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Dissolved Oxygen

As the impact of effluent on the ecosystem becomes apparent, many companies increase their commitment to better wastewater management. One of the most important indicators for condition of the natural waters is the level of dissolved oxygen.

Our D.O. sensors include:

Luminescent Dissolved Oxygen sensorwith direct 4-20mA output

The new optical dissolved oxygen sensor that outputs directly a 4-20mA or Modbus signal. Optical DO sensors offer advantages over electrochemical DO sensors in that they are inherently self-referencing, require no warm-up period, do not require flow and are less affected by fouling.

Maintenance is trivial. The sensor cap lasts for an industry leading 3 years or longer and is inexpensive to replace.
The body is corrosion resistant and designed to stand up to the harsh environment of wastewater.
No sensor on the market packs as much into one small package. Plug into your PLC, remote controller or computer and you’re ready to measure.

Technical Data
Measuring Range: 4ppb (0.5% air sat.) to 24 ppm (300%)
Accuracy at 25°C : 1± 0.05%-vol; 21± 0.2%; 50 ± 0.5%
Detection limit: 0.1 % - vol
90% Response Time: Drift at Room Temp.: <0.2%-vol oxygen per week at 30°C
Power input: 7-30VDC. (0.6W)
Analog Output: 4-20mA scalable. Temperature compensated
Polarization voltage: 5-10 min for self heating
Transmission Rate: 4800 to 115,000 bd
Cross sensitivity: None (inc. CO2, H2S, SO2)
Wetted Materials: 316SS, EPDM, silicone
Operation Temperature: -10 to 60°C
Pressure Range: -1 to 12 bar / 174 psi
Wetted materials: CPVC
Not resistant to: Chlorine, Chloroform, Toluene, Acetone
Digital Output: Modbus RTU over RS485
Enclosure type: IP65
Connector: VP 8.0 Variopin connector with PG 13.5
Mounting: PG 13.5-thread, IP68

• Wastewater treatment
• Sewage
• Boilers
• Fish farms
• Aquaculture

Model 91 Dissolved Oxygen Probe

The sensor consist of a probe to which is fitted a cartridge that contains a precisely stretched permeable membrane, electrodes and electrolyte (SH 91D). The inexpensive cartridge will provide continuous service for 6 to 12 months and is the easily replaced in minutes. The cartridge is supplied hermetically sealed for longer shelf life.

  • Supports up to a 4 meter (12-foot) boom
  • Replaceable sensor
  • Ball float minimizes membrane fouling
  • Optional Accessories
  • D.O. Tank Submersion Mounting Hardware
  • D.O. Floatation Mounting Hardware
  • D.O. Flow Thru Mounting Hardware