Schweitzer Engineering Laboratories SEL-701 - Page 118

701 Motor Protection Relay Date Code 20010719
Settings Calculation
Sequential Events Recorder (SER) Settings
4.54
Table 4.42 Default SER Trigger Setting
Relay Word Bits Definitions (Continued)
Relay Word Bits Relay Word Bit Definitions
50G1T, 50G2T,
50N1T, 50N2T
Ground Fault.
Assert when the relay issues a ground fault trip
due to pickup and timeout of a residual (50G1T or 50G2T, sum of
phase current inputs) or neutral (50N1T or 50N2T, IN current
input) definite-time overcurrent element.
RTDFLT
RTD Fault.
Asserts when any enabled RTD is short- or open-
circuited, connected with reversed polarity, or if communication
with the external RTD module is interrupted. This Relay Word bit
is inactive if RTD monitoring is disabled.
WDGALRM,
WDGTRIP
Winding RTD Temperature Alarm or Trip.
WDGALRM
asserts when any healthy motor winding RTD temperature exceeds
its settable alarm threshold. WDGTRIP asserts when any one or
two healthy motor winding RTD temperatures exceed their
settable trip thresholds. Both Relay Word bits are inactive if RTD
monitoring is disabled or if no winding RTDs are connected.
BRGALRM,
BRGTRIP
Bearing RTD Temperature Alarm or Trip.
BRGALRM asserts
when any healthy motor bearing RTD temperature exceeds its
settable alarm threshold. BRGTRIP asserts when any one or two
healthy motor bearing RTD temperatures exceed their settable trip
thresholds. Both Relay Word bits are inactive if RTD monitoring
is disabled or if no bearing RTDs are connected.
AMBALRM,
AMBTRIP
Ambient RTD Temperature Alarm or Trip.
AMBALRM
asserts when the healthy ambient RTD temperature exceeds its
settable alarm threshold. AMBTRIP asserts when the healthy
ambient RTD temperature exceeds its settable trip threshold. Both
Relay Word bits are inactive if RTD monitoring is disabled or if
no ambient temperature RTD is connected.
OTHALRM,
OTHTRIP
Other RTD Temperature Alarm or Trip.
OTHALRM asserts
when any healthy “Other” RTD temperature exceeds its settable
alarm threshold. OTHTRIP asserts when any one or two healthy
“Other” RTD temperatures exceed their settable trip thresholds.
Both Relay Word bits are inactive if RTD monitoring is disabled
or if no “Other” RTDs are connected.
81D1T, 81D2T,
81D3T
Level 1, Level 2, and Level 3 Time-Delayed
Over-/Underfrequency.
81DnT asserts when an over- or
underfrequency (depending on the pickup setting) has been
detected for the duration of the time-delay setting. All three Relay
Word bits are inactive if the relay is not equipped with optional
voltage inputs.
(Continued)