Design and construction of single phase ac and dc motor speed controllers

This destoning machine was originally supplied with a series wound vacuum cleaner motor which had poor life expectancy and was incredibly loud at 20,000 rpm. We obtained a industrial dust extractor unit and proved we could change the design before purchasing replacement equipment, The new fan was the same cost as 1 replacement vacuum motor, is very quiet and will last many times longer than the 800 hrs the original motor would.

This Upgrade of  lights presented a number of issues, Facing the beach and constant replacement of the lamps. We selected 316 marine grade light fittings with high performance 11 watt  15,000 hr lamps, saving 17 c / hr at current electricity costs.