- Customer
- Daiwa Computer Co., Ltd.
- Industry
- Agriculture
- Contec products
- CONPROSYS PAC Series
- Goals
- Quality improvement, Work efficiency improvement
Software company Daiwa Computer automated hydroponic melon growing with Contec’s CONPROSYS PAC controllers, raising annual harvests from four to five and production by 25%.
Overview
Daiwa Computer Co., Ltd. develops business software and integrates systems. Under its “i-Nogyo” initiative it applies ICT to farming to address Japan’s shortage of farm successors, pass down farming know-how and improve food safety, digitizing craftsmanship that once relied on intuition and experience.
The company began collecting agricultural data in August 2008 and started melon cultivation in Fukuroi City, Shizuoka, in February 2009. It now grows melons and tomatoes hydroponically with local producers, the city, Shizuoka University and Keio University, has built farm management, environmental control and RFID traceability systems, and researches artificial-light plant factories with Osaka Prefecture University.
Challenge
In melon hydroponics, rock wool replaces soil and nutrient solution is supplied automatically according to sunlight, so watering rises from about twice a day to 20 to 60 times. Daiwa’s first in-house microcomputer irrigation system suffered rust from moisture and reliability problems, so it needed a commercial, open system, along with in-house atmospheric data to justify the investment.
Solution

Division Manager Tashiro found the CONPROSYS PAC Series at an exhibition and adopted it quickly. It controls batch nutrient feeding in a glass house with a large south-facing roof, and progress can be monitored remotely. Tashiro found the PAC Series with CODESYS “easy to understand and use,” and it supports global programming and communication standards without depending on specific manufacturers.

Next, the company plans to monitor temperature, humidity, CO2, rainfall and nutrient EC to control irrigation, skylights and boiler temperature automatically, and to grow more melons by reducing spacing between pots while keeping the one-fruit-per-plant method.
Results
Automating skilled work preserves know-how as data and supports quality for a well-known local brand. Annual melon harvests rose from four to five, production increased 25%, and the PAC Series now runs in five greenhouses. Daiwa plans to analyze sensing data in the cloud to further optimize cultivation.
Contec products used
Originally published by Contec Co., Ltd. at contec.com.
