SS – Suspended Solids Measurement Sensor

DETECTRONIC SS – Suspended Solids Measurement Sensor

The ORAKEL suspended solids measurement sensor has a wide dynamic range that eliminates the need for “zero” and also eliminates the influence of backlight. The suspended solids sensor monitors turbidity and suspended solids from 2 NTU (1mg/l) to 8%* solids for multiple measuring ranges.

The sensor uses lifetime optical technology to provide a stable, reliable, low-maintenance sensor with no moving parts and no consumables. Determines the suspended solids concentration or turbidity in water using a measurement of backscattered light.

Each sensor is equipped with an infrared LED emitter light source and two matching photodiode detectors to make the measurements. It has two detectors placed at different distances from the light source. This allows the sensor to be used in a wide range of suspended solids concentrations.

Detectors are positioned to detect backscattered light (<90° scattered light). The sensor, which measures backscattered light, is used to detect low and high solids concentrations. The ORAKEL controller takes readings at four different light levels. It uses the gradient between readings to produce the sensor output. This means it provides a more accurate measurement of suspended solids and turbidity.

You can contact Aykome Engineering for details.


The sensor is mounted at the end of a pole for immersion in a duct or tank, or in a pipe via a valve that allows retraction and removal of the sensor without shutting down the process.


The sensor is equipped with a cleaning head to keep it clean. This can be used to clean optical windows with a jet of water. The procedure can be programmed to be automated at predefined intervals.


For turbidity measurements or measurements of samples with low solids concentrations, calibration is very easy, requiring only a single calibration sample. This example could be a read from another method or a suitable standard.

The ORAKEL control unit calibrates the sensor, reducing the light output in four steps by taking measurements in each. This process provides an accurate and reliable zero and range without the need to use a “0” NTU/solid sample.

Calibration of the sensor for measurement of samples with high solids concentration uses a multi-point procedure. Up to 5 calibration points can be used to ensure accurate performance over a wide range of sample concentrations.

Suspended Solids Measurement Sensor Application Areas

  • Level and Depth
  • flow
  • heat
  • pH
  • Dissolved Oxygen
  • conductivity
  • biofilm
  • Residual Ozone
  • ORP
  • chlorine
  • blur
  • Suspended Solids
  • Chlorine Dioxide
  • Oil on Water

Suspended Solids Measurement Sensor Technical Specifications

  • Range:
  • Up to 500g/l, 4000 NTU (depending on the optical properties of the sample)
  • Units:
  • Selectable g/l, mg/l, ppm, ppt or % (suspended solids) NTU or FNU (turbidity)
  • Precision:<2% of measured value or 0.01 g/l or 0.8 NTU, whichever is greater
  • Reproducibility: <1% of measured value or 0.001 g/l or 0.8 NTU, whichever is greater
  • Detection limit: 0.001 g/l or 2.4 NTU
  • Resolution: Up to 0.0001g/l or NTU
  • Response Time: T90 ≥ 10 sec (adjustable on average)
  • Drift (electronic): None
  • average: Configurable (10s-10min)
  • Lamp Source: Infrared LED (860nm)
  • Weight: About 1kg (35oz)
  • Process Temperature:0-50°C (32-122°F)
  • Operating pressure: 10 bar (145psi) [maximum]
  • IP rating:IP68
  • Mounting thread (for immersion installation): 1″ BSP
  • Max. power consumption: 70mA at 12 VDC
  • Cable length: 6m (20ft) as standard. (Talk to us if you need a longer length)
  • Wet parts:316 Stainless steel, sapphire
  • Diameter:38mm (1.49 inch)
  • Length:230 mm (9.06 inches)
  • *8% in typical municipal wastewater slurries. This value will vary depending on the optical properties of the sample.