This function is used in Python Scripting.


Reads raw values from the OPC-HDA server.

Client Permission Restrictions

This scripting function has no Client Permission restrictions.


system.opchda.readRaw(serverName, itemIds, startDate, endDate, maxValues, boundingValues)

  • Parameters

String serverName - The name of the defined OPC-HDA server to read.

List itemIds - A list of item ids to read.

Object startDate - The starting date/time of the query.

Object endDate - The ending date/time of the query.

Integer maxValues - The maximum number of values to return. 0 or less means unlimited.

Boolean boundingValues - A boolean indicating whether or not the "bounding values" should be included in the result set. The bounding values provide a value exactly at the start and end dates, but may be resource-intensive to retrieve.

  • Returns

List[ReadResults] - A list of read results which is one-to-one with the item IDs passed in. The ReadResult object has a 'serviceResult' quality property that indicates whether the call was successful, and is itself a list of QualifiedValues.

  • Scope

Gateway, Vision Client, Perspective Session

Code Examples
Code Snippet
# This example will read raw data from a Matrikon server between two specified dates.
# Declare start and end dates
start =, 3, 14)
end =

# Call system function and print results
readValue = system.opchda.readRaw("Matrikon",[1],start,end,0,False)
print readValue

system opchda readRaw, opchda.readRaw