Westermo IDW-90, Руководство пользователя

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11 6620-2200
= t
a
High level trigged input timing
≥
t
a
Trig
Trig
= t
a
Low level trigged input timing
≥
t
a
Trig
No trig due to low
level shorter than t
a
= t
a
<t
a
Digital Input
The digital input gives the following functionality:
1.
Static input
A static digital level trigged input high or low triggers the Generic I/O. With a level
trigged input only the first entry in the Generic I/O list can be trigged by the I/O
input.
The input is trigged when
the selected level has been
stable for ta ms.
A new trig will not occur
until the input has return
to the opposite state an
back again.
2.
Pulsed Input
When input is set to edge trigged pulsed the number of pulses counted selects the
entry to be trigged.
For the pulsing of an input, some timings must be kept.
The input is filtered and pulses shorter than ta is discriminated. The time between
pulses must also be kept shorter than T
p
. One other restriction on T
p
. Is that T
p
.³ 2t
a
.
When time between pulses exceeds T
p
the number of pulses are accumulated and an
entry selected by number of pulses counted.
The parameter ta is also used when output pulsing is selected.
The parameters ta and t
P
are programmable from 10 ms to 2550 ms.
≥
t
a
≤
T
p
>T
p
≥
t
a
≤
T
p
>T
p
Positive edge trigged input timing
Negativ edge trigged input timing
Number of pulses counted
accumulated here