DGT by Senmatic – Start Tray/Drain Tray

Senmatic’s Start Tray / Drain Tray system is an intelligent irrigation system which lets plant evaporation-rate dictate the rate of water addition. The start tray and the drain tray are used to control the irrigation of cultures grown in rockwool or perlite, for example tomatoes, cucumbers and other plants.

How the start tray works:

Rockwool slabs with plants are placed on the start tray. It is important that the plastic foil is removed from the bot- tom of the Rockwool slab. If perlite is used, holes are cut in the bottom of the bags, so that the excess water can run off. During irrigation, part of the fertilizing water will remain in the Rockwool, and part of it will seep into the reservoir of the tray. The reservoir of the tray is connected to a sensor. The sensor gives a signal for irrigation when part of the water in the reservoir has been consumed by the plants placed on the start tray. The quantity of water to be used can be adjusted by lifting or lowering the sensor electrode. The electrode is connected to an irrigation device which starts the irrigation when the electrode has given a start signal.

How the drain tray works:

The drain tray works in the same way as the start tray. The drainage performed during irrigation is measured by a drain counter, which is connected to the tray. Unlike the start tray, the drain tray cannot perform an irrigation itself. The drain tray has to be connected to a fertilizer mixer with a program controlling the drainage. Control of the desired drainage percentage is performed by adjusting light quantity on the sun-integrator so that the pause between the irrigations is changed dependent on the deviation between actual and desired drainage percentage. The drainage percentage is to be adjusted in the program. Control of the drainage quantity saves water, and at the same time ensures that surplus nutrients and root exudates are not accumulated in the slabs.

To use the drain tray program it connected to an AMI Penta Fertilizer Mixer. Drainage from the drain tray must not exceed 300 ml/min.

It is also possible to incorporate monitoring and data-management into this system by connecting a PC with the SuperLink program installed. With the PC program, there are several possibilities to change the setpoints and collect the data.

Standard lengths of the start tray/drain tray are 200 cm and 240 cm, but special lengths can also be delivered on request

 

Suitability:

• Controlled environment agriculture (CEA) facilities
• Commercial grow operations
• Greenhouses and nurseries
• Vertical farming
• Indoor farming
• Urban farming
• Grow-rooms

 

Features:

• Irrigation control of cultures grown in rockwool or perlite
• Exact dosing of water and fertiliser