Hydraulic Flow Measurement


Part No. ND2

for slope detection of moving weir flaps

The new electronic NDW 2 inclinometer utilises a modern measurement method based on MEMS technology for gravitational inclination measurement (rotational angle measurement).

  • Ex approval II 2 G Ex ib IIB T4 (optional)
  • Wear-free
  • Corrosion-proof
  • No moving parts
  • Robust design
  • High accuracy
  • Maintenance-free
  • Reliable
  • High operational safety
  • Fully immersible (IP68)
  • Mercury-free


By detecting inclination without the use of shafts it is possible to capture the position of movable weir flaps or other movable and inclinable components such as sluice boards or slide valves without any problems. Overflow volumes or other flow volumes thus can be easily determined by using a Q/h relation or detected angles.
Existing weir flaps can be easily retrofitted by installing the unit on the inclined plane.

NDW 2 combines high accuracy and operational safety with robust design.
The compact unit is free of wear since the measurement principle does not use any movable parts and hence provides reliable measurement results even under flood conditions (IP68).
NDW 2 provides a 4 - 20 mA signal proportional to the angle of inclination (0 - 90° or 0 - 60°) to obtain overflow data.
Following devices such as HydraulicCal-culator Plus, NivuCont Plus, NivuFlow, NivuLog or PCS/SCADA systems use flap-specific data to compute accurate overflow volumes.

Technical Data
Storage temperature

−30 °C to +70 °C



Settling time

1s / 90%

Influence of temperature

< ± 0,5° [ 0 - 60 °C]

Measurement uncertainty

± 0,5°



Power supply

18 to 28 V DC

Power consumption

60 mA at 24 V DC, max. 80 mA

  • 4-20 mA, galvanically isolated
  • load: max. 500 Ohm
Measurement range
  • 0 ... 60° (clockwise)
  • 0 ... 90° (clockwise)
  • Protection class IP 68
  • Material: Stainless steel 1.4571, polyurethane
Connection cable

6-wire shielded single conductor cable, not removable

Cable lengths

10 / 20 / 30 / 50 / 100 m

Operating temperature

−20°C to +60°C

Specifications subject to change.


Data Sheet NDW 2 Inclinometer

Declaration of Conformity NDW2

System Products

Haven't found the appropriate product?

You haven’t found the right product? Then use our application configurator – it will get you to the right product step by step.

Also for your individual measurement spot we support you gladly. Please fill in our questionnaire.

Product Consultation

You want to have best information about our products? Our experts will gladly develop together with you the best system solution for your application.


You have questions about your NIVUS products in use? Our service hotline will readily support you.

We are glad to have you here! For any question regarding water or digitisation we are happy to answer you call or your email message.
Im Täle 2
75031 Eppingen