Light Weight Deflectometer with 500 test memory and Printer

Light Weight Deflectometer with 500 test memory and Printer

loading unit, load plate, settlement meter and printer  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 meter with display of date and time in carrying case
    • intuitive menu navigation, languages selectable
    • graphic display
    • displaying and storing of settlement data, settlement speed and curve (relation s/v) and deformation modulus Evd
    • storage capability for up to 500 tests
    • interface for USB, Bluetooth, thermal printer and PC
    • compatible with external GPS-receiver (optional
    • very robust and splashproof
  • Thermal Printer
    • small, quick, with light resistant thermal paper for immediate documentation
    • long mobile usability, due to integrated 1,8 AhNiMH power pack
    • incl. charger for vehicle (12V/24V),
    • connecting cable to the electronic settlement measuring instrument,
    • 5 thermal paper rolls
  • 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
SL412 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 38 x 68 mm
Bluetooth, USB, thermal printer interface
Dimensions 211 x 100 x 26 mm
Storage capacity, internal - 500 measurement series
Power supply - 4 x R6 Batteries
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 SL413, SL414 and SL415 for units with printer and software.


ClickClick to view a PDF file of the User Guide

A user guide is available to download from the Impact web site