Subsequent to the launch of the new VDrivePlus and AlphaDrive-Micro variable-speed drives (VSDs) from Hudaco Group company Varispeed, bearings and accessories distributor Bearings International (BI) has embarked on a training and sample-distribution campaign at its 50 BI branches in South Africa.

Two training sessions have been conducted at BI’s head office in Boksburg, Gauteng, with a further two scheduled in Cape Town and Durban before the end of this month. Brochures are also handed out during the campaign.

“Notably, the Varispeed VSDs are optimally suited to the harsh conditions – such as dust, precipitation, high-temperature variations, high altitude and weak network conditions – prevalent in South Africa’s mines,” says BI offer marketing manager Victor Strobel.

The VDrivePlus ranges from 0.4 kW to 400 kW, available in 240 V and 400 V. The VSD features advanced motor control based on digital signal processing technology, together with smart auto-tuning. Additional features include flexible inverter control, dual high-resolution analogue inputs and free mappable input/output channels.

A universal function set is available for a range of industrial and residential applications, including integrated proportional-integral-derivative or pump-controller routines. Smart personal computer tools allow for quick inverter control, parameterisation and troubleshooting.

The compact AlphaDrive-Micro VSD ranges from 0.2 kW to 5.5 kW and is available in 240 V and 400 V. It is easy to integrate into an electrical panel, as it mounts directly onto a DIN rail. A built-in software menu caters for optimised parameters for basic functions and applications such as fans, belts, conveyors and pumps.

Together with the VDrivePlus, these VSDs offer the best performance-to-cost ratio on the market, without compromising on quality and reliability, says Strobel.

“Owing to the current economic environment, the market is very price sensitive and, therefore, any energy efficiencies or cost-savings we are able to offer are hugely beneficial.”

Mining-process equipment that does not operate effectively in demanding conditions can have a significant impact on production output, especially considering that minerals processing is generally very energy intensive.

“It has been reported that energy consumption can account for up to 30% of a mining operation’s running costs, mainly for electric motors,” alleges Strobel.

He adds that these are normally operated at fixed speeds, which is said to be the easiest means of control. However, a significant amount of energy is squandered as a result, as this approach ignores the actual output requirement.

Actual energy consumption can be reduced by as much as 60% using VSDs to control motors. The VSDs can also be used in applications such as lifting, crushing and reticulation at mines.

Strobel enthuses that VSDs also save costs associated with the machinery that is being driven by the motor. Starting a motor “direct-on-line” puts enormous strain on the gearbox or coupling, which, in turn, affects the pump, fan or whatever other equipment is being driven.

BI complements its VSD offer with its range of Bauer Electric motors. These aluminium three-phase 380 V motors suited for various applications carry the main benefit that the motors are far lighter than their cast-iron equivalents, owing to the aluminium casing and end shield.

“We are proud that the VDrivePlus and AlphaDrive-Micro VSDs are being rolled out across BI’s 50-branch countrywide network, and will be launched officially at a media event later this month,” concludes Strobel.