Chapter Three
Operation
man_105_2.9.doc
Page
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or "noisy" signals. The input is filtered with a 1 second time constant and a 1 second
debounce. The analogue outputs are filtered with a 1 second time constant. An example
explaining the interaction of these figures is shown below. In general, the following may be
used as a rule of thumb for calculating the appropriate sensitivity required for a given
application:
Instantaneous change of 2 x sensitivity on input
→
3 second output response
Instantaneous change of 10 x sensitivity on input
→
5 second output response
The analogue inputs have 15 bit resolution and 0.016mA accuracy.
An
example
of an
analogue
input and how the output follows it is shown below:
Pulse input change of state
Pulse input counts
do not use “change-of-state” transmissions. Instead, accumulated pulse
input counts are transmitted at set intervals. The default period is 1 minute and is
E
0.5 sec
0.5 sec
0.5 sec
SENSITIVITY
BAND
A
B
C
D
UPDATE
TIME
INPUT
SIGNAL
OUTPUT
SIGNAL
TIME
A
No transmission as the sensitivity band was not exceeded
B
The sensitivity band was exceeded, however the input returned to within the
sensitivity band before the 0.5 sec debounce time - no transmission
C
Transmission occurs 0.5 sec after the sensitivity band is exceeded.
D
Another transmission 0.5 sec later as the input has changed by more than
the sensitivity band
E
The input has not changed by more than the sensitivity, however the update
time has elapsed since D.
