Schweitzer Engineering Laboratories SEL-351-5, Instruction Manual

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7.3
Date Code 20070117
Instruction Manual SEL-351-5, -6, -7 Relay
Inputs, Outputs, Timers, and Other Control Logic
Optoisolated Inputs
Figure 7.2 Example Operation of Optoisolated Inputs IN201–IN208—
Extra I/O Board (Models 0351x1 and 0351xY)
Input Debounce
Timers
See Figure 7.1 .
Each input has settable pickup/dropout timers (IN101D–IN106D) for input
energization/de-energization debounce. Note that a given time setting (e.g.,
IN101D = 0.50) is applied to both the pickup and dropout time for the
corresponding input.
Time settings IN101D–IN106D are settable from 0.00 to 1.00 cycles, or ac.
The relay takes the entered time setting and internally runs the timer at the
nearest 1/16 cycle. For example, if setting IN105D = 0.80, internally the timer
runs at the nearest 1/16 cycle: 13/16 cycles (13/16 = 0.8125).
The ac setting allows the input to sense ac control signals. The input has a
maximum pickup time of 0.75 cycles and a maximum dropout time of
1.25 cycles. The ac setting qualifies the input by not asserting until two
successive 1/16 cycle samples are higher than the optoisolated input voltage
threshold and not deasserting until sixteen successive 1/16 cycle samples are
lower than the optoisolated input voltage threshold.
For most dc applications , the input pickup/dropout debounce timers should be
set in 1/4 cycle increments. For example, in the factory default settings , all the
optoisolated input pickup/dropout debounce timers are set at 1/2 cycle (e.g.,
IN104 = 0.50). See
SHO Command (Show/View Settings) on page 10.26 for a
list of the factory default settings.
Only a few applications (e.g., communications-assisted tripping schemes)
might require input pickup/dropout debounce timers set less than 1/4 cycle
[e.g., if setting IN105D = 0.13, internally the timer runs at the nearest
1/16 cycle: 2/16 cycles (2/16 = 0.1250)].
Open
IN201 IN201 Logical 0 De-energized
Opto-
isolated
Inputs
Example
Switch
States
Built-in
Debounce
Timers
Relay
Word
Bits
Relay
Word Bit
States
Optoisolated
Input States
(+)
(—)
IN201D
IN201D
Closed
IN202 IN202 Logical 1 Energized
IN202D
IN202D
Closed
IN203 IN203 Logical 1 Energized
IN203D
IN203D
Open
IN204 IN204 Logical 0 De-energized
IN204D
IN204D
Open
IN205 IN205 Logical 0 De-energized
IN205D
IN205D
Open
IN206 IN206 Logical 0 De-energized
IN206D
IN206D
Closed
IN207 IN207 Logical 1 Energized
IN207D
IN207D
Open
IN208 IN208 Logical 0 De-energized
IN208D
IN208D