According to the BACnet protocol documentation:

Records event notifications with timestamps and other pertinent data in an internal buffer for subsequent retrieval. Each timestamped buffer entry is called a "log record."

Objects of type eventLog have the following properties:

•ackedTransitions

•bufferSize

•description

•enable

•eventAlgorithmInhibit

•eventAlgorithmInhibitRef

•eventDetectionEnable

•eventEnable

•eventMessageTexts

•eventMessageTextsConfig

•eventState

•eventTimeStamps

•lastNotifyRecord

•logBuffer

•notificationClass

•notificationThreshold

•notifyType

•objectIdentifier

•objectName

•objectType

•profileLocation

•profileName

•propertyList

•recordCount

•recordsSinceNotification

•reliability

•reliabilityEvaluationInhibit

•startTime

•statusFlags

•stopTime

•stopWhenFull

•tags

•totalRecordCount