NIOSHTIC-2 Publications Search
Design Modification of Femco Model 702909 Wireless Ground Monitor.
Vitt LP; Ritter DT
NTIS: PB/262-858 Available for Reference At Bureau Libraries :31 pages
This report details the work done to provide the Bureau of Mines with a customized wireless ground monitor system. Femco model 702909 wireless ground monitor was modified as follows: (1) a voltage regulator was added to prevent false trips with line voltage variations, (2) a ground wire trap was designed to eliminate problems with parallel paths and provide spark suppression, (3) a three-phase filter was designed to permit complete test of installed systems, and (4) the design was modified to insure trip with an open ground wire in the event of a failure of any one semiconductor component.
CP; Final Contract Report;
NTIS Accession No.
NTIS: PB/262-858 Available for Reference At Bureau Libraries
Femco Div., Gulton Ind., Inc.
Page last reviewed: October 29, 2021
Content source: National Institute for Occupational Safety and Health Education and Information Division