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ZORN ZFG 3000 | Lightweight Deflectometer

The mechanical components of the ZFG 3000 GPS Lightweight Deflectometer are surface-treated for the load-bearing capacity testing of compacted soils in harsh construction site conditions. For these components we provide compact measuring electronics in a robust case with internal data memory for more than 10,000 measurements, SD card slot and a powerful rechargeable battery for long battery life. A thermal printer and an integrated GPS receiver are also included. You can display the position of the measurement point in the UTM (Universal Transverse Mercator) format or in the traditional Gauss-Krueger co-ordinate system. And if it is dusty, close the cover on the case and operate the device conveniently from the exterior.

Your advantages at a glance

  • Surface-treated mechanical components for testing in construction site conditions
  • Unique, ergonomic triangular catch handle. The triangular design offers improved ease of use of the falling weight and prevents rolling during transport. The handle is manufactured from a single piece without any welded joints prone to fracture. We offer a life-long guarantee for this feature!
  • Loading plate as standard with intelligent adapter spigot to changeover the ZFG to the dynamic CBR (California Bearing Ratio) test
  • Integrated calibration reminder and unique self-test for checking the function of the device
  • As standard, powerful GPS receiver with co-ordinate depiction in the UTM format and! Gauss-Krueger
  • Backlit graphic display with curve display
  • Integrated quality thermal printer for print-outs directly on the construction site
  • First Falling Weight Deflectometer with SD memory card
  • Internal memory for approx. 10,000 measurements, at the same time the data measured are saved automatically on the SD card
  • Entry of additional information about the test via text entry on the device
  • Preloading impacts can be switched off if required
  • Audible signal to confirm valid measurement impacts
  • Integrated plausibility check

Made in Germany – all ZFG devices are manufactured entirely by the highly qualified employees in our ISO-certified production facility in Stendal (Germany). We procure components and accessories from first-class suppliers, predominantly in Germany.

A solid

Basic features

  • Deformation measuring device incl. SD card slot, printer and GPS
  • Loading plate with acceleration sensor and adapter spigot (surface-treated)
  • 10 kg loading device (Evd 15–70 MN/m²)
  • Calibration record
  • Approved calibration certificate
  • Detailed operating instructions


The measurement results from your ZFG 3000 GPS can be analysed directly on the construction site or on your PC in the office.

After the completion of each measurement, the result including all measurement curves can be read on the large, backlit display. The data are automatically saved in the internal memory and! on the SD card inserted.

You can print out the results on-site using the integrated thermal printer. The print-outs contain the dynamic deformation modulus Evd, the individual deformations and average values, the ratio of deformation to deformation speed (s/v), as well as the GPS position and the text entry for the location of the measurement.

With the aid of the SD card it is possible to transfer up to 10,000 measurements safely to a PC and the ZORN FG software. The software makes it possible to depict the individual measurement records with all the detailed information, comprehensive reports as well as the evaluation in a static display. Interfaces to different map providers such as Google Maps make it possible to depict the related measurement points on the map or satellite image. The co-ordinates can be depicted in UTM format or the Gauss-Krueger system.

The documentation of your test is therefore reliable and at the same time very easy.


  • Three loading plate deformations with deformation curves and the average value
  • Three deformation speeds with average value
  • The s/v value as an indicator for the compactability of the soil tested
  • The deformation modulus Evd as a measure of the quality of the compaction and for the assessment of the load-bearing capacity


You obtain the result in only 2 minutes.

The operation of the Lightweight Deflectometer ZFG is convenient and easy because, during its design and development, attention was paid to ensuring incorrect measurements are automatically excluded by an internal plausibility check. In this way it is ensured that a layperson can operate the Lightweight Deflectometer correctly after brief instruction and can undertake precise measurements on soil compaction.

The procedure for the measuring process demonstrates the easy, quick implementation of the measurement that can be printed out immediately on the construction site using the integrated mini-printer and saved on the SD card for subsequent print-outs on a PC.

Advantages in a glance

  • Testing in narrow locations (e.g. pipe trenches, bridge underpasses, etc.)
  • No loading vehicle necessary
  • Very short test duration of two minutes
  • Easy handling and evaluation