Schweitzer Engineering SEL-351P, Быстрый старт

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7-28 Inputs, Outputs, Timers, and Other Control Logic Date Code 990215
SEL-351P Manual Técnico
If the individual settings change causes a change in one or more SEL
OGIC
Control Equation
settings SS1 through SS6, the active setting group can be changed, subject to the newly enabled
SS1 through SS6 settings.
Note: Make Active Setting Group Switching Settings with Care
The active setting group is stored in nonvolatile memory so it can be retained during power loss
or settings change. The nonvolatile memory is rated for a finite number of “writes” for all setting
group changes. Exceeding this limit can result in an EEPROM self-test failure. This limit
translates to an average of 10 setting groups changes per day for a 25-year relay service life.
This requires that SEL
OGIC
Control Equation settings SS1 through SS6 (see Table SECTION 7:
.4) be set with care. Settings SS1 through SS6 cannot result in continuous cyclical changing of
the active setting group. Time setting TGR qualifies settings SS1 through SS6 before changing
the active setting group. If optoisolated inputs IN101 through IN106 are used in settings SS1
through SS6, the inputs have their own built-in debounce timer that can help in providing the
necessary time qualification (see Figure SECTION 7: .1).
SEL
OGIC
C
ONTROL
E
QUATION
V
ARIABLES
/T
IMERS
Sixteen (16) SEL
OGIC
Control Equation variables/timers are available. Each SEL
OGIC
Control
Equation variable/timer has a SEL
OGIC
Control Equation setting input and variable/timer outputs
as shown in Figure SECTION 7: .23 and Figure SECTION 7: .24.
Timers SV1T through SV6T in Figure SECTION 7: .23 have a setting range of a little over 4.5
hours:
0.00 - 999999.00 cycles in 0.25-cycle increments
Timers SV7T through SV16T in Figure SECTION 7: .24 have a setting range of almost 4.5
minutes:
0.00 - 16000.00 cycles in 0.25-cycle increments
These timer setting ranges apply to both pickup and dropout times (SVnPU and SVnDO,
n = 1 through 16).