Oxygen Sensors

What is important for oxygen measurements?

Oxygen measurement today is performed in a very wide range of applications and is one of the most important parameters of process control
technology. Since their introduction in 1995, HAMILTON oxygen sensors have become world leaders because of their signal performance and
low maintenance requirements.

Building on the success of the first OXYFERM sensor, our family of oxygen sensors has been continuously extended and now comprises three
groups. The OXYGOLD sensor with its very low limit of detection has ideal properties for applications in brewing, boiler feed water and for all
applications requiring a low limit of detection. The sterilizable and autoclavable OXYFERM sensors represent a new standard in biotechnology.
In addition to the PG 13.5 versions with their various lengths, they are now also available as 25 mm versions. The OXYSENS sensors have
been developed as 100% maintenance-free, low cost sensors for water management and fish farming.

Measurement principle

The oxygen content in liquids is best measured with cells using Clark's principle. These cells generate an electrical current proportional to the oxygen partial pressure which can be evaluated with a suitable measurement converter. In order to prevent interference effects, the Clark's cell is covered with a gas-permeable membrane. The PTFE membranes typically used, however, are mechanically very fragile, with the result that they must be frequently changed to allow reliable measurement. It is difficult to handle such fragile membranes.

As a solution, HAMILTON developed the OPTIFLOW membrane. This membrane is very mechanically stable and is manufactured as a laminate around a steel mesh. OPTIFLOW membranes are stable under harsh ambient conditions as well as high pressures. This ingenious design allows fast response times to be combined with unusually low flow dependence.

Outstanding performance

Short response times

The outstanding properties of the new membrane material result in fast response times of 30 to 60 seconds.

Low Maintenance and Long Life

Maintenance is rarely necessary due to the improved design of the sensor. The construction of the electrode guarantees excellent stability even after numerous sterilization cycles. The graph illustrates the excellent performance of OXYFERM electrodes even after 100 sterilizations without the need for maintenance.

Low Flow Sensitivity

Many other oxygen sensors show a clear dependence on the flow rate especially with slowly flowing samples. This can lead to excessively low
or erratic readings. As a result of the OXYFERM design, the effect of the flow rate on the reading is negligible.

Short Stabilization Time

The stabilization time is the time between connection of the oxygen sensor to the amplifier and the time when accurate measurements can be expected. This is due to the oxygen, which has diffused inside the sensor and is present around the cathode when no voltage is applied. the OXYSENS stabilization time is typically less than 15 minutes.