36
1MRS750881-MUM
Remote Monitoring and Control Unit
Technical Reference Manual
REC 523
Dipo
Fig. 5.4.2.1.-1 Filtering of a digital input
In the figure above, the input signal is named “Input”, the filter timer “Filter” and
the filtered input signal “Filtered Input”. At the beginning, the input signal is at high
state, the short low state is filtered and no input status change is detected. The low
state starting from the time t
0
exceeds the filter time, which means that the change
in the input status is detected and the time tag attached to the input change is t
0
. The
high state starting from t
1
is detected and the time tag t
1
is attached.
Each digital input has a filter time parameter
Input # filter
, where “#” is the
number of the digital input of the module in question (for example Input 1 filter).
5.4.2.2.
Inversion of a digital input
The parameter
Input # invert.
can be used to invert a digital input:
When the digital input is inverted, the status of the input is TRUE (1) when no
control voltage is applied to its terminals. Accordingly, the input state is FALSE (0)
when a control voltage is applied to the terminals of the digital input.
5.4.2.3.
Pulse counters
Some specific digital inputs (refer to Section 5.4. Digital inputs) of REC 523 can be
programmed as digital inputs or as pulse counters. This programming is done via the
parameter
Input # mode
(in this parameter as well as in others mentioned below,
“#” denotes the input number).
Parameter
Values
Default
Input # filter
1....15000 ms
a
a. In the REC 523 revision F or later. In earlier revisions the value is 1...65535 ms.
5 ms
t
0
t
1
Filter Time
Filtered Input
Input
Filter Time
Control voltage
Input # invert.
Status of digital input
No
0
FALSE (0)
Yes
0
TRUE (1)
No
1
TRUE (1)
Yes
1
FALSE (0)
Parameter
Values
Default
Input # invert.
0 (not inverted)
0
1 (inverted)
