This vacuum interrupter have three terminal vacuum switch module containing both load and pre-insertion contacts operated by a single contact rod. A mechanical adjustment system is provided for the pre-insertion contact which controls its range of motion and allows it to be positioned so that the pre-insertion contacts may engage at a set interval before the load contacts engage. This also allows the pre-insertion contacts to break at a set interval after the load contacts break. This configuration allows the use of an externally mounted pre insertion resistor or inductor to limit the inrush currents and voltage transients associated with single and parallel bank capacitor switching .
This patent would offer significant advantages over
capacitor switches available today. It would provide a reliable method of reducing inrush currents which does not require the use of permanently installed inductors used with standard vacuum switches nor does it require the complex electronic control and separate mechanisms
needed with three phase zero closing switches.
Thanks to Mr. Michael D. Glaser to send some technical documents to me for this post.
