The Desco Digital Static Field Meter indicates surface voltage and polarity on objects. The meter can measure ranges of 0 to ±1.999 kV or 0 to ±19.99 kV at a distance of 1 inch with an accuracy of ±5% of the displayed value. The automatic zero button allows adjustment to zero with no screws or dials to turn. The hold button allows the user to “freeze” a displayed measurement for evaluation. A LED range finder helps the operator to place the meter at the correct distance from the surface being measured. The meter will automatically turn off after 20 minutes to conserve battery power (9V).

The Digital Static Field Meter is calibrated with accepted procedures and standards traceable to the National Institute of Standards and Technology.

Features and Components

Making a measurement

Place the meter 1 inch from the object to be measured. This distance is measured from the front edge of the meter case to the surface of the object. The meter now displays a reading (from 0 to ±.200 or ±2.00) of the electrostatic field in kilovolts per inch.

Note: The red ranging lights are provided to help place the meter at the correct distance from the object. The lights are set to produce a concentric red bullseye pattern on a flat opaque surface 1 inch from the front edge of the meter. This can be practiced by aiming the meter at a sheet of white paper.

The display will indicate “1” or “-1” when the meter is over-ranged. Change the range of the unit if necessary. If the measurement exceeds 20 kV, move the meter farther away from the object and multiply the reading by the distance (in inches) away from the object being measured. The measurement accuracy is dependent on a stable ground reference and the 1 inch measuring distance. It is also dependent on the “aspect ratio”, relating the size of the object to be measured to the measurement distance.

Holding the last reading

With the meter positioned 1 inch from the object being measured, press the HOLD button. This will freeze the reading from the object on the display and the analog output signal. This feature allows the operator to move the meter where it may be more easily read or saved for later reference.

Note: The red ranging lights will be off while the meter is in HOLD mode. It is advised to do this between measurements to prolong battery life.

Analog output

The analog output jack labeled “OUT” on the face of the meter accepts a standard 2.5 mm monaural phone plug and is provided so the output of the Digital Static Field Meter may be connected to an oscilloscope, strip chart recorder, external meter or other device. The voltage at this output is 1/1000th (±2 kV range) or 1/10,000 (±20 kV range) of the measured voltage.

Optional upgrade kit with charger and conductive plate

DESCO also offers the optional 19440 upgrade kit (charger and isolated plate) for measuring offset voltage (balance) and charge decay of ionization equipment. The charger is used to place a ±1000V charge on the conductive plate, making it possible to also measure the discharge times of air ionization equipment per ANSI/ESD SP3.3 Periodic Verification of Air Ionizers.