Sel SEL-787 - Page 385

10.13
Date Code 20150130 Instruction Manual SEL-787 Relay
Testing and Troubleshooting
Self-Test
VT Board A/D Offset Warn
Measure dc offset at each input channel
–50 mV
to
+50 mV
No Not
Latched
No NA STA C, to clear
the warning in the
status report.
Contact SEL if
failure returns.
+0.9 V Fail
Monitor +0.9 V power supply
0.855 to
0.945 V
Yes Latched Yes Status Fail
+0.9 V Failure
+1.2 V Fail
Monitor +1.2 V power supply
1.152 to
1.248 V
Yes Latched Yes Status Fail
+1.2 V Failure
+1.5 V Fail
Monitor +1.5 V power supply
1.35 to
1.65 V
Yes Latched Yes Status Fail
+1.5 V Failure
+1.8 V Fail
Monitor +1.8 V power supply
1.71 to
1.89 V
Yes Latched Yes Status Fail
+1.8 V Failure
+3.3 V Fail
Monitor +3.3 V power supply
3.07 to
3.53 V
Yes Latched Yes Status Fail
+3.3 V Failure
+5 V Fail
Monitor +5 V power supply
4.65 to
5.35 V
Yes Latched Yes Status Fail
+5 V Failure
+2.5 V Fail
Monitor +2.5 V power supply
2.32 to
2.68 V
Yes Latched Yes Status Fail
+2.5 V Failure
+3.75 V Fail
Monitor +3.75 V power supply
3.48 to
4.02 V
Yes Latched Yes Status Fail
+3.75 V Failure
–1.25 V Fail
Monitor -1.25 V power supply
–1.16 to
–1.34 V
Yes Latched Yes Status Fail
–1.25 V Failure
–5 V Fail
Monitor -5 V power supply
–4.65 to
–5.35 V
Yes Latched Yes Status Fail
–5 V Failure
Clock Battery
Monitor Clock Battery
2.3 to
3.5 V
No Not
Latched
Yes NA STA C, to clear
the warning in the
status report.
Contact SEL if
failure returns.
Clock Chip
Unable to communicate with clock or
fails time keeping test
No Not
Latched
Yes NA STA C, to clear
the warning in the
status report.
Contact SEL if
failure returns.
Clock Chip RAM
Clock chip static RAM fails
No Not
Latched
Yes NA STA C, to clear
the warning in the
status report.
Contact SEL if
failure returns.
External RTD
Fail if no comm, or the external RTD
module reports open RTDs, shorted
RTDs, a power supply failure
NA NA No RTD Failure
Table 1 0.8 Rel ay Self-Test s (Sheet 3 of 4)
Self-Test Description
Normal
Range
Protection
Disabled
on Failure
Alarm
Status
Auto
Message
on Failure
Front Panel
Message
on Failure
Corrective
Action