3M 790 Static Monitor

The new 3M 790 Static Monitor is designed to continuously monitor the voltage level on one or two operators using a high impedance voltage measurement circuit. The measured operator's voltage is compared to one of four user selectable (1V, 3V, 6V, & 9V) internal reference voltages. An alarm will sound with a corresponding red flashing lamps, when an operators static voltage level exceeds the selected voltage limit. In addition, a wristband contact detection circuit is also employed to let the user know if the wristband is being worn incorrectly or if there has been a loss of continuity in the wrist cord.
The ground cord connection of the 3M 790 monitor is continuously monitored through a low DC current-loop measurement circuit. The ground connection of an equipment chassis can also be monitored by connecting it in series with the monitors ground measurement circuit. An alarm will sound with corresponding red lamps, when this resistance exceeds 10 Ohms.