Product Description
The right probe is what turns a good meter into accurate results, and matching electrodes keep calibrations and readings consistent. OHAUS Starter Series electrodes cover pH, reference, ORP, conductivity, dissolved oxygen and temperature measurement for Starter and Aquasearcher bench and portable meters.
This listing is for OHAUS item number 30378544: Starter Optical Dissolved Oxygen Sensor STDO21, 1 m Cable, for ST400D Portable Meters. Models are available with plastic, glass or metal shafts, standard and IP67 waterproof versions, and cable lengths from 1 m to 5 m. Specialty designs include micro pH electrodes for small vessels, a pure-water pH electrode, a flat surface electrode, low-range conductivity cells with a flow chamber and optical DO sensors. Check the compatible meter list for each model, and replace electrodes as they age to maintain response and calibration slope. LIGHT LABS supplies the OHAUS line with knowledgeable support from our Englewood, Colorado team.
Key Features
- Complete Range – pH, ORP, reference, conductivity, DO and temperature probes
- Meter Matched – designed for Starter and Aquasearcher meters
- Shaft Options – durable plastic or chemically resistant glass bodies
- Specialty Designs – micro, surface, pure-water and flow chamber versions
- IP67 Options – waterproof probes with 3 m cables for field meters
Specifications
| Item Number | 30378544 |
| Brand | OHAUS |
| Description | Starter Optical Dissolved Oxygen Sensor STDO21, 1 m Cable, for ST400D Portable Meters |
| Electrode Type | DO |
| Measurement Range | 0.00 – 20.0 mg/L(ppm) |
| Cable | 1 m |
| Shaft Material | Plastic |
| Dimensions | 4.9 in x 0.63 in (125 mm x 16 mm) (LxØ) |
| Applicable Meters | ST400D |
| Measurement Range DO | 0 % – 20 ppm |
| Net Weight | 3.7 oz (105 g) |
| Temperature Range | 0 °C – 60 °C |
| Temperature Sensor | No |
| Working Environment | 50°F – 104°F, 85%RH, non-condensing (10°C – 40°C, 85% RH, non-condensing) |
Related Models
- 83033972 – Starter Conductivity Electrode STCON3, 2 µS/cm-200 mS/cm, Plastic Shaft, 1.1 m Cable
- 30468962 – Starter Conductivity Electrode STCON3 IP67, Waterproof, 3 m Cable, for ST400M Meters
- 30080693 – Starter Conductivity Electrode STCON7, for Aquasearcher AB33EC Bench Meters
- 30681235 – Starter Conductivity Electrode STCON8 with Flow Chamber, 0.055-300 µS/cm, Glass Shaft
- 30681116 – Starter Conductivity Electrode STCON5, 50-2,000 µS/cm, Glass Shaft, 1 m Cable
- 30681117 – Starter Conductivity Electrode STCON8, 0.055-300 µS/cm, Glass Shaft, 1 m Cable
- 30031639 – Starter Dissolved Oxygen Electrode STDO11, 0-200%, for ST300D Portable Meters
- 30378545 – Starter Optical Dissolved Oxygen Sensor STDO21, 5 m Cable, for ST400D Portable Meters
- 30038555 – Starter ORP Electrode STORP1, -1,000 to 1,000 mV, Plastic Shaft, 1.1 m Cable
- 30038553 – Starter ORP Electrode STORP2, -1,000 to 1,000 mV, Glass Shaft, 1.1 m Cable
- 83033966 – Starter pH Electrode ST210, 0-14 pH, Plastic Shaft, 1.1 m Cable
- 83033968 – Starter pH Electrode ST230, 0-14 pH, Glass Shaft, 0-100 °C, 1.1 m Cable
- 30240974 – Starter pH Electrode ST270, 0-14 pH, Glass Shaft, 0-100 °C, 1 m Cable
- 30393265 – Starter pH Electrode ST272, 2-12 pH, Plastic Shaft, 160 mm Length, 1 m Cable
Applications
- Replacement probes for bench meters
- Field pH and conductivity testing
- Pure water conductivity
- Small-volume pH measurement
- Dissolved oxygen monitoring
