The usual conversions performed by OPC Data Client on the data take place. For details, see:

Data Types in OPC Classic

• Data Types in OPC Classic
• Data Types in OPC-UA

In addition, the Connectivity RTD Server makes following conversions before returning the data through the RTD function:

• Null values are converted to empty strings.
• Generic objects are converted to their string representations.
• 64-bit and wider integers and decimals are converted to strings (this avoids loss of precision).

 Dates and Times

The dates and times are represented as floating point number in Excel internally, and are transferred as such to Excel from the Connectivity RTD Server. When dates or times from the Connectivoty RTD Server are displayed by Excel, by default the general number format is used. You need to set the cell format manually as needed. For example, you can use one of the pre-defined Date or Time formats that Excel offers, or a custom format, like (e.g.):

   m/d/yyyy h:mm:ss AM/PM

You may also want to read: Format numbers as dates or times.