Measurement Computing PointScan Road Map rev.2.0 User Manual

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Address - Click on the (Hints) button and then the Hints window’s button for
detailed information on how to set the address. The IOtech PointScan hardware manuals provide

detailed MODBUS addressing information for each individual module type. For example, the

screen indicates that for Analog input you would use addresses in the range 300001 to 330000;

and for Discrete input you would use addresses in the range 100001 to 200000. The IOtech
PointScan modules use standard MODBUS addressing for I/O; however, KEPServer requires that

an additional (0) zero be placed in the MODBUS addressing scheme. The KEPServer address is a

factor of 10 higher than the standard MODBUS address for that I/O type and channel.

Example: The MODBUS address of the third analog input channel on a PointScan /100 series

module is 30003. You will enter 300003 as the address for that tag in KEPServer.

The tag address must be unique within each PointScan module. So if you have a second

PointScan module with analog inputs, you would start over again with address 300001.

Description - This is a comment field (not required). Any alphanumeric string up to 64 characters

can be used.

Data Type - If the OPC client is DASYLab, then the process variables in KEPServer must be

configured for short data format, since DASYLab can recognize only the short data format.

Client Access - If the tag is an analog or digital input, then Client Access should be set to Read-

Only. If the tag is an analog or digital output, then Client Access should be set to Read/Write.

Scan Rate - Leave this parameter at the default value of 100 milliseconds. This represents an
optimized system in which KEPServer will poll data from the PointScan modules as fast as possible

and DASYLab can be used to control which data points are processed and which data points are

thrown away.

Note: It is possible to apply scaling to your data from within DASYLab using DASYLab’s own scaling

module. If you prefer to perform this operation in DASYLab you can disregard the settings under

the scaling tab in KEPServer.

Tag Properties, Scaling Tab

An example of scaling for a thermocouple.

PointScan Road Map

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