Products > Electrostatic Voltmeters > Non-Contacting

Model P0865 High-Sensitivity, DC Stable ESVM

The Trek Model P0865 is a DC stable, precision electrostatic voltmeter for making noncontacting surface voltage measurements in the range of 0 to ±10 kV DC or peak AC.

Research and industrial applications include charge accumulation monitoring of the LCD production processes, monitoring surface potentials in the electrostatic painting process, research and development in the electrophotographic process, and measuring electrostatic potentials on polymers, rubber, fabrics, and paper.

The Model P0865 employs a field-nulling technique for noncontacting voltage measurement that achieves DC stability and high accuracy even if the probe-to-surface spacing changes. This permits measurements of either stationary or moving surfaces without the need to establish fixed spacing to maintain accuracy.

The Model P0865 patented probe design eliminates the need for close tolerance components. This significantly improves noise and drift performance, both in the presence of contaminating particulates and under conditions of high humidity and wide temperature ranges.

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

The Model 3450 probe assembly includes a sensitive electrode and preamplifier, which is driven to the same potential as the measured value to eliminate arcing there between. A three (3) meter cable permits remote probe positioning. The Model P0865 can be operated on a bench top or, with optional hardware, in a standard 19-inch rack.

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Measurement Range
0 to ±10 kV DC or peak AC.

Better than ±0.1% of full scale
as referred to the voltage monitor).

Speed of Response 
(10% to 90%) 

Less than 200 µs for a 1 kV step change.
Less than 5 ms for a 10 kV step change. 

Full Signal Bandwidth 
DC to better than 50 Hz.

Drift with Time

Less than 100 ppm/hour, noncumulative.
Drift with Temperature
Less than 200 ppm/°C.


High-Voltage Ready LED
A LED indicator illuminates when the Model P0865 electrostatic voltmeter is ready to make high-voltage measurements.

High-Voltage ON/OFF
A two-position toggle switch that turns on and off the high voltage supply inside the instrument. 

Zero Adjust
A ten-turn control to null offsets or other zero errors which occur within the system.

Voltage Monitor Output
A buffered output providing a replica of the measured voltage.
1/1000th of the measured voltage.
Output Noise
Less than 20 mV rms (measured using the true rms feature of the Hewlett Packard Model 34401A digital multimeter).
Output Impedance
Less than 0.1 Ω.

Voltage Display
4 1/2 digit LED display.
0 to ±10,000 V.
1 V.

Zero Offset
Less than ±2 counts, referred to the voltage monitor.
Sampling Rate
Three (3) readings per second.

Power On/Off 
A two-position rocker switch that turns on and off the main power.

High Temperature Probes 
(up to 100 °C)
Model 3455ET (end-viewing).
Aperture Size 

1.52 mm diameter.
Model 3453ST (side-viewing).
Aperture Size 

3.05 mm x 1.52 mm.

Probe Body Type

11.8 mm H x 11.1 mm W x 76 mm L
(0.5" H x 0.4" W x 3" L).

Probe Cable Length
3048 mm ±76 mm (10 ft. ±3 in.).


Accessories Supplied

  • Operator’s manual and line cord.


  • Model 3450EC Probe Extension Cable 
    (from Model P0865 to Probe) (p/n17218) 

    Model 3460-1 Line Driver (p/n 17181)

    Full-Rack Mounting Kit 607RA Rack Mount Kit (19-inch) (p/n C4062)


Probe holder assembly (not supplied) should be of a non-dissipative material with insulating properties.

Recommended Probe-to-Surface Separation
3 mm ±1 mm.

Standard Resolution Probe
Model 3450 (side viewing).
Aperture Size 
3.05 mm x 1.52 mm.


Power Requirements
Line Supply 

Factory set for one of two ranges:
90 to 127 V AC or 180 to 250 V AC, at 48 to 63 Hz
(specify when ordering). 

Operating Conditions

0°C to 40°C.
Relative Humidity
To 90%, noncondensing.

134 mm H x 432 mm W x 432 mm L
(5.25" H x 17"  W x 17" L).

15 kg (33 lb).

Voltage Monitor Connector
BNC connector.

Ground Receptacle
Binding post.

AC Line Cord Receptacle
Standard three-prong line cord receptacle with an integral fuse holder.


TREK, INC. certifies that each Model P0865 is tested and calibrated to specifications using measurement equipment traceable to the National Institute of Standards and Technology or traceable to consensus standards. A Certificate of Calibration accompanies each instrument when it is shipped from the factory.

Low-Voltage Safety Compliance 
(EN 61010-1)

Overvoltage Category
CAT II: Local-level mains, appliances, portable equipment.
Pollution Category
Degree 1: Operate in environments where no pollution or only dry, nonconductive pollution occurs.

All specifications are subject to change.


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