High-Sensitvity,DC stable electrostatic voltmeter

  • Product No:370
  • Manufacturer:Trek, Inc.

The Trek Model 370 is a precision electrostatic voltmeter with the unique capability of making noncontacting surface voltage measurements in the range of 0 to ±3 kV DC or peak AC.

The 370 employs an electrostatic field-nulling technique which achieves high DC stability and high measurement accuracy even if the probe to measured surface spacing changes. This permits measurements of either stationary or moving surfaces without the need to establish fixed spacing to maintain accuracy.

An automatic gain control feature of the 370 eliminates the need for manual adjustment when changing probes or when changing the probe to measured surface separation.

The 370 also features one-step, push-button zeroing. When the ZERO button on the front panel is pressed, the 370 automatically adjusts the output to zero volts when the probe is coupled to a known zero volt surface.

A precision voltage monitor provides a low-voltage replica of the measured electrostatic voltage for external monitoring purposes, or for use as a feedback signal in a closed-loop system.

An optional data acquisition module is available, featuring an IEEE-488 compatible interface, 14-bit resolution, 12-bit accuracy, and a programmable sampling period from 10 ms to 30 minutes.

The 370 can be operated on a bench top or, with optional hardware, in a standard 19-inch rack.

Very High Speed of Response: Less than 50 ms for a 1 kV step

Measurement Range: 0 to ±3 kV DC or Peak AC

Measurement Accuracy: Better Than 0.05% of Full Scale

Automatic Gain Control (eliminates manual adjustment)

One Step, Push- Button Zeroing 

Precision Voltage Monitor Output

Optional Data Acquisition Module (with an IEEE-488 compatible interface)

CE Compliant


  • Measurement Range: 0 to ±3 kV DC or peak AC

  • Measurement Accuracy

    At the Voltage Monitor: Better than ±0.05% of full scale

    At the Voltage Display: Better than ±0.1% of full scale ±1 count, referred to the voltage monitor    

  • Speed of Response (10% to 90%): Less than 50us for 1kV step

  • Stability

    Drift with Time: Less than 150 ppm/hour,noncumulative.

    Drift with Temperature: Less than 100 ppm/°C

  • Probe-to-Surface Separation: 2 mm ± 1 mm (recommended)

  • Dimensions:108 mm H x 223 mm W x 430 mm D(4.25" H x 8.75" W x 17" D)

  • Weight:5 kg (11 lb)