Case Studies

Lochert Brothers Fruit Processing Management System

The purpose of the system is to provide a means of monitoring and managing fruit processing in the packing shed. Fruit is tracked by grower from delivery through to final grading. The system interfaces to Lochert's existing Colour Vision grading/sorting system, collecting and analysing fruit quality and size statistics by grower and feeding the information into the management accounting system.

Client-server architecture

Most large SCADA installations involve a number of full networked PC's installed on the factory floor and these networks are usually based on client-server technology.

An enterprise wide solution has been provided for Lochert Brothers using Windows NT Terminal Server and thin clients and Vision SCADA software.

The thin client model is similar to the traditional mainframe and terminal architecture. It places all the computing power in one server and thin clients are distributed around the network.

Thin clients are inexpensive because they need little computing power and no hard disk drive. System reliability is dramatically improved and upgrades are easily controlled because data resides on a single server and is managed centrally.

The thin client displays the familiar 32-bit Windows GUI on a range of hardware such as DOS based PC's, Windows based terminal devices or personal computers running Windows or Windows NT. Remote dial connections can be made through standard PSTN.

A significant advantage to traditional SCADA systems is that changes are made to the software on the server only. There is no need to upgrade the client's machines and manage individual licenses.

System Overview

The system is designed on an Ethernet network and integrates into the existing management LAN. A Cisco switch is installed for this new network.

Two Servers were installed. One machine is set up as a SQL 7.0 Server and the other is a Windows NT Terminal Server. Windows terminals (thin Ethernet clients) are installed in the factory on both Dos based industrial PC's and Net PC's. The client software is also installed onto existing personal computers connected to the business LAN for access to the factory floor SCADA system. Remote dial in is provided via a notebook. APC also have dial in access to maintain and service the installation.

Special drivers were developed to communicate with the existing Colour Blemish Sorter equipment. Toshiba T2N PLC's are installed on the Ethernet network. SCADA software was developed with VISION 2.0.


  • Bin tracking and inventory management greatly improved
  • Real time reporting and data collection
  • Management information useful, timely and easy to read
  • Streamlined interface of production and grower information into accounting system
  • Full exploitation of statistics available from Colour Vision system
  • The simple but powerful thin client system enables big cost savings in installation and commissioning time and subsequent system maintenance and expansion.