Patent ID: 8732895
Filing Date: 2014-05-27
Classification: A47L

Abstract:
1. A central vacuum cleaning system comprising: a) a plurality of vacuum sources connected to provide parallel suction forces, each vacuum source comprising a vacuum motor, b) a control circuit, and c) a plurality of switches, each switch associated with a respective one of the vacuum sources, wherein the control circuit is adapted to control the switches, and each switch is adapted to apply electrical power to its associated vacuum source in accordance with control from the control circuit, and wherein the control circuit is connected independently to each switch and configured to control each switch independently to apply a soft start function in which the application of electrical power to the plurality of vacuum sources is coordinated to limit instantaneous total inrush current of the vacuum sources by a combination of applying power to the vacuum sources one after the other and ramping up power applied to multiple vacuum sources during startup.