PointSchemes
The PointSchemes element is the parent node that defines the Point Scheme used in the CygNet installation. This property is available for selection in the Point scheme drop-down menu on the General page of the PNT Editor. Options include CygNet Standard, CygNet Enhanced (available only as a separately licensable entity), or some other user-defined Point Scheme.
Properties
The following table lists and describes the properties of the PointSchemes element.
| Property | Description |
|---|---|
|
Case Sensitive |
Yes |
|
Required |
Yes |
|
Number of Instances Allowed |
1 |
|
Requires End Tag |
Yes |
|
Parent Element |
|
|
Child Element |
PointScheme
The PointScheme element contains the attributes that define the Point Scheme used in the CygNet installation and the actual point types available for configuration.
Properties
The following table lists and describes the properties of the PointScheme element.
| Property | Description |
|---|---|
|
Case Sensitive |
Yes |
|
Required |
Yes |
|
Number of Instances Allowed |
1 - 16 |
|
Requires End Tag |
Yes |
|
Parent Element |
|
|
Child Element |
|
|
Attributes |
id desc blink oldsinglecolorblink enumooraction histvaluecount (Enhanced Point Scheme only) |
Attributes
The following table lists and describes attributes generally applicable to the PointScheme element.
| Attribute | Description |
|---|---|
|
id |
The Point Scheme id. A CvsMetadata file can define up to 16 custom Point Schemes (Schemes 0 -15). The id attribute associates the Point Scheme definition with one of the 16 available custom schemes. (See Point Scheme). Note: If the CygNet Standard Point Scheme is used, its default is Scheme 0. Value:
|
|
desc |
The description of the Point Scheme. |
|
blink |
The blink method associated with the [DisplayAlarmAck] property for a point in an unacknowledged alarm state when displayed on a CygNet Studio screen. Possible values are as follows.
|
|
oldsinglecolorblink |
This attribute is obsolete and is provided only for backwards compatibility support with CygNet Studio. Value:
|
|
enumooraction |
Sets the behavior of an enumerated point if an attempt is made to set the current value of the point and the value is out-of-range. There are three options:
|
|
histvaluecount |
Applies only to the CygNet Enhanced Point Scheme. Specifies the number of values for all enabled historized config bits that can be stored in the CVS. CygNet will perform any alarm calculations against those values. The default value is 60; the maximum value is 600. Note that specifying a very high value for histvaluecount will increase the memory utilization of the CVS and possibly affect performance adversely. Best practice recommends that you create a custom point scheme when using this attribute so as to not interfere with any existing point scheme used by your enterprise. Note that the number of historized calculation type values stored in the CVS for a Standard Point Scheme is fixed at 60 entries and cannot be edited. See Alarm Calculation Types for more information. |
Point Types
Each Point Scheme has a defined set of point types that designate which types are available for a particular Point Scheme: Analog, Digital, String, and Enumeration. The list can be found in the Point type drop-down menu on the General page of the PNT Editor. The point type chosen determines which Status Bits and Point State Instances are used for the point.
Example
The following example designates input and output point types for Analog, Digital, String, and Enumeration points. Note that there is no functional difference between an input point type and an output point type.
|
<PointSchemes> <PointScheme id="" desc="" blink="" oldsinglecolorblink="" enumooraction="" histvaluecount="180"> <AI/> <AO/> <DI/> <DO/> <SI/> <SO/> <EI/> <EO/> </PointScheme> </PointSchemes> |
