3M Static Monitor 790 Manual del usuario - Página 4

Navegue en línea o descargue pdf Manual del usuario para Instrumentos de medida 3M Static Monitor 790. 3M Static Monitor 790 19 páginas.

AC Adapter

Figure 1 - 3M

Static Monitor 790

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1.0 Theory of Operation

The 3M

Static Monitor 790 is designed to continuously monitor the voltage

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level on an operator(s) using a high impedance voltage measurement circuit.

The measured operator's voltage is compared to one of four user selectable

(1V, 3V, 6V and 9V) internal reference voltages. An alarm will sound with a

corresponding red flashing lamp(s), when an operator's voltage level (caused by

static generation) exceeds the selected internal reference voltage.* In addition,

a wrist band contact detection circuit is also employed to let the user know if

the wrist band is being worn improperly or has experienced a loss of continuity

between the ground cord and wrist band.

The ground connection of the Static Monitor 790 is continuously monitored

through a low DC current-loop measurement circuit. The ground connection of

an equipment chassis can also be monitored when connected in series with the

monitor's ground measurement circuit. An alarm will sound with corresponding

red lamps, when this loop resistance exceeds 10Ω.**

If all monitored components are operating within the selected operating

parameters of the Static Monitor 790, a green lamp will illuminate.

The Static Monitor 790 uses a modified version of the 3M

Wrist Band (VM Series) and the standard 3M

(see Accessories Section).

*Voltage alarm levels ±15%

**Ground disconnect ±20%

***Ordered separately

Mounting Plate

Static Monitor 790

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Dual Conductor

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Dual Conductor Grounding Cord

Chassis/Ground

Cords with Two-

Wire Connector