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Wrist Strap Monitoring
Principle of Operation
The 3M WS Aware Workstation Monitor works with dual wrist straps of almost any type that have a
standard 3.5 mm audio mono plug. The WS Aware monitor verifies proper wearing of a wrist strap by
measuring an operator’s resistance. For this, the WS Aware monitor provides a signal to the wrist strap.
This signal is extremely small (in the order of ~25 millivolts Maximum) and doesn’t cause any problems to
components or to personnel.
A charge can be easily developed on a body during movements. Though such a charge is quickly
drained when an operator is properly grounded, significant voltage may be present on an operator during
movements. The WS Aware monitor detects this voltage and if it exceeds the preset level, indicates body
voltage presence.
Alarm thresholds for body resistance and body voltage are set at the factory but can be changed in the
field. Please contact us or our authorized distributors for details.