Light Weight Deflectometer with 1000 test memory

Light Weight Deflectometer with 1000 test memory

loading unit, load plate and settlement meter in carrying case.

Other StandardsASTM E2835-11
Approx. Weight (kg)31
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The light weight deflectometer is used to determine the soil bearing capacity and compaction or consolidation of soils and non-cohesive sub bases, as well as for soil improvement applications. The test method is suited for coarse-grain and mixed-grain soils having maximum grain size of 63mm.

Testing inbuilt soil layers can be carried out very quickly and without requiring a vehicle, which means it is also suitable for sites that are difficult to access. The machine is used in many areas - in road construction, railway engineering and earthworks, for quality protection in canal construction and utility trenches, and in the examination of roadbeds and foundation fillings.

Consisting of:

  • Loading unit with bubble level
  • Load plate with acceleration transducer
  • electronic settlement measuring instrument, in protective case
    • displaying and storing of settlement data, settlement speed and curve
    • (relation s/v) and deformation modulus Evd
    • large colourful graphic display 3,5", lightsensor-controlled backlighting
    • > guarantees optimum readability at all weathers!
    • very comfortable, intuitive menu navigation
    • integrated GPS
    • interface for USB, Bluetooth, thermal printer and PC
    • efficient, fast 32-bit processor
    • internal memory for up to 1000 tests
    • high-performance rechargeable lithium-polymer-battery
    • > guarantees constant readiness for use
  • charger 12V/USB, adapter 230V, USB cable A/A
  • Road construction
  • Testing of pavement bedding
  • Quality assurance in canal and sewer construction
  • Compaction tests in ducts and trenches
  • Backfill of foundations
  • Railway construction


  • large graphic display (62 x 35 mm) comfortable menu navigation
  • acoustic signal when ready to measure Bluetooth interface
  • printer port
  • GPS port
  • internal memory for 500 tests
  • more than 1000 tests with one battery charge
  • 2 year warranty
  • 10 years of spare parts availability guaranteed

Test Procedure


    1. level the test area
    2. lay down the full-size load plate
    3. put loading mechanism onto it
    4. connect it with measuring instrument


    1. switch on, confirm mode 'Measuring'
    2. follow the instructions in the display
    3. perform successively 3 precompacting impacts & 3 measuring impacts
    4. displaying the settlement after each impact


    1. automatic calculation and displaying all measured data and the Evd value
    2. save the measurement, print and transfer it
    3. showing the GPS and curve data after completion of the measurement

Start display

Welcome. The start display shows the charging sta-tus of measuring device + printer and also the GPS +  Bluetooth activity. Warnings will additionally inform you about critical values, so that your testing device is al-ways optimally ready for operation.


After activating the menu item with ENTER you will be guided through the measurement process. 
An acoustic signal indicates the readiness to measure. 
The internal plausibility control avoids measurement errors.
After the third impact, the individual settlement amplitudes, the average settlement Sm, the de-formation speed and the calculated Evd-value will be shown.
You can have a look at the measurement series and its GPS + curve data, print out directly (if unit with printer has been purchased), re-ject or upload for later processing.


Adjust the display and device confi-gurations to your requirements. Re-garding menu navigation just choose one of the various languages and use nationally usual measuring units.

Measured data

Here you can find all stored measu-rements clearly arranged for further processing and documentation

SL416 Specification

Measuring Instrument

Settlement measuring range 0,1 to 2,0 mm ± 0,02 mm
Measuring range Evd < 225 MN/m²
Temperature range 0 to 40 °C
Very robust, splash-water proof, connection cable
with high-quality LEMO connectors
Graphic display 56 x 73 mm
colourful, lightsensor-controlled and illuminated
Fast, efficient 32-bit processor
Bluetooth, USB, thermal printer interface
Dimensions 210 x 100 x 31 mm
Storage capacity, internal - 1000 measurement series
Power supply - high-performance rechargeable lithium-polymer-battery 3,7 V, 6300 mAh
Menu navigation (18 languages available)

Loading Mechanism

Total weight 15,0 kg
Drop weight 10,0 kg
Max. impact force 7,07 kN
Duration of impact 17,0 ± 1,5 ms
Material: zinc coated/hard-crome plated steel
Spring element 17 disk springs

Load plate

Diameter 300 mm, Plate thickness 20,0 mm
Total weight 15,0 kg, Material: zinc coated steel


See SL417, SL418 and SL419 for units with printer and software.