Product details
Fast-Response Industrial DO Measurement for Process Applications
The InstroDirect IDO-F28i Industrial Fluorescence Dissolved Oxygen Sensor uses fluorescence-quenching optical technology to measure dissolved oxygen concentration in water without a consumable membrane or electrolyte solution. Compared to legacy galvanic and polarographic probes, the optical method delivers longer service intervals, zero oxygen consumption at the sensor face, and no flow-rate dependency — the reading is the same whether mounted in a still tank or a turbulent aeration basin.
The industrial variant trades the compact cap-replacement design of the IDO-F28c for a faster ≤20-second T90 response and lower <0.3 W power draw — purpose-built for fast-cycle process control, aerobic digestion loops, and critical dissolved oxygen measurement in pharmaceutical, brewing, and industrial wastewater applications.
Technical Specifications
| Parameter | Specification |
|---|---|
| Measurement method | Fluorescence quenching (optical) |
| Parameters measured | Dissolved oxygen, temperature |
| DO measurement range | 0–20 mg/L (equivalent to 0–200 % saturation) |
| Temperature range | 0–60 °C |
| Accuracy | ±0.3 mg/L |
| Repeatability | ±0.3 mg/L |
| Resolution | 0.01 mg/L |
| Response time (T90) | ≤20 seconds |
| Drift | ±0.3 mg/L |
| Output signal | RS485 Modbus RTU, up to 115200 bps |
| Power supply | 12 / 24 VDC |
| Power consumption | <0.3 W |
| Housing material | Titanium alloy & 316 stainless steel |
| Ingress protection | IP68 |
| Dimensions | 144 mm × Ø28 mm |
Typical Australian Applications
- Municipal wastewater aeration basin DO monitoring and blower control
- Fish farm and prawn farm raceway DO
- Brewery / fermentation broth DO
- Pharmaceutical process DO
- Reservoir, river, and surface water oxygen profiling
Why Integrators Choose the IDO-F28i
Open RS485 Modbus RTU — no proprietary transmitter required. Integrates directly with Allen-Bradley ControlLogix / CompactLogix, Siemens S7, Schneider Modicon, Beckhoff, and any Modbus-capable SCADA. Stock held in Australia. Technical support from field engineers with 20+ years automation experience.
Why InstroDirect vs Endress+Hauser or HACH in Australia
| Factor | InstroDirect | Endress+Hauser / HACH |
|---|---|---|
| Digital protocol | Open RS485 Modbus RTU — integrates with Allen-Bradley, Siemens, Schneider, Beckhoff, or any SCADA | Proprietary (E+H Memosens / HACH SC digital) — locked to the vendor’s transmitter |
| Technical support | Australian field engineers with 20+ years automation experience | Remote support via offshore ticket queues |
| On-site calibration | InstroDirect technicians available across QLD, NSW, VIC with formal calibration certificate | Third-party authorised service network, longer turnaround |
| Price | Parallel-import model — no distributor margin stack, typically 30–50% below equivalent brand pricing | Premium brand pricing with tiered distributor markup |
| Replacement parts | Standard consumables ordered on demand from InstroDirect | Proprietary cartridges and cells, tied to the brand |
Australian Technical Support, Calibration & Consumables
12-month Australian-backed warranty. On-site calibration service available across QLD, NSW, and VIC. Configurable Modbus slave ID (default 0x01). Register map supplied with every order.
Frequently Asked Questions
Does this sensor need a membrane replaced regularly?
No. The optical fluorescence method has no membrane and no electrolyte. The fluorescent cap itself has a long service life and is replaceable at scheduled maintenance, not as a wear part.
What is the difference between mg/L and % saturation?
mg/L is the absolute mass of dissolved oxygen per litre of water. % saturation is the ratio of measured DO to the theoretical maximum DO at the current temperature and barometric pressure. The sensor outputs both — pick the one your process setpoints use.
Can I use this with Allen-Bradley PLCs?
Yes. RS485 Modbus RTU is supported natively by any 1734-485 Point I/O module, 1756 EWEB gateway, or a standard Prosoft MVI56 gateway. InstroDirect can supply a sample AOI on request.
What consumables will I need?
None under normal operation. Optional replacement fluorescent cap is available as a long-interval service item.
Request a Trade Quote
Bulk or trade pricing available for panel builders, integrators, and OEMs. Contact InstroDirect Australia for volume pricing.
