Dissolved Oxygen Probes STDO11 (0 – 200%)

Dissolved Oxygen Probes

Basic Principle of Dissolved Oxygen (DO) Probes

There are three types of commonly used oxygen sensors: polarographic, galvanic and optical (luminescence) sensors. STDO11 is a galvanic DO probe and the simplest among the three probes. It produces its own electric current. The cathode is silver and the anode is zinc. Oxygen passes through the membrane and is reduced at the cathode to increase the electrical signal (current) read by the electrode. As oxygen increases, the signal increases. Galvanic sensors are active at all times and will degrade in storage as well as during use. They do not need to polarize (warm up) before calibration or measurement while polarographic electrodes take 15 minutes to several hours to warm up.

Care and Maintenance

Carefully remove the protective bottle from the tip of the electrode by unscrewing the lid and removing the bottle. Remove the shorting plug from the connector and store in a safe place. Be careful because the protective bottle lid is tightly fit on the electrode. STDO11 should be stored in a moist environment to keep the membrane from drying out, but do not store directly in water.

Calibration and Measurement

DO probes should be calibrated before being placed in the sample. Before calibrating a probe, do not forget to remove water droplets from the membrane by gently shaking the sensor.