Since the Seven Hills Vineyard complex was a new installation, the customer wanted to design all elements, including the irrigation system, with the appropriate flexibility and capacity in mind for future development. To ensure the irrigation system could provide proper flow and pressure from the initial installation and beyond, it was determined that all pumps should be controlled utilizing variable speed technology. Besides providing the maximum system flexibility, utilizing VFDs would increase system efficiency and reliability while returning energy savings. In addition, the application of drives would allow the system to match water flow and pressure to actual demand at any given time, minimizing water consumption.
Danfoss VLT® AQUA Drive series products were selected for the installation, but there was one hurdle that needed to be overcome: the installation included an 800 HP pump, which was beyond the current cataloged VLT AQUA Drive product range. This situation however coincided perfectly with a product development activity taking place at the Danfoss Drives North American headquarters in Loves Park, Illinois, to expand the product range to 1.2 MW. A coordinated effort between Mitchell Lewis & Staver and Danfoss sales and R&D resulted in allocating one of the early production 800 HP units that were in development. This new power expansion of the VLT series products is modular in design and utilizes technology currently of the 125–600 HP VLT series products by paralleling power sections, resulting in increased power capabilities. The modular 800 HP VLT AQUA Drive was assembled in Danfoss Drives’ Milwaukee facility and was put through the full series of tests and evalutions by Danfoss production and R&D departments before being released to the customer.
At Seven Hills Vineyard, the two main water supply wells consist of one 350 HP Vertical Turbine Pump and one 800 HP Vertical Turbine Pump. The 350 HP pump can deliver water to the east and middle ponds, while the 800 HP pump can deliver water to all three ponds. Both pumps are controlled with Danfoss VLT AQUA Drives. The pond pump stations are all vertical turbine style pumps of various horsepower ratings.
All the pond distribution pumps were supplied with Danfoss Drives and Soft Starters.
The distributor was able to offer a comprehensive integrated pumping system for the customer's unique application. This included Danfoss Drives VLT Series products and pressure transducers, as well as the pumps, motors, level sensors, meters, and other required control equipment. These components were integrated into a central control system which monitors well level, discharge flow and discharge pressure. This total system integration approach, as well as the expertise provided by Danfoss and Mitchell Lewis & Staver in order to implement it, was one of the key selling points on the project.
Seven Hills Vineyards intends to sell the acreage to premier wineries around the country and provide them with turnkey service that includes crop planting, vineyard maintenance, irrigation and harvesting. Buyers are welcome to handle their own cultivation of the acreage if they desire, but would pay a monthly fee for irrigation services, which are owned by Seven Hills Vineyards. The centralized control system and the VLT AQUA Drives provide the flexibility needed to implement this business plan by allowing the system to grow and adapt with the needs of the various wineries it was built to serve.