Project Overview

A total of three seed corn facilities were automated using similar control systems. The plants dry harvested seed corn, shell the seed corn, store the corn in bulk towers and condition/bag the corn for sale. Dahlen Systems, Inc. primary role included the design and purchase of the controls and SCADA system, the creation of a process narrative, programming the control system, programming the SCADA system, programming the SQL database, creating reports, plant checkout, start-up and operator training.

The SCADA system is used to monitor and control the drying, shelling, storage, conditioning and bagging operations. Temperature, drying times, motor control and seed moisture are all functions of the system. Process information (temperature, pressures etc.) is logged using redundant Wonderware InSQL servers. Batch information is stored in a Microsoft SQL database.

The primary concern of the plants was to keep different seeds separate. The SCADA system prevents accidental mixing of seed by tracking the seed from the moment it is off-loaded from a truck to the bulk storage.

Project Costs

Engineering and materials $500K

Controls

Multiple Allen-Bradley SLC 500 and PLC 5 processors

	Remote I/O on DeviceNet
	150 analog points
	200 discrete points

Wonderware InTouch SCADA system

	7500 tags
	15 main screens showing a graphical representation of the process
	Several pop-up screens for common control of different equipment, i.e. motors.
	Fiber Optic DH+ network to the controllers
	DH+ Fiber Optic network installed in a “ring” configuration to allow redundant paths to the controllers
	Fiber Ethernet network for the computers
	Real time and Historical data logging using InSQL logging
	Additional data logging to Microsoft SQL of warehousing summary information
	3 View and control nodes
	Redundant tag servers
	Redundant SQL servers with auto fail over
	Reports created in Seagate Crystal Reports

Data is transferred automatically from the corporate SAP system and imported into the Microsoft SQL database.