Task

Vegetables are reaching us in several ways. Some vegetables are imported from around the world and others are grown in the Netherlands. If we look at the range of fresh products at the greengrocer, at the local market or at the supermarkets, there is a wide choice. An interesting process is involved in the preparation of leafy vegetables, tuberous plants, cabbages, onions and sprouts.

From seeding to harvesting

The Dutch seed breeding industry is improving continuously to enable the growth and harvest the vegetables. The company Bejo Zaden in Warmerhuizen, the Netherlands, with subsidiaries in more than thirty countries, is a leader in breeding, production and trading vegetable seeds. A lot of research is required for seed breeding and Bejo uses, test climate chambers for this purpose. In these test chambers the influence of, for example, temperature, humidity and lighting on the development of seed is examined.

9-compartment chamber

Frost Klimaattechniek, based in Stompetoren is specialized in the supply and installation of climate chambers. Special for Bejo, the company has joined forces with JUMO.
In the Netherlands, efficiency is key in seed breeding. Therefore it is important to monitor all factors that may influence the growth of seeds and to be able to adjust them if necessary. For this process Bejo has climate chambers at its disposal for testing purposes. One of these chambers is the 9-compartment chamber. For this purpose, Bejo started looking for a replacement. Frost Klimaattechniek has been asked to take the design of the old chamber as a basis for the new one.

The design and implementation ensure the highest reliability of the system for anticipating within the future.

Solution approach

Ready for the future

Specific knowledge is required to control the new test climate chamber with 9 compartments. Temperature and humidity were measured in the current chamber, therefore this will also be the basis of the new chamber. Furthermore, the new chamber must be equipped with expansion possibilities for expectetations of the new applications.
In particular, it will be possible to lower the desired lower limit of temperature. To rotate the seed, each compartment is equipped with a roller bank. Bejo's request is a possibility to make use of one central control system, which has been realised in the form of a PLC control with an intuitively operated HMI. In terms of lighting, Bejo requested LED modules in the various compartments instead of the standard fixtures.

JUMO PLC-technic

PLC technology in combination with control technology requires specialist knowledge and skills. Years of experience in this industry have ensured that Frost asked JUMO to control the new 9-chamber climate cabinet at Bejo.Temperature, humidity and lighting are controlled per compartment. The intention is that these quantities can be set arbitrarily per compartment, without causing condensation problems. In any compartment the set temperature gradient should thus be achievable both positively and negatively.
In addition to heating, cooling, humidifying and drying individually, the JUMO mTRON T regulates and controls the ventilation speed and controls the rollers and light intensity per compartment.

Project outcome

The co-operation of Frost with JUMO has resulted in an installation at Bejo that meets all relevant refrigeration and electrical requirements. The design and elaboration provide for the highest installation reliability while anticipating the future. The cabinet is ready for the installation of a double compressor. The focus is on reliability, accuracy and ease of operation. This contributes to research that provides more insight into the physiological aspects of Bejo's seeds, which can lead to yield increases, yield security and improved product quality.