NBM-520 Broadband Field Meter

Compact Hand Held Device for Measuring Electric and Magnetic Fields.

NBM-520 is part of the NBM-500 instrument family. It gives extremely accurate results for electromagnetic field strength measurements. The NBM-520, like its bigger counterpart NBM-550, handles applications from a few Hertz through to long wave and up to high frequency microwave radiation using a selection of interchangeable probes for electric and magnetic fields.
The field strengths are captured with flat frequency response probes or weighted probes that have shaped time domain characteristics, allowing the measurement values to be assessed against an environmental or occupational safety standard. The calibration factors for each probe are stored in the probe itself and are read out and taken into account automatically by the measuring set.

For more information on the NBM-520 Broadband Field Meter, contact your local Air-Met office. 
  • Non-directional measurement using
  • isotropic probes for applications in the
  • frequency range 100 kHz to 60 GHz
  • Intelligent probe interface with automatic
  • detection of probe parameters
  • for simple operation
  • Extra small and lightweight
  • Unbeatably easy 4-button operation
  • Auto zero ensures precision measurements
Display Type Transflective LCD, monochrome
Display Size 4 cm (1.5”), 128 x 64 dots
Backlight LEDs, selectable illumination time (OFF, 5s, 10s, 30s, 60s, PERMANENT)
Refresh Rate 400 ms
Result Units mW/cm2, W/m2, V/m, A/m (for flat probes)
% (for shaped probes)
Display Range
0.01 to 9999 V/m
0.0001 to 265.3 A/m
0.0001 to 9999 W/m2
0.0001 to 9999 mW/cm2
0.0001 to 9999 %
Result Types (isotropic, RSS) Actual (ACT), Maximum (MAX), Average (AVG), Spatial Averaging (SPATIAL)
Averaging Time 4 s to 30 min (2 s steps), selectable by PC software
Spatial Averaging discrete or continuously, selectable by PC software
Alarm function 2 kHz audible signal (4 Hz repetition), threshold adjustable by PC software
Optical Interface Serial, full duplex, 115200 baud, no parity, 1 start and 1 stop bit
Probe Interface Plug-and-play auto detection, compatible with all NBM series probes

Integration time for measuring input approx. 270 ms
Measurement sampling rate 5 Hz (5/ 50/ 60 Hz for remote operation)
Recommended Calibration Interval 24 months (basic unit only, probes are specified separately)
Battery NiMH rechargeable batteries, 2 x AA size (Mignon), 2500 mAh, included
Operation Time Approx. 22 hours (backlight off)
Approx. 16 hours (permanent backlight)
Charging Time 2 hours
Battery Level Display 100%, 80%, 60%, 40%, 20%, 10%, low level (< 5%)
Temperature Range Operating: -10 °C to +50 °C
Non-operating: (transport) -30 °C to +70°C
Humidity 5 to 95%, non condensing
≤29 g/m³ absolute humidity (IEC 60721-3-2 class 7K2)
Size (h x w x d) 38 x 52 x 195 mm (without probe)
Weight 300 g (without probe)
Accessories (included) Hard case, power supply, rechargeable batteries, shoulder strap, NBM-TS software, operating manual, certificate of calibration
Country of Origin Germany

  • Measuring field strengths to comply with general safety regulations
  • Establishing safe zones
  • Measuring field strengths in the industrial environment, such as plastics welding equipment, RF heating, tempering, and drying equipment
  • Measuring and monitoring field strengths around broadcasting and radar equipment
  • Measuring field strengths of cell phone transmitters and satellite communications systems to demonstrate