Binary Input object (BI)

The Binary Input (BI) object type defines a standardized object whose properties represent the externally visible characteristics of a binary input. A "binary input" is a physical device or hardware input that can be in only one of two distinct states. In this description, those states are referred to as ACTIVE and INACTIVE. A typical use of a binary input is to indicate whether a particular piece of mechanical equipment, such as a fan or pump, is running or idle. The state ACTIVE corresponds to the situation when the equipment is on or running, and INACTIVE corresponds to the situation when the equipment is off or idle.

In some applications, electronic circuits may reverse the relationship between the application-level logical states ACTIVE and INACTIVE and the physical state of the underlying hardware. For example, a normally open relay contact may result in an ACTIVE state when the relay is energized, while a normally closed relay contact may result in an INACTIVE state when the relay is energized. The Binary Input object provides for this possibility by including a Polarity property.

BI object properties are:

✳ Indicates a Siemens proprietary property.

Present value

 

 

'Present value' indicates the present value of the virtual variable.

Property ID: 85

Tracking value

 

 

'Tracking value' represents the uncorrected value as measured by the subsystem. It has the same data type as the 'Present value'.

  • It is not limited by 'Present minimum value' and 'Present maximum value'.
  • It is not corrected by the correction factor and offset.
  • It is updated, even if "Out of service" = 'True' applies.

Property ID: 5107

State flag ✳

 

 

"State flag" represents four boolean flags ("Out of service", "Overridden", "Fault", "In-Alarm") that indicate the general status of an object.

Reliability

 

 

'Reliability' indicates whether the property value 'Present value' is reliable. If the 'Present value' is not reliable, the property 'Reliability' indicates the cause of the fault and the bit "Fault" of the state indication is set to 'True'. In a normal case, the property 'Reliability' is set to "No fault".

Property ID: 103

Out of service

 

 

"Out of service" allows decoupling the object from being modified by a control program, system program or peripheral device.

  • If "Out of service" is TRUE, the properties "Present value" and "Reliability" will no longer be updated by the respective control program, system program or peripheral device.
  • If "Out of service" is TRUE, the properties "Present value" and "Reliability" can be modified for simulating and testing purposes.
  • If "Out of service" will be changed from FALSE to TRUE, the properties "Present value" and "Reliability" keep their values. Nevertheless, they can be individually modified afterwards.
  • If "Out of service" will be changed from TRUE to FALSE, the properties "Present value" and "Reliability" keep their values. They will be modified by the next update of the producer.

Property ID: 81

Field device type

 

 

"Field device type" is a text description of the physical peripheral device connected to the input or output. Typically contains the product part number of the connected device. To be completed by the engineer. Is not used by the data acquisition.

Example: QAX3.P84 (room unit) - Entrance

I/O address ✳

 

 

"I/O address" identifies and documents the data source, and facilitates configuring, modifying, and querying the assignment in a standardized way.

The content of "I/O address" is technology-specific and includes:

  • Unique selector to identify and document the respective data acquisition. For example, TX-I/O or KNX PL-Link.
  • Unique address to identify the peripheral data source. For example, TX-I/O 3.4.
  • Blank until assigned to a Module.

Commissioning state ✳

 

 

"Commissioning state" is an enumerated value representing the commissioning state (Not checked, Check failed, Check successful) of the BACnet object.

Typically set during commissioning by means of engineering and commissioning function (for example, Automation Building Tool or installer tool). It can be inspected by engineering and commissioning, or operation and monitoring functions, and used in commissioning reports.

Commissioning information ✳

 

 

"Commissioning information" indicates additional, human-readable information about the BACnet object's commissioning state. For example, "cable defect".

Typically set during commissioning by means of engineering and commissioning function (for example, Automation Building Tool or installer tool). It can be inspected by engineering and commissioning, or operation and monitoring functions, and used in commissioning reports.

Polarity

 

 

'Polarity' displays the mapping of property 'Present value' to the physical state of the contact.

  • If property 'Polarity' is normal, the active state of property 'Present value' is also the state "Closed" of the contact. The contact is "NO".
  • If property 'Polarity' is inverted, the active state of property 'Present value' is also the state "Open" of the contact. The contact is "NC".

Property ID: 84

Inactive text

 

 

'Inactive text' describes the inactive state of property 'Present value'.

Property ID: 46

Active text

 

 

'Active text' describes the active state of property 'Present value'.

Property ID: 4

Subsystem ✳

 

 

"Subsystem" uniquely identifies the respective BACnet object type extension of a BACnet object type.

Several BACnet object type extensions might be available for Engineering thus proposed for selection. None or one extension might be selected, thus be supported at runtime.

Object access level ✳

 

 

"Object access level" defines the instance-specific object access level. "Object access level" is used for generic filtering and processing an object by a client application.

  • "Object access level" is a configuration property which can only be set up offline (ABT, application configuration).
  • "Object access level" is evaluated by client applications such as Technical Operator, DB-Import, and APOGEE Point Team mapping.

Access level

Name

Description

7

Basic operation

Access to BACnet objects and properties for a room user e.g. data points visible on a room unit.

6

Standard operation

Access to BACnet objects and properties for standard operation and monitoring (daily business), .e.g. room and plant information on a management station.

5

Extended operation

Access to BACnet objects and properties for extended operation and monitoring such as network and device objects. All I/Os are visible

4

Administrator

Not used by HQ solutions yet.

3

Basic service

Access to BACnet objects and properties used for commissioning, e.g. configuration value extensions, I/O extensions, etc.

2

Extended service

Not used by HQ solutions yet.

1

Internal

Access to all BACnet objects and properties for very specialized actions e.g. during development.

Object usage ✳

 

 

"Object usage" indicates whether the object is used or unused. The "Object usage" property can hide or display respective objects and their functionality in a client. For example, room functionality can be marked for flexible room arrangements as used/unused. An object that is marked as unused behaves as if the object does not exist.

Property ID: 4930

Description

 

 

"Description" is a string of printable characters whose content is not restricted.

Object name

 

 

"Object name" represents a name for the object that is unique internetwork-wide. The minimum length of the string is one character. The set of characters used in the "Object name" are restricted to printable characters.

Comment

 

 

A string of printable characters whose content is not restricted.