Model GAM-10
Personal Grounding Monitor

Ideal for Field Service Use

Features:

• Battery Powered
• Belt Worn
• Verifies Connection to Earth Ground
• Audible and Visual Warnings
• Low Battery Warning
• NIST Traceable Limits

The GAM-10 continuously monitors the integrity of a persons' connection to ground, or to a low impedance.  This low impedance is typically a large capacitance to ground and is referred to as virtual ground. Any charge present is shared in proportion to the capacitance of the person and that of the virtual ground. The person can weigh less than 100 pounds or as much as several hundred pounds without affecting the monitor's performance and without requiring any adjustments.

The monitor can be worn like a beeper. It has a stainless steel belt clip. The coil cord is plugged into the unit's Wrist Strap jack and snapped on to a wrist strap or ESD smock.  The virtual ground snap is for the lead wire that connects the unit to a virtual ground.

Operation

Inserting a banana plug into the Wrist Strap jack activates the monitor and initiates a self-test and battery check. If battery voltage is low, the audio alarm beeps.
However, if the higher or lower resistance limit is exceeded or the wrist strap is not attached and/or the virtual ground snap is not connected to the frame, rack or chassis being worked on the LED flashes and the audio alarm beeps. If the wearer becomes disconnected from virtual ground thereafter, the monitor alarms until the wearer reconnects. When the banana plug is withdrawn from the Wrist Strap jack the LED flashes and the audio alarm beeps several times to indicate power off.

Earth Ground Verification

To determine if the virtual ground is earth ground, connect a wire from the monitor's Test Jack to a known path to earth ground, e.g., a water pipe or the third hole in a tested AC outlet. If the virtual ground is connected to earth ground, the monitor's audio alarm sounds continuously.

Calibration

Circuitry is similar to MultiMonitor and GAM Series monitors, hence periodic recalibration is unnecessary. Calibration can be verified with the Model CVU-7 Calibration Verification Unit. The high limit can be confirmed by connecting an appropriate discrete resistor between the Wrist Strap and Virtual Ground Snap.

Certificate of Conformance

A Certificate of Conformance traceable to the National Institute ofStandards and Technology (NIST) and confirming that the instrument meets published specifications is available with all new equipment upon request at no charge.