An Item of Digital Input type (Digital Input) represents a physical or logical point having binary state (on / off, open / closed, 1/0, etc..) monitored by the system.


The configuration of the parameters of the Item allows you to define how the value of the Item will be processed. In particular, it is possible to define:


    1. the condition of alarms generation 
    2. the strings to replace the states "On" and Off "the Item


This icon marks the tool that allows the insertion of a DI item: 



The data specific to an Item of Digital Input type are:

 

Address Category

 

Invert

Indicates that the value of the item in the database has to be inverted with respect to the value read from the device (reading 1 on the device the item is set to 0, by writing 1 a 0 is sent to the device, and vice versa).

This option is particularly useful, for example, to program a different state of “normal” of the electrical contacts (NC, NO), without altering the logic of the project.

This feature is implemented by the driver, and it might not be supported on some devices.


For more information, please refer to the manual of the driver used.


Alarm conditions category

 

Specifies the condition of generation of an alarm:


On

Enables the generation of alarms for the raising edge of the value.

Off

Enables generation of the alarm for the falling edge of the value.


Status naming category


ON

The name you assign to the ON status (e.g., Closed, Active, On). If not specified it is assumed the word "ON".

OFF

The name you assign to the OFF status (e.g. Open, Off, Off). If not specified it is assumed the word "OFF".