Daniel Woodhead, Inc.

Roy E Caruthers

A ground continuity monitor for a tool stop controller includes a pair of resistive conductors connected in series between the power line hot and neutral leads. At the junction therebetween they are connected to the ground lead and to a controllable shunt. The resistive conductors maintain a sufficient voltage at the junction to hold the shunt in a conducting state until the junction is connected to ground through a low impedance, preferably less than substantially 100 ohms. An indicator, such as a lamp, indicates the state of conduction of the shunt, thereby providing the tool operator with an indication of the actual electrical continuity of the ground path from the tool ground lead back to ground at the power line source. In the event of a ground fault, no high voltage is imposed by the monitor on the tool case.

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Bay City, TX, United States of America

Roy E Caruthers