metering Data)
The MET commands provide access to the relay metering data. Metered
quantities include phase voltages and currents, sequence component voltages
and currents, power, frequency, substation battery voltage, energy, demand,
and maximum/minimum logging of selected quantities. To make the extensive
amount of meter information manageable, the relay divides the displayed
information into five groups: Instantaneous, Demand, Energy, Maximum/
Minimum, and Synchrophasors.
MET k—Instantaneous Metering
The MET k command displays instantaneous magnitudes (and angles if
applicable) of the following quantities:
NOTE: If the serial port AUTO setting
is DTA, the SEL-351S response for MET,
MET X, and MET D will be formatted
differently on that serial port than
shown below.
Currents I
A,B,C,N
Input currents (A primary)
I
G
Residual ground current (A primary;
I
G
=3I
0
= I
A
+ I
B
+ I
C
)
Voltages V
A,B,C,S
Wye-connected voltage inputs
(kV primary)
V
AB,BC,CA,S
Delta-connected voltage inputs
(kV primary)
Power MW
A,B,C
Single-phase megawatts
(wye-connected voltage inputs only)
MW
3P
Three-phase megawatts
MVAR
A,B,C
Single-phase megavars
(wye-connected voltage inputs only)
MVAR
3P
Three-phase megavars