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TriOxmatic® 702 IQ
Providing similar performance data as the TriOxmatic® 701, the 702 IQ model is specifically designed for trace level measurements in the ppb range. This sensor is ideally suited for use in ultra-pure water applications; e.g. monitoring of boiler feed water or drinking water purification. The applied digi- tal technology permits integrated storage of calibration values and simple connection to IQ SENSOR NET.
The electrochemical sensors of the TriOxmatic® series
The TriOxmatic® series (ECDO): proved and tested...
ECDO stands for Electrochemical Dissolved Oxygen Sensor. 60 years ago, Clark’s cell was introduced and WTW was among the first manufacturers to advance this principle for water and wastewater applications.
• Well proven technology
• Low investment costs
• Self-diagnosis system SensReg/SensLeck through 3-electrode system
The electrochemical principle
With the electrochemical method the O2 diffuses through the membrane of the TriOxmatic® sensor. The oxygen is transformed in a chemical reaction by using an electrolyte; thereby a current can be measured. The electrical current correlates to the oxygen concentration. For delivering precise results, the sensor will require the following conditions:
• Continuous exchange of electrolytes
• Clean membrane
Patented Technology – 3 electrode system
In contrast to conventional membrane covered oxygen sensors equipped with 2-electrode technology, the TriOxmatic® sensor functions with a potentiostatically driven 3-electrode system. In terms of measuring technology, this means that the measuring system has two silver electrodes and a gold cathode (A). One silver functions as a non-current bearing reference electrode (R). And, the other is the live, counter electrode (G). The reference electrode thus displays significantly improved potential constancy, which in turn leads to considerably improved sensor signal stability and thus higher measuring accuracy.
The 3-electrode technology additionally allows precise monitoring of the electrolyte supply, i.e. the system displays when the electrolyte solution needs to be replaced.
All parts being relevant for the measurement, such as membranes are automatically monitored by the SensReg (used electrolyte)/SensLeck (leakage in the membrane) system. Any occurring incidents will be shown.
Maintenance-free due to special membrane
The membrane or the membrane cap plays a decisive role in all DO measuring techniques. Fouling or mud covering of the membrane or of the cap will affect the measurement reading. Unlike conventional membranes the Teflon membranes used by WTW are highly resistant to fouling. This allows operation without the use of additional cleaning accessories in most cases.
WTW sensors feature extremely low maximum errors of 1% of the measured value (i.e. 0.02 mg/ml at a measured value of 2 mg/ml), regardless of whether measuring in the upper or in the lower range of the instrument.
All WTW ECDOs provide stable and reproducible readings right from the start:
• No break-in
• No long-term drift
• No zero point drift due WTW‘s patented TriOxmatic® principle.
O2 concentration 0 ... 2000 µg/l
0.00 ... 10.00 mg/l
O2 saturation 0...110%
Electrochemical D.O. Sensors TriOxmatic® Series
201 646 TriOxmatic® 702 IQ Digital D.O. sensor for trace level measurements in the ppb range, e.g. ultrapure water/boiler feed water, for use with IQ SENSOR NET.
Supplied with accessory kit (ZBK 25i) comprising: 2 exchange membrane heads (WP 25i/2), 50 ml electrolyte solution (ELY/A), 50 ml cleaning solution (RL-AG/Oxi), 1x cathode cleaner (SF 300), without connection cable (SACIQ order separately)