Software Packages

• Visual Basic
• Microsoft Access
• KEPware KEPServerEx
• National Instruments
• Measurement Studio

This remote panel monitoring system was designed to allow users to remotely monitor and log data from remote facilities via dial up modem connection. This system allows for monitoring of up to six different interrelated refrigeration units on one modem connection. This system allows monitoring and control of several system statuses and supports a history logging of several different temperature values for trending purposes.

A Visual Basic application was written to provide the user interface. A connection is established in Visual Basic by calling KEPServerEx OPC, which establishes communication to the PLC via modem or serial port. Once a connection is established monitoring of temperatures and other system variables is possible. It is also possible to download history logging from the PLC and view this information as a graph or in a spreadsheet. Various controls are also available; such as clearing alarms and changing refrigeration settings.

Hardware Basis

• Intel PC
• Modem
• Direct Logic 205

Communications

• VB to OPC
• OPC to PLC via modem dial up connection
• OPC to PLC via RS232 serial connection