Sel 411L - Table 3.114 SOTF Settings; Table 3.115 SOTF Relay Word Bits

P.3.218
SEL-411L Relay Protection Manual Date Code 20151029
Protection Functions
Switch-Onto-Fault Logic
SOTF Options
Set EVRST = Y to enable the Voltage Reset logic. If the system voltage is
balanced (ratio of negative-sequence voltage to positive-sequence voltage is
below 0.1), Relay Word bit SOTFE resets when the relay measures positive-
sequence voltage at greater than VRSTPU times nominal voltage.
If setting ESPSTF (single-pole SOTF enable) is enabled (ESPSTF := Y), the
relay provides SOTF protection for a single-pole open (SPO) condition.
Table 3.114 SOTF Settings
Setting Description Range
Default
(5 A)
ESOTF Switch-onto-fault Y, N Y
ESPSTF Single-pole switch-onto-fault Y, N N
EVRST Switch-onto-fault voltage reset Y, N N
VRSTPU
a
a
This setting is hidden when EVRST = N.
Switch-onto-fault reset voltage (0.60–1.00 pu) 0.60–1.00 pu 0.8
52AEND 52A pole open time delay (cycles) OFF, 0.000–16000 10.000
CLOEND CLSMON or single-pole open delay
(cycles)
OFF, 0.000–16000 OFF
SOTFD Switch-onto-fault enable duration (cycles) 0.500–16000 10.000
CLSMON Close signal monitor SEL
OGIC equation NA
Ta b l e 3.1 1 5 S OT F Re l a y Wo rd B i t s
Name Description
SOTFE Switch-onto-fault trip logic enabled