GE LPS-D, Инструкция по эксплуатации

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13-
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LPS-D Line Protection System GE Power Management
13.2 DESIGN CONSIDERATIONS 13 XPRESSION BUILDER
13
Figure 13–4: PICKUP DELAY TIMER
d) COUNTERS
The counter has two input line, one output line, and a user selected count threshold (in milliseconds) as shown
in Figure 13–5: COUNTER. A transition from low (binary 0) to high (binary 1) on the S input line increments the
counter by a value of one. The O output line is high (binary 1) when the accumulated count is equal to or
greater than the count threshold. If the O output line is low (binary 0), then the accumulated count is less than
the set value. A transition from low (binary 0) to high (binary 1) on the R input line resets the counter to zero.
Figure 13–5: COUNTER
Table 13–1: PICKUP DELAY TIMER TRUTH TABLE
S R Previous Timer State Current Timer State RO SO
L L NOT TIMING NOT TIMING RO
n-1
L
↑
L NOT TIMING TIMING DOWN L L
X L TIMING DOWN TIMER EXPIRED L H
X H TIMING DOWN TIMER RESET H L
X
↑
NOT TIMING NOT TIMING L L
1000
R
S S O
R O
0 0 0 0
S
R
O
5