BACnet_BO

The Binary Output object type (WinCC OA data point type) defines a standardized object whose properties represent the externally visible characteristics of a binary output. A "binary output" is a physical device or hardware output 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 output is to switch a particular piece of mechanical equipment, such as a fan or pump, on or off. 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 (Polarity = NORMAL).

In some applications, it may happen that these logical states are reversed on the application-level (Polarity = REVERSE).

Data point Type Name

BACnet_BO

(Object/)Data point Type Structure

DP_Name.property

Data Point Element (Property)

Data Type

Device-depending availability

Description

Present_Value

unsigned integer

This property reflects the logical state of the Binary Output. The logical state of the Input can be either INACTIVE or ACTIVE. The relationship between the Present_Value and the physical state of the Output is determined by the Polarity property.

The possible states are summarized as follows:


Relation	PSoD
PV = I P = N PSoI = OFF or I	not running
PV = A P = N PSoI = ON or A	running
PV = I P = R PSoI = ON or A	not running
PV = A P = R PSoI = OFF or I	running

PV = Present_Value

P = Polarity

PSoI = Physical State of Input

PSoD = Physical State of Device

A = ACTIVE

I = INACTIVE

N = NORMAL

R = REVERSE

Faceplate

The state of Present_Value that is shown in the faceplate has the following meaning: green = ACTIVE (1) and gray = INACTIVE (0). When the hand mode is activated, the present state can be changed directly in the faceplate. For more details, see Value Input Panel.

Tabs

For more information on tabs, see Tabs.

Available Symbol Types


Name	Usage	$ Parameter	Symbols
Simple_BO	State display in terms of color. Switching (e.g. switch command on/off, control command open/closed)	DP
Lamp_1	Light bulb (on/off)	DP