44 GC250 Technical Manual
EAAM057608EN
5.8.3
Virtual digital inputs
In addition to the 4 digital physical inputs the controller also operates 16 virtual digital inputs
(from revision 01.07). The same are operated by the controller just as if they were physical
inputs (with no limitation), but the status of the virtual inputs is not acquired from the hardware,
but it is determined through the software. In fact, every digital input can have an AND/OR logic
associated, which determines its status.
A practical example of use. Suppose you want to activate a warning if the mains voltage
exceeds the tolerance thresholds. Let us use the virtual digital input #1 (as example).
Using the BoardPrg3 software we associate an AND/OR logic configured as AND to
the #1 virtual digital input, with the following list of conditions:
▪
ST.064 (“Status of the GCB”)
▪
ST.017 (“Mains out of tolerance or absent”).
The virtual digital input will therefore be active when the GCB is closed and the mains
is out of tolerance.
Let us set the DIF.4001
function (“Generic warning”) within the P.2151 parameter.
Let us set the desired delay (for example 0.5 s) within the P.2152 parameter.
5.8.4
Digital inputs configuration
By default, all the digital inputs are considered “active” when the related terminal is connected
to the
supply minus of the controller; they are considered “not active” when the related terminal
is not connected to anything.
The logic status of the input can be inverted with respect of
the physical status by selecting the box “Reverse polarity” in the input configuration
page on BoardPrg3.
The box is only visible if the function selected is other than DIF.0000
–
“Not used”.
It is also possible to invert the logic status (single based for each input), operating directly on
the controller using parameters P.2000 for inputs
T.16
...
T.19
and P.2100 (for the analogue
inputs when used as digital).
These parameters have a bit for each output:
A bit set to zero means that the related input is “active” when it is connected to the
negative supply of the controller.
A bit set to one means that the related inp
ut is considered “active” when it is not
connected to anything (it will become “not active” if it is disconnected to the supply
negative terminal of the controller).
By default, all bits are set to zero.
To each input two parameters are associated:
A parameter that configures the function of it (P.2001 for the input
T.16,
the
consecutive parameters for the other inputs).
A parameter that configures a possible delay of the function activation (P.2002 for the
input
T.16,
the consecutive parameters for the other inputs).
See documents [1] for the parameters list.
The parameter that configures the delay for an input is used by the controller only for some
input functions. The following chart highlights when it is used:
INFORMATION!: in BoardPrg3, the boxes for the delay is always displayed, even if
is not used by the controller.