According to the company there are many benefits in the use of AC over direct current, a technology that is quickly becoming an old standard.

For example, company officials said, the performance level on an AC unit remains high even as its battery power drains.

“Until the battery hits 80 per cent discharge, performance is said to remain at 100 per cent, which is beyond the capacity of DC power,” the company said.

Braking is another difference, as it is accomplished by the combination of electrical regeneration and the application of a standard mechanical brake.

Because the carrier is AC, no brushes, spring sets or commutators are required. The vehicles, in fact, only have a stator and a rotor.

They are also more energy efficient, up to 10% in operation than a DC motor.

“AC motors draw fewer amps, so the batteries last longer,” the company said.

Lastly, the control and the feel of the unit are better than its older counterpart as the controllers are more sophisticated, Damascus said.

The company has made AC power available on its LMA3 and LMA4 two-passenger 48-volt Lil’ MAC, its new MAC-4 48-volt four passenger that features a heavy-duty rear axle, and the new MAC-8-AC 72-volt that seats 8-12 passengers and has enclosed wet brakes.

While the AC line is fueling the company’s growth, it said that its reputation in the industry for reliability in mining and utility vehicles is just as important. While the company started out as a supplier of rock-dusting units for underground mines, it now is known for runabouts, light transporters and diesel and battery-powered personnel carriers.

The company has seen one significant change lately – a now-retired Walter Stewart has been replaced by new president Eric Miller – but the company’s theory of developing products based on customer feedback will not change.

“The growth of our product line was never haphazard. It was based upon a deliberate series of innovations and improvements.

“The principles of ‘human engineering’ are applied to ensure operator comfort and safety,” Miller said. “A safe worker lives better; a comfortable miner works better.”

Published in the August 2008 Coal USA Magazine