OpcPropertyID.Enumeration Enumeration

Represents the internal enumeration of the OpcPropertyID structure.

[Visual Basic]
 Public
   Enum OpcPropertyID.Enumeration
[C#]
 public enum OpcPropertyID.Enumeration
[C++]
 __value public enum
   OpcPropertyID.Enumeration

Remarks

Internal representation for the OpcPropertyID structure.

Members

Member Name Short Value Equivalent

AccessRights Item Access Rights

AlarmAreaList
Alarm Area List

An array of stings indicating the plant or alarm areas which include this ItemID.

AlarmQuickHelp
Alarm Quick Help

A short text string providing a brief set of instructions for the operator to follow when this alarm occurs.

CloseLabel
Contact Close Label

Present only for `discrete' data. This represents a string to be associated with this contact when it is in the closed (non-zero) state

e.g. "RUN", "CLOSE", "ENABLE", "SAFE" ,etc.

ConditionLogic
Condition Logic

An arbitrary string describing the test being performed.

e.g. "High Limit Exceeded" or "TAG.PV >= TAG.HILIM"

ConditionStatus
Condition Status

The current alarm or condition status associated with the Item

e.g. "NORMAL", "ACTIVE", "HI ALARM", etc

DataType Item Canonical DataType

Description
Item Description

e.g. "Evaporator 6 Coolant Temp"

DeviationLimit Deviation Limit

EngineeringUnits
EU Units

e.g. "DEGC" or "GALLONS"

EUInfo
Item EUInfo

If EUType is "Enumerated" - EUInfo will contain an array of strings (VT_ARRAY | VT_BSTR) which contains a list of strings (Example: "OPEN", "CLOSE", "IN TRANSIT", etc.) corresponding to sequential numeric values (0, 1, 2, etc.)

EUType Item EU Type

HighEU
High EU

Present only for `analog' data. This represents the highest value likely to be obtained in normal operation and is intended for such use as automatically scaling a bargraph display.

e.g. 1400.0

HighIR
High Instrument Range

Present only for `analog' data. This represents the highest value that can be returned by the instrument.

e.g. 9999.9

HiHiLimit HiHi Limit

HiLimit Hi Limit

LimitExceeded
Limit Exceeded

For multistate alarms, the condition exceeded

e.g. HIHI, HI, LO, LOLO

LoLimit Lo Limit

LoLoLimit LoLo Limit

LowEU
Low EU

Present only for `analog' data. This represents the lowest value likely to be obtained in normal operation and is intended for such use as automatically scaling a bargraph display.

e.g. -200.0

LowIR
Low Instrument Range

Present only for `analog' data. This represents the lowest value that can be returned by the instrument.

e.g. -9999.9

OpenLabel
Contact Open Label

Present only for `discrete' data. This represents a string to be associated with this contact when it is in the open (zero) state

e.g. "STOP", "OPEN", "DISABLE", "UNSAFE" ,etc.

PrimaryAlarmArea
Primary Alarm Area

A string indicating the primary plant or alarm area including this ItemID

Quality
Item Quality

This will behave like a read from DEVICE.

RateChangeLimit Rate of Change Limit

ScanRate
Server Scan Rate

In Milliseconds. This represents the fastest rate at which the server could obtain data from the underlying data source. The nature of this source is not defined but is typically a DCS system, a SCADA system, a PLC via a COMM port or network, a Device Network, etc. This value generally represents the `best case' fastest RequestedUpdateRate which could be used if this item were added to an OPCGroup. The accuracy of this value (the ability of the server to attain `best case' performance) can be greatly affected by system load and other factors.

SoundFile
Sound File

e.g. C:\MEDIA\FIC101.WAV, or .MID

TimeConsistencyWindow

Timestamp
Item Timestamp

This will behave like a read from DEVICE.

TimeZone
Item Timezone

The difference in minutes between the items UTC Timestamp and the local time in which the item value was obtained. See the OPCGroup TimeBias property. Also see the WIN32 TIME_ZONE_INFORMATION structure.

Value
Item Value

Note the type of value returned is as indicated by the "Item Canonical DataType" above and depends on the item. This will behave like a read from DEVICE.

For more information, see the topic OPC OPC Item Properties.

Requirements

Namespace: Visavi.Opc.Client

Platforms: Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows .NET Server family

Assembly: Visavi.Opc.Client

Member Name	Short Value Equivalent
AccessRights	Item Access Rights
AlarmAreaList	Alarm Area List An array of stings indicating the plant or alarm areas which include this ItemID.
AlarmQuickHelp	Alarm Quick Help A short text string providing a brief set of instructions for the operator to follow when this alarm occurs.
CloseLabel	Contact Close Label Present only for `discrete' data. This represents a string to be associated with this contact when it is in the closed (non-zero) state e.g. "RUN", "CLOSE", "ENABLE", "SAFE" ,etc.
ConditionLogic	Condition Logic An arbitrary string describing the test being performed. e.g. "High Limit Exceeded" or "TAG.PV >= TAG.HILIM"
ConditionStatus	Condition Status The current alarm or condition status associated with the Item e.g. "NORMAL", "ACTIVE", "HI ALARM", etc
DataType	Item Canonical DataType
Description	Item Description e.g. "Evaporator 6 Coolant Temp"
DeviationLimit	Deviation Limit
EngineeringUnits	EU Units e.g. "DEGC" or "GALLONS"
EUInfo	Item EUInfo If EUType is "Enumerated" - EUInfo will contain an array of strings (VT_ARRAY \| VT_BSTR) which contains a list of strings (Example: "OPEN", "CLOSE", "IN TRANSIT", etc.) corresponding to sequential numeric values (0, 1, 2, etc.)
EUType	Item EU Type
HighEU	High EU Present only for `analog' data. This represents the highest value likely to be obtained in normal operation and is intended for such use as automatically scaling a bargraph display. e.g. 1400.0
HighIR	High Instrument Range Present only for `analog' data. This represents the highest value that can be returned by the instrument. e.g. 9999.9
HiHiLimit	HiHi Limit
HiLimit	Hi Limit
LimitExceeded	Limit Exceeded For multistate alarms, the condition exceeded e.g. HIHI, HI, LO, LOLO
LoLimit	Lo Limit
LoLoLimit	LoLo Limit
LowEU	Low EU Present only for `analog' data. This represents the lowest value likely to be obtained in normal operation and is intended for such use as automatically scaling a bargraph display. e.g. -200.0
LowIR	Low Instrument Range Present only for `analog' data. This represents the lowest value that can be returned by the instrument. e.g. -9999.9
OpenLabel	Contact Open Label Present only for `discrete' data. This represents a string to be associated with this contact when it is in the open (zero) state e.g. "STOP", "OPEN", "DISABLE", "UNSAFE" ,etc.
PrimaryAlarmArea	Primary Alarm Area A string indicating the primary plant or alarm area including this ItemID
Quality	Item Quality This will behave like a read from DEVICE.
RateChangeLimit	Rate of Change Limit
ScanRate	Server Scan Rate In Milliseconds. This represents the fastest rate at which the server could obtain data from the underlying data source. The nature of this source is not defined but is typically a DCS system, a SCADA system, a PLC via a COMM port or network, a Device Network, etc. This value generally represents the `best case' fastest RequestedUpdateRate which could be used if this item were added to an OPCGroup. The accuracy of this value (the ability of the server to attain `best case' performance) can be greatly affected by system load and other factors.
SoundFile	Sound File e.g. C:\MEDIA\FIC101.WAV, or .MID
TimeConsistencyWindow
Timestamp	Item Timestamp This will behave like a read from DEVICE.
TimeZone	Item Timezone The difference in minutes between the items UTC Timestamp and the local time in which the item value was obtained. See the OPCGroup TimeBias property. Also see the WIN32 TIME_ZONE_INFORMATION structure.
Value	Item Value Note the type of value returned is as indicated by the "Item Canonical DataType" above and depends on the item. This will behave like a read from DEVICE.

OpcPropertyID.Enumeration Enumeration

Remarks

Members

Requirements

See Also