Schweitzer Engineering Laboratories SEL-700G Series, Инструкция по эксплуатации

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Date Code 20170814 Instruction Manual SEL-700G Relay
Protection and Logic Functions
Global Settings (SET G Command)
Digital Input
Debounce
To comply with different control voltages, the SEL-700G offers dc and ac
debounce modes. Therefore, if the control voltage is dc, select the dc mode of
operation, and if the control voltage is ac, select the ac mode of operation. In
general, debounce refers to a qualifying time delay before processing the
change of state of a digital input. Normally, this delay applies to both the
processing of the debounced input when used in device logic, and to time
stamping in the SER. Following is a description of the two modes.
DC Mode Processing (DC Control Voltage)
Figure 4.145 shows the logic for the dc debounce mode of operation. To select
the dc mode of debounce, set IN101D to any number between 0 and 65000
ms. In the figure, Input IN101 becomes IN101R (internal variable), after
analog-to-digital conversion. On assertion, IN101R starts the debounce timer,
and the logic produces Relay Word bit IN101 after the debounce time delay.
The debounce timer is a pickup/dropout combination timer, with debounce
setting IN101D applying to both pickup (pu) and dropout (do) timers; you
cannot set any timer individually. For example, a setting of IN101D := 20 ms
delays processing of the input signal by 20 ms (pu) and maintains the output
of the timer (do) for 20 ms. Relay Word bit IN101 is the output of the
debounce timer. If you do not want to debounce a particular input, you can
still use Relay Word bit IN101 in logic programming, but you must set the
debounce time delay to 0 (IN101D := 0).
Figure 4.145 DC Mode Processing
AC Mode Processing (AC Control Voltage)
Figure 4.146 shows IN101R from Input IN101 applied to a pickup/dropout
timer. As opposed to the dc mode, there are no time settings for the debounce
timer in the ac mode: the pickup time delay is fixed at 2 ms, and the dropout
time is fixed at 16 ms. Relay Word bit IN101 is the output of the debounce
timer. To select the ac mode of debounce, set IN101D := AC.
Figure 4.146 AC Mode Processing
Figure 4.147 shows a timing diagram for the ac mode of operation. On the
rising edge of IN101R, the pickup timer starts timing (points marked 1 in
Figure 4.147). If IN101R deasserts (points marked 2 in Figure 4.147) before
expiration of the pickup time setting, Relay Word bit IN101 does not assert,
but remains at logical 0. If, however, IN101R remains asserted for a period
longer than the pickup timer setting, then Relay Word bit IN101 asserts to a
logical 1.
Input IN101
IN101R
Analog/Digital
Converter
pu
do
IN101
Relay
Word
Bit
Debounce Timer
2 ms
16 ms
IN101
Relay
Word
Bit
IN101R
Debounce Timer