P.11.38
SEL-411L Relay Protection Manual Date Code 20151029
Testing and Troubleshooting
Relay Self-Tests
Relay Self-Tests
The relay continuously runs many self-tests to detect out-of-tolerance
conditions. These tests run at the same time as relay protection and
automation logic, but do not degrade relay performance.
The relay provides a number of alarms to indicate different conditions, as
shown in Table 11.11.
Status Warning and
Status Failure
The relay reports out-of-tolerance conditions as a status warning or a status
failure. For conditions that do not compromise relay protection, yet are
beyond expected limits, the relay issues a status warning and continues to
operate. A severe out-of-tolerance condition causes the relay to declare a
status failure and enter a protection-disabled state. During a protection-
disabled state, the relay suspends protection element processing and trip/close
logic processing and de-energizes all control outputs. When disabled, the
ENABLED front-panel LED is not illuminated.
The relay signals a status warning by pulsing the HALARMP, HALARMA,
and HALARM Relay Word bits (hardware alarm) to logical 1 for five seconds.
For a status failure, the relay latches the HALARML and HALARM Relay
Word bits at logical 1. Some hardware failures prevent the relay from
operating. In such cases, Relay Word bits HALARML and HALARM do not
assert.
Once HALARMP pulses, Relay Word bit HALARMA continues to assert for
approximately five seconds once per minute to indicate that a hardware
warning has occurred. HALARMA continues to pulse until it is reset by
pulsing SEL
OGIC control equation RST_HAL. Restarting the relay also resets
HALARMA. HALARMP does not assert again for the same alarm condition,
unless the condition is cleared and returns.
The SEL-411L will restart on certain diagnostic failures. When this occurs,
the relay will log a
Diagnostic Restart in the SER. See Appendix A:
Firmware and Manual Versions for affected firmware revisions. To provide
remote status indication, connect the b contact of OUT208 to your control
Table 11.11 Alarm Relay Word Bits
Alarm Relay Word Bit Description
HALARML Latches for any relay failures.
HALARMP Pulses for five seconds when a warning condition occurs.
HALARMA Starts pulsing for five seconds every minute whenever a new
warning condition occurs and continues to pulse until the
RST_HAL logic reset is asserted.
RST_HAL Resets the HALARMA operation (similar to the other logic
resets in the relay).
HALARM Equivalent to HALARML OR HALARMP
SETCHG Pulses for one second whenever settings are changed.
GRPSW Pulses for one second whenever groups are switched.
ACCESS This bit is set when a user is logged in at access Level B or
higher
BADPASS Pulses for one second whenever a user enters three successive
bad passwords
SALARM BADPASS OR SETCHG OR GRPSW
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