According to the BACnet protocol documentation:

Defines a standardized object whose properties represent a collection of other objects and one or more of their properties. A Global Group object is used to simplify the exchange of information between BACnet devices by providing a shorthand way to specify all members of the group at once. A Global Group object differs from a Group object in that its members can be from anywhere in the BACnet internetwork, it supports intrinsic event reporting, and it exposes a method for sending periodic COV notifications. The Global Group object is able to monitor all referenced Status_Flags properties to detect changes to non-normal states and can initiate an event notification message conveying the values of all of the members of the group. This provides a mechanism to define a large set of property values that are made available when an event occurs.

Objects of type globalGroup have the following properties:

•ackedTransitions

•clientCovIncrement

•covResubscriptionInterval

•covuPeriod

•covuRecipients

•description

•eventAlgorithmInhibit

•eventAlgorithmInhibitRef

•eventDetectionEnable

•eventEnable

•eventMessageTexts

•eventMessageTextsConfig

•eventState

•eventTimeStamps

•groupMemberNames

•groupMembers

•memberStatusFlags

•notificationClass

•notifyType

•objectIdentifier

•objectName

•objectType

•outOfService

•presentValue

•profileLocation

•profileName

•propertyList

•reliability

•reliabilityEvaluationInhibit

•requestedUpdateInterval

•statusFlags

•tags

•timeDelay

•timeDelayNormal

•updateInterval