A non-intrusive system (SMS) to monitor sparking along the brush/commutator interface of a DC machine

DC machines are widely used in industrial purposes due to their precise variable speed control characteristics and large overload capabilities. Quantitative assessment of commutation in DC machine, measured over the complete duty cycle has not been possible. Imperfect commutation usually causes sparking under or at the edge of the brushes. Such sparking can cause damage that is costly in material, labour and downtime. The authors describe the philosophy, principles of operation, hardware and synchronisation of data. They also describe the optical system used to monitor the speed of the machine. These generated signals from the speed monitoring circuit are used to mark the captured data, reference signal for frequency multiplication and speed monitoring are also going to be described