Schweitzer Engineering Laboratories SEL-751 - Figure 5.14 MET RA Command Response; Table 5.8 High-Impedance Fault Metering Measured Values; Figure 5.15 MET H (HIF) Command Response

5.13
Date Code 20170927 Instruction Manual SEL-751 Relay
Metering and Monitoring
Metering
High-Impedance Fault
Metering (HIF)
When the SEL-751 is ordered with the Arc Sense technology (AST) option for
high-impedance fault detection, the relay provides high-impedance fault
metering data with the METER HIF (MET H command) report. The MET
HIF command displays the progress of HIF detection alarm and fault in
percent of their preset pickup values (see Table 5.8 for details).
If HIF enable setting EHIF is set to N, the command response is
HIF Not
Enabled
. If setting EHIF is set to Y and any of the initial tuning Relay Word
Bits ITUNE_A, ITUNE_B or ITUNE_C is asserted, the command response is
HIF Algorithm Tuning in Progress. Initial tuning is a 24-hour window.
Figure 5.15 provides an example of MET HIF command report.
=>>MET RA <Enter>
SEL-751 Date: 02/11/2011 Time: 13:42:23
FEEDER RELAY Time Source: External
RA01 1.00
RA02 -32767.00
RA03 -1.00
RA04 0.00
RA05 1000.59
RA06 -1000.61
RA07 2411.01
RA08 2410.99
RA09 98303.00
RA10 -98303.00
RA11 -38400.00
RA12 -65536.00
RA13 0.00
RA14 0.00
RA15 0.00
• •
• •
• •
RA126 0.00
RA127 0.00
RA128 0.00
=>>
Figure 5.14 MET RA Command Response
Table 5.8 High-Impedance Fault Metering Measured Values
Relay Option High-Impedance Fault (HIF) Metering Values
All models with the
AST option
Odd-harmonic alarm and fault values ALG.1 A, ALG.1 B, and
ALG.1 C for Phases A, B and C in percent of preset alarm and
fault thresholds.
Non-harmonic alarm and fault values ALG.2 A, ALG.2 B, and
ALG.2 C for Phases A, B and C in percent of preset alarm and
fault thresholds.
=>>MET HIF <Enter>
Date: 03/31/2011 Time: 14:19:20.655
Time Source: Internal
ALG.1 A ALG.1 B ALG.1 C ALG.2 A ALG.2 B ALG.2 C
Alarm (%) 0.00 0.00 0.00 100.00 0.00 0.00
Fault (%) 0.00 0.00 0.00 0.00 0.00 0.00
=>>
Figure 5.15 MET H (HIF) Command Response
NOTE: The HIF odd-harmonic alarm
and fault output bits are HIA1_A,
HIA1_B, HIA1_C and HIF1_A, HIF1_B,
HIF1_C, respectively. The HIF non-
harmonic alarm and fault output bits
are HIA2_A, HIA2_B, HIA2_C and
HIF2_A, HIF2_B, HIF2_C, respectively.
The Relay Word bits assert when the
corresponding percentage values
reach 100%.