Fluorescence-quenching measurement with no oxygen consumption and no sample-flow requirement
Optical online analyzer · PFDO-500
Aquaculture Fluorescence Dissolved Oxygen Analyzer
The smallest documented sensor in the series—25 × 127 mm and 0.3 kg—configured for aquaculture and low-pressure continuous monitoring.
0–20 mg/L≤0.1 MPaØ25 × 127 mm
Model-specific values checked against the supplied sheet
Pressure, construction, dimensions and weight are not copied between the four PFDO models. Final mounting, cable, seawater material, cleaning and control interfaces are controlled by the project confirmation.
01
Measurement principle and product highlights
Oxygen-sensitive film with integrated NTC temperature compensation
No membrane or electrolyte replacement stated in the supplied specification
Air automatic calibration and sample calibration
Three 4–20 mA outputs, three configurable relays and Modbus RS485
Reverse-polarity protection for sensor power and RS485 A/B wiring
Time display, data storage, historical-data review and optional wireless transmission
02
Verified technical specifications
Confirm freshwater or seawater, normal and peak DO, temperature, pressure, immersion depth, mounting, cable length, fouling risk, power supply and required 4–20 mA / relay / Modbus signals before quotation.
- Dissolved oxygen range
- 0–20 mg/L
- Saturation range
- 0–200%
- Temperature range
- 0–45°C
- DO accuracy
- ±3% of reading or ±0.3 mg/L, whichever is greater
- Temperature accuracy
- ±0.5°C
- Repeatability
- ±0.3 mg/L
- Resolution
- 0.01 mg/L
- Pressure rating
- ≤0.1 MPa
- Calibration
- Automatic air calibration; sample calibration
- Sensor construction
- SUS316L
- Power supply
- 85–500 VAC; 9–36 VDC
- Analog output
- 3 × 4–20 mA
- Relays
- 3 configurable relays
- Digital communication
- Modbus RS485
- Storage temperature
- -15–60°C
- Operating temperature
- 0–45°C, non-freezing
- Sensor dimensions
- Ø25 × 127 mm
- Transmitter dimensions
- 145 × 125 × 162 mm
- Sensor weight
- 0.3 kg
- Transmitter weight
- 1.35 kg
- Sensor protection
- IP68 / NEMA6P
- Transmitter protection
- IP66 / NEMA4X
- Cable
- 10 m standard; extendable to 100 m
03
Recommended process fit
Aquaculture ponds
Continuous oxygen checks for ponds and culture tanks.
Recirculating aquaculture
Use DO trends to support aeration and recirculation operation.
Freshwater treatment
Compact low-pressure monitoring in treatment and reuse systems.
Field monitoring
Integrate continuous DO into compact project cabinets and telemetry.
04
Items to confirm
All four models share the documented core measurement range, but sensor size, weight, pressure rating and construction options differ. Select using the real operating conditions.
- 01Freshwater, seawater, wastewater or aquaculture water
- 02Normal and peak DO, temperature and pressure
- 03Immersion depth, mounting, maintenance access and fouling risk
- 04Cable, power, 4–20 mA, relays and Modbus RS485
05
Project documents available on request
After receiving the operating conditions, we prepare the current configured datasheet, installation confirmation and project quotation. Images provide consistent public presentation; verified specifications remain the technical source.
Get a quote- Configured model datasheet→
- Mounting and immersion confirmation→
- Cable and I/O schedule→
- Project quotation→
06
Compare other PFDO models
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Compact Fluorescence Dissolved Oxygen Analyzer
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Model confirmation
Do all four models use the same range?+
The supplied sheets state 0–20 mg/L or 0–200% saturation and 0.01 mg/L resolution for all four. The key differences are pressure, dimensions, weight and construction.
What is the documented difference between PFDO-700 and PFDO-800?+
Both are full-size ≤0.3 MPa configurations. The supplied sensor lengths are 252.3 mm and 251.5 mm respectively. Final project accessories and mounting still require confirmation.
Which configuration is documented for seawater?+
The PFDO-700 and PFDO-800 sheets explicitly list a titanium-alloy seawater body. Seawater construction must be confirmed in the quotation and order configuration.
Contact FUNEL
Tell us what you need to measure.
We will respond with a recommended configuration, supporting documentation and quotation.