Schweitzer Engineering Laboratories SEL-787, Instruction Manual, Page: 194 / 564

5.6
SEL-787 Relay Instruction Manual Date Code 20081022
Metering and Monitoring
Metering
Energy Metering
The SEL-787 with the voltage option includes energy metering. Use this form
of metering to quantify real and reactive energy supplied by the transformer.
Refer to
Figure 5.1 for the definitions of positive real power, negative real
power, positive reactive power, and negative reactive power. Below are the
energy meter values:
➤
MWhP—Positive real 3-phase energy
➤
MWhN—Negative real 3-phase energy
➤
MVARhP—Positive reactive 3-phase energy
➤
MVARhN—Negative reactive 3-phase energy
➤
Last date and time energy meter quantities were reset
Figure 5.5 shows the device response to the METER E command.
=>
MET E <Enter>
SEL-787 Date: 01/23/2008 Time: 13:48:27
TRNSFRMR RELAY Time Source: Internal
Energy
Positive MWH (MWh) 5.3
Negative MWH (MWh) 0.0
Positive MVAR (MVArh) 0.0
Negative MVAR (MVArh) 0.4
LAST RESET = 11/01/2007 10:55:52
=>
Figure 5.5 METER E Command Report
To reset energy meter values, issue the MET RE command as shown in
Figure 5.6 .
=>>
MET RE <Enter>
Reset Metering Quantities (Y,N)?
Y <Enter>
Reset Complete
=>>
Figure 5.6 METER RE Command Report
Maximum and
Minimum Metering
Maximum and minimum metering allows you to determine maximum and
minimum operating quantities such as currents, voltages, power, analog input
quantities, RTD quantities and frequency.
Table 5.5 lists the max/min
metering quantities.
Table 5.5 Maximum/Minimum Meter Values
Relay Option Max/Min Meter Values
Base Model Maximum and minimum line currents IAW1, IBW1, ICW1, IAW2, IBW2, ICW2 (A
primary)
Maximum and minimum IG (residual ground fault current) magnitude (A primary)
With Neutral Current Option (REF) Maximum and minimum neutral current IN magnitudes (A primary)
With Voltage Option VAB, VBC, VCA or VAN, VBN, VCN magnitudes (V primary)
Maximum and minimum real, reactive and apparent 3-phase power (kW, kVAR, kVA)
Maximum and minimum system frequency (Hz)
With RTD option or SEL-2600 series
RTD Module Maximum and minimum RTD temperatures (°C)
With analog input option Maximum and minimum analog input values
(engineering units)