Model 520 Series
Hand-Held Electrostatic Voltmeters
Accurately measures surface voltage at a wide range of spacings
No need to maintain a fixed spacing
Inspect small spots for charge accumulation
Measure charge accumulation in difficult-to-reach locations
Chopper stabilized for drift-free operation in ionized environments
Low cost
Model 520
Over a spacing range of 5 mm to 25 mm, the 520 voltmeter provides better than a 5% voltage
measurement accuracy, while the typical fieldmeter provides a voltage measurement error
in excess of 50%. An optional voltage monitor output is available.
General Specifications
All Model 520 specifications are with a probe-to-surface separation of 15 mm, +/-10 mm.
All Model 523 specifications are with a probe-to-surface separation of 45 mm, +/-15 mm.
Performance	Model 520	Model 523
Measurement Range	0 to +/-2 kV DC.	0 to +/-20 kV DC.
Accuracy	Better than +/-5% of full scale over the entire recommended probe-to-surface separation range of 5 mm to 25mm.	Better than +/-5% of full scale over the entire recommended probe-to-surface separation range of 30 mm to 60 mm.
Dimensions	31 mm H x 59 mm W x 173 mm D (1.2” H x 2.3” W x 6.8” D).	31 mm H x 59 mm W x 183 mm D (1.2” H x 2.3” W x  7.2” D).
Weight	200 g (7 oz), with battery	200 g (7 oz), with battery
Power On/Off	A push-button switch
Stability Drift with Time Drift with Temperature	Less than 600 ppm/hour, noncumulative Less than 600 ppm/°C
Operating Time	8 hours with a new battery
Hold	A push-button switch that, when pressed, commands the voltage display to hold the value displayed until the switch is released.
Voltage Display 3 ½ digit liquid crystal display.
Range	0 to +/-1999 V		0 to +/-19.99 kV
Resolution	1 V		10 V
Sampling Rate	2.5 readings per second
Zero Offset	Less than +/-4 counts
Power Requirements	One (1) 9-volt NEDA 1604 battery, IEC 6R61 battery, or equivalent
Ground Receptacle	Snap-on connector
Operating Conditions Temperature Relative Humidity	15°C to 35°C To 85%, noncondensing