Many features of the variable-speed drive (VSD) solutions provided by drive technology provider SEW-Eurodrive can be applied to projects in the heating, ventilation and air-conditioning (HVAC) industries, says SEW-Eurodrive mechatronic sales engineer Paul Strzalkowski.

He states that locally VSDs are supplied mainly to pump and fan manufacturers in the HVAC industry.

“We’re making headway in this industry, as consultants working on bigger buildings, such as hospitals, shopping malls and cold rooms, need dedicated HVAC drives, which we can supply with an option of ingress protection (IP) ratings of IP 66, IP 55 or IP 20.”

A higher IP rating for VSDs allow for the drives to be close to a motor in potentially dusty, wet or tough conditions. This also helps to reduce the panel space required. Strzalkowski states that the company’s IP 55 and IP 66 drives can be mounted on a wall, next to, or near, a geared motor unit, while the IP 20 unit fits directly into a panel.

Products such as the company’s MOVITRAC LTP-B Eco range of HVAC VSDs have key features for the HVAC industry, including varying the speed on important components such as pumps and fans, or chilled water flow based on cooling demand. This allows for increased energy efficiency.

The VSDs also allow for simple start-up, with a focus on user friendliness, including a text-based screen to display critical parameters. There is also a Bluetooth option for changing and reading these parameters via a laptop, for which the necessary software is supplied. The system also has a fire mode, which ignores signals and alarms to keep the LTP-B HVAC operating during a fire to ensure smoke extraction from buildings.

The system also has an energy optimisation mode bypass control and is designed for maximum motor control efficiency.

Frozen Food Packaging System

SEW-Eurodrive recently supplied 64 MOVIGEAR geared servomotors to food and beverage machinery manufacturer and supplier HG Molenaar for the conveyor system of a frozen fish and vegetable packing company in Germany. This resulted in a massive energy-saving for the overall plant, Strzalkowski claims.

He adds that this involvement can be used as a significant “selling point” in the food and beverage industry, particularly those that use freezing temperatures for storage.

“We’re already selling MOVIGEAR to the local market. Breweries and bottling companies are using it, as well as some smaller cooling plants. It is generally well accepted in South Africa, especially owing to cost-saving factors such as the reduction in cabling, ease of installation, and energy saving,” he states.

SEW-Eurodrive supplied these motors from its branch in Cape Town to the Paarl-based original-equipment manufacturer. HG Molenaar then used these motors and built a weighing conveyor system for one of the three production plants of the Germany-based company.

Strzalkowski explains that the MOVIGEAR system was ideal for this application, owing to its 200:1 speed range, compared with standard VSD speed ranges of 5:1 or 10:1.

“With this result, you don’t need to have different gearboxes or different gearbox ratios for different speed ranges. Instead of having five different speed-range gearboxes in a plant, one can cover most of the ranges with a single gearbox,” he points out.

Further, the MOVIGEAR system comprises crucial components required for use in a wide temperature range from –25ºC to 25º.

All the screws, including the mounting screws for the cover of the drive, as well as the outward shaft, are made out of stainless steel. Nitrile rubber oil seals have used in this application because of their wide operating temperature range from –30ºC to 100ºC, while factory-installed pressure mounting fitting for the electronics and gearbox ensures that any air in the system is purged through a one-way valve.

The Movigear units are designed to be ideal for the strict hygiene requirements of the food and beverage industry.