WTW SenTix 22 Plastic PH Electrode with Gel Electrolyte, BNC, 1 m Cable, 103633

The WTW SenTix 22 is a plastic pH electrode with a gel electrolyte. It measures pH values from 0 to 14, has a 1 m fixed cable with a BNC connector and does not have a temperature sensor. For those using a measuring instrument with a BNC input and measuring temperature separately, this electrode offers a basic solution without additional functions.

Design and measurement range

The plastic shaft is 120 mm long and has a diameter of 12 mm. The diaphragm consists of a fibre; a gel serves as the reference electrolyte, and the membrane resistance is less than 1 GΩ. The electrode is approved for use between 0 and 80 °C and is intended for outdoor use. It is supplied with a water-sealing cap fitted.

Without temperature sensor

The shaft, gel and temperature limits are the same as for the SenTix 42. The SenTix 42 also features an NTC sensor and a cable with BNC and banana plugs. If you want the measuring instrument to take the temperature into account automatically, choose the 42. Also available without a temperature sensor are the SenTix 20 with an S7 plug-in head and the SenTix 21-3 with a 3 m cable and a DIN plug.

Day-to-day use

When using the electrode for the first time, remove the storage cap and keep it in a safe place. Any gas bubbles behind the membrane can be removed by shaking the electrode. Between measurements, rinse the electrode with the next solution or with deionised water and gently pat it dry. During breaks and overnight, it should be stored in reference electrolyte (3 mol/l KCl, Ag+-free) or in the cap filled with this solution; never leave it dry and never store it in deionised water. If the cap has dried out, the electrode requires at least 24 hours of conditioning in reference electrolyte. When cleaning, water containing washing-up liquid helps remove grease and oil, whilst a 10 per cent citric acid solution helps remove limescale and hydroxide deposits.

Calibration

Like any pH electrode, the SenTix 22 is calibrated on the measuring instrument. The following applies: briefly rinse the calibration and sample vessels with the solution to be added next, and stir during measurement in a similar manner to calibration. The electrode should be immersed vertically or at a slight angle, only in the region of the shaft. The frequency of recalibration depends on the application.

Typical applications

• Electroplating effluent, industrial effluent and effluent in general
• Aquarium water and swimming pool water
• Groundwater, as well as lake, surface and seawater
• Household cleaning products

The electrode is compatible with WTW buffer solutions (DIN/NIST and technical), reference electrolyte KCl-250 (item no. 109705), the A pHLab/K plastic armature (item no. 903841) and the STH 650 bench stand (item no. 109809).

Technical details

Scope of delivery

• 1 WTW SenTix 22 pH electrode with rinsing cap

Individual requirements and procurement service

For buffer solutions, a separate temperature sensor or replacement electrodes of other designs, the procurement service can advise you at lt-laborhandel.com/service and supply the appropriate accessories.