Emsflower currently has around 26 hectares of greenhouse and grows more than 500 million plants every year. Its problem on how to minimize costs in automation system for plant handling and watering was solved by automation provider Riwo Engineering, along with the Control Techniques Drive Center.

Riwo Engineering’s new automation system had to encompass spraying and pest control, watering, autonomous function of individual sections and central control, precise positioning overruns of 250m, the transport of plants, and the means to transport water and power along 150m. This system is easy to use and all at a limited cost.

The system is composed of trolleys with plastic wheels that run on overhead rails along every 8m-wide greenhouse bay. The two wheels placed on each trolley are powered by asynchronous motors with encoders controlled by Control Techniques’ 1,5kW Unidrive SP AC drives.

The modules and trolleys, powered by Unidrive SP drives from Control Techniques, communicate through CT-Net along with the master drive and thence with the master computer. CT-Net enables several drives to be connected into a master, while the onboard programming allows the required degree of repeatability and accuracy to be reached. Its open structure, which is based on the Modbus protocol, provides the master with a low cost interface. Control Techniques’ Unidrive SP is an advanced “solutions platform” AC drive, which is configurable into five operating modes – closed and open loop, vector, regenerating and servo modes – compatible with standard networks that is configurable for all types of AC motors such as linear motors and accepts 14 position feedback protocols.