WTW SenTix 21-3 Plastic PH Electrode with Gel Electrolyte, 3 m Cable, 103632
€209.00
% Manufacturer's RRP: €232.00 9% below manufacturer's RRP
- 3 m fixed cable with waterproof DIN plug (coaxial plug to DIN 19262)
- Plastic shaft 120 x 12 mm with gel electrolyte and fibre diaphragm
- Measuring range 0 to 14 pH, temperature range 0 to 80 °C
- Membrane resistance less than 1 GΩ
- Without temperature sensor
- For waste water, aquarium and swimming pool water, groundwater and surface water
Product information "WTW SenTix 21-3 Plastic PH Electrode with Gel Electrolyte, 3 m Cable, 103632"
The WTW SenTix 21-3 has a 3-metre fixed cable with a waterproof DIN plug. The rest is identical to a standard gel electrode with a plastic shaft.
Fixed cable instead of a plug-in head
Unlike the SenTix 20 with its S7 plug-in head, the cable on the SenTix 21-3 is permanently attached to the measuring chain. It terminates in a waterproof DIN plug, a coaxial plug in accordance with DIN 19262. There is no need to order a separate connection cable; the electrode is ready for connection once the protective cap has been removed and it has been plugged into the measuring instrument.
Plastic shaft with gel electrolyte
The shaft is made of PPE/PS and measures 120 mm in length with a diameter of 12 mm. The membrane is cylindrical, the diaphragm is made of fibre, and the reference system is a gel. The pH measurement range is 0 to 14; the permissible temperature range is 0 to 80 °C; the membrane resistance is less than 1 GΩ.
Measuring temperature separately
A temperature sensor is not fitted. Measuring instruments with automatic temperature compensation require a second sensor for this purpose, or the temperature must be entered manually. If you wish to transmit both pH and temperature via a single cable, choose the SenTix 41-3 with an integrated NTC sensor, also supplied with a 3 m cable.
Handling and storage
Gas bubbles behind the membrane must be removed by shaking the unit before taking a measurement. Between measurements, the measuring chain should be placed in reference electrolyte (3 mol/l KCl, Ag+-free), and left overnight in the irrigation cap filled with this solution. Electrodes stored in a dry state or in deionised water may suffer permanent damage. Proteins, fats, oils, strong acids and alkalis, hydrofluoric acid and organic solvents shorten the service life. For fats and oils, rinsing with water containing washing-up liquid helps; limescale deposits can be removed with a 10 per cent citric acid solution.
Typical applications
- Electroplating effluent, industrial effluent and effluent in general
- Aquarium water and swimming pool water
- Groundwater, lake water, surface water and seawater
- Household cleaning products
Technical details
| Type | Plastic pH electrode with gel electrolyte |
| Sensor shape | Cylinder |
| Shaft material | Plastic (PPE/PS) |
| Shaft length / Shaft diameter | 120 mm / 12 mm |
| Diaphragm | Fibre |
| Reference system | Gel |
| pH measurement range | 0 to 14 pH |
| Temperature range | 0 to 80 °C |
| Membrane resistance | < 1 GΩ |
| Temperature sensor | None |
| Connection | 3 m fixed cable with waterproof DIN plug (coaxial plug to DIN 19262) |
| Standards | EU Declaration of Conformity (RoHS Directive 2011/65/EU), WEEE marking |
Scope of delivery
- 1 WTW SenTix 21-3 pH measuring chain with irrigation cap and fixed 3 m cable
Individual requirements and procurement service
For the KCl-250 reference electrolyte (order no. 109705) for storage, buffer solutions for calibration, the A pHLab/K plastic armature, or a SenTix with a different cable length and plug, our procurement service is at your disposal. A brief enquiry specifying the measuring instrument is sufficient; we will then determine the appropriate version.