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There's More to It Than "JUST" Changing BrushesForward from the booklet by Ivan Frank, E.T. To request a copy of this booklet please use our RPI Technical Assistance Request Form or RPI Suggestion and Comment Form. An RPI |
| There is a lot more to it! Modern centrifuges and power tools utilize high torque, high speed motors demanding quick acceleration, fast dynamic braking, electronic speed control and are most always used at the maximum designed speed which promotes maximum wear. Usually by the time someone decides the brushes "just" need changing, excessive damage has already occurred and a simple brush change is not the most advantageous thing to do. Even machines with brush change indicators have no device to tell how many changes have occurred previously or the condition of the associated parts. Yes, the new brushes made it run, but for how long? What else could you have done this time to insure economy, longevity, customer satisfaction and earn an honest profit? Apparently most electronics courses concentrate on circuits that entertain display faces and skip over the electromechanical devices that perform work. As a result, few electronics technicians, BMETs, mechanics or repair types were/are taught the principles of troubleshooting and repair of electronic motors or generators. Many regard the repair of motors as a dirty, degrading and ho hum chore and are unaware of the subtleties even after much need and exposure. Many motors are considered expendable or irreparable; manufacturers do not offer repair parts, even for the large expensive units for several reasons. First, many motors are designed and built with close tolerance - parts are not easily interchanged and must be hand or machine fitted. Second, field service personnel do not have training or facilities to effect proper repairs. Third, hourly charges and location logistics necessitate a one-time service call. Fourth, some small replacement motors are economical and some customers are leery of rebuilt motors, since their previous experience with them was not satisfactory. The rising cost of new motors and the sophistication of electronic controls require multi-talented service technicians to sell and perform competent repairs that provide an acceptable, economical and profitable alternative. Although machine shop practice, electric motor theory, application, rewinding and commutator replacement is beyond the scope of this text, a modest investment in special tools and the careful study of this guide will fill a void and provide a means to help insure that your efforts have quality results. © 2001 Ivan Frank To request a copy of the booklet There's More to It Than "JUST" Changing Brushes please use our RPI Technical Assistance Request Form or RPI Suggestion and Comment Form. |
