User Guide

3
System Manager
Operation/Extended Operation
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Siemens User Guide Version 2.1 A6V10415471_en_a_21
Building Technologies 2015-07-15
 Acknowledge
 Change command priority
 Coldstart
 Enable/disable
 On/Off
 In service/Out of service
 Override/Release
 Reset value for equipment runtime
 Set a new point value
 Upload
Display of Properties
Properties display in one of two ways—automatically or manually. They display
automatically when a property goes into an off-normal state, and they display
manually when you select an object(s) in the system.
Why Command a Property?
You command a property to change its current state. For example, you might
command to initiate an action, enable or disable a property, acknowledge or reset
the status of a property, or override or release an override of a control program.
Commanding a property is also useful under these conditions:
 User action is required to manage an emergency
 When an alarm indicates a malfunctioning device
 When performing preventive maintenance
 To save energy
 When managing runtime totalization
Example of Commanding
At your facility, you want to change the temperature from 68 to 73°F (20 to
22.78°C) in a conference room on your floor. Using your building control software,
you send a command to change the Present Value of the Temperature Setpoint
object of the room to override the normal system control.
3.4.1.2 Command Priorities and Priority Arrays
Some objects in your building control system use specialized command priorities to
determine whether an operator or a particular control program is in control.
Command Priority
The Present Values of six object types in your building control system are based on
a command priority and established in a hierarchy that ranks from highest (1 –
Manual Life Safety) to lowest (16 - Available). The six object types are Analog
Output, Analog Value, Binary Output, Binary Value, Multi-State Output, and Multi-
State Value. The hierarchy helps determine which source has priority over another
to change the value of an object. To command one of these object types, you—or
an application—must have a command priority equal to or greater than the current
command priority of the object.
Command Priority Array
The Command Priority Array displays commands that have been issued at various
priority levels. Users and applications can set or relinquish (release) commands for
a commandable object. If the Present Value of an object has a Command Priority
Array, the appropriate priority level is commanded or relinquished when you
execute a command. If the Present Value of an object does not have a Command