Technologies inside: Motor controls for artisan cheese maker
Old World cheese recipe used by Shep Ysselstein, owner and “grand fromage” of Gunn’s Hill Cheese in Woodstock, Ontario, Canada, is a New World reality thanks to a secret ingredient: Danfoss VLT variable frequency drives. Throughout the cheese-making operation, the drives provide pumping and mixing capabilities.
Ben Kungl of Oxford Energy Solutions said about 15 VLT drives are used in the plant. Kungl improved efficiency and process control with Danfoss VLT drives in three areas: fluid pumps, ventilation system, and cooling compressor. Three Danfoss VLT Micro Drives control pumps used to off-load milk from the truck into the raw tank, transfer milk into vats, and for washing. Kungl applied a VLT drive to control the hoist motor that lifts cheese trays from the brine. Another Danfoss VLT Micro Drive is used for ventilation.
Kungl also applied a Danfoss VLT AutomationDrive FC 302 in a NEMA 12 enclosure to modulate the compressor in the outdoor chiller. The drive serves a dual purpose: to save cost by requiring up to 50% less energy than a system that does not use a VFD, and give the customer a wide range of adaptability. The FC 302 drive controls the scroll compressor speed and capacity, while two more VLT Micro Drives control the Zeihl-Abegg condenser fan motors for a fully modulating system.
Kungl said, “The VLT industrial drive family has an outstanding history of reliability in our company. They have a large dc bus that gives them a very large voltage tolerance.”
Danfoss VLT drives are built in the U.S.A., in Milwaukee, Wis. “Unlike other variable frequency drives, these units use algorithms dedicated for flow applications. That simplifies implementation. There are a lot of built-in features, from process PI controller to a Smart Logic Controller, that often make a PLC unnecessary. Plus, they can handle up to 122 F ambient temperatures (50 C) without derating, so no special ventilation is needed,” he said.
For a general all-around dairy operation like this one, the efficiency (50% reduction in energy use) of variable frequency drives give Gunn’s Hill Artisan Cheese “all the flavors of pump and motion control they need,” Kungl said.
Ysselstein said that without the drives, “I wouldn’t be making good cheese.”
For more application details and photos, see: Artisan cheese maker shares secret technology ingredient.
– Patrick Appleby is vice president sales – industry, Danfoss. Edited by Mark T. Hoske, content manager CFE Media, Control Engineering and Plant Engineering, email@example.com.