Honeywell Uniformance R300, User Manual

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5 Using the PHD OPC Server
5.4
PHD OPC Data Standards for Client Applications
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Uniformance - PHD OPC Server User Guide
PHD OPC name forms
You can access data items by name using the OPC standard interfaces. The PHD OPC Server
accepts item names as identifiers of PHD Server tags. The name syntax is a free form text
string.
Item name conventions
The system-wide naming conventions used to identify a DCS point.variable must be
consistent throughout all system components. Variable names configured in the DCS must
match, and be closely coordinated with those configured in PHD Server database.
PHD tag name conventions
REFERENCE: For PHD tag naming conventions, refer to the Tag Configuration form in the
PHD User Guide (pim0201).
Supported data types
The following table shows the supported data types common to Honeywell, and how the PHD
OPC Server maps them into OPC data.
The PHD OPC Server supports access of the following data types. In the case where the
source attribute is set to BARRAY the OPC Server will return an array of values. The actual
data type will depend on the data stored in PHD, since the data is actually stored as a Safe
Array and can contain different data types. Otherwise each item maps to a single PHD tag
whether or not it came from an array on the source system.
This Honeywell data type… Maps to this OPC type…
Real – 32 bit IEEE format (float) VT_R4
Real – 64 bit IEEE format (double) VT_R8
Standard and Self Defining Enumeration VT_BSTR
Ordinal VT_I4
String VT_BSTR
Integer – 32 bit signed VT_I4
Integer – 64 bit signed VT_CY
Binary – SRC_ATTRIB is set to BARRAY VT_* | VT_ARRAY
Binary – All other cases VT_UI1 | VT_ARRAY