WTW SenTix 61 glass pH electrode, refillable, DIN connector, 103640

Precision thanks to liquid electrolyte

The WTW SenTix ® 61 is a high-quality standard pH electrode with a glass shaft, designed for demanding measurement tasks in the laboratory. Unlike gel-filled electrodes, this model utilises a liquid reference electrolyte (3 mol/l KCl, free from silver ions). This ensures a faster electrolyte flow and more stable potential formation, particularly with difficult samples. As the electrolyte is refillable, the user benefits from a significantly longer service life for the electrode compared with maintenance-free models.

High-quality platinum diaphragm

The built-in platinum wire diaphragm ensures a reliable connection between the sample and the reference system. It is characterised by a constant flow rate and is less prone to blockages than conventional ceramic diaphragms. The robust glass shaft is highly chemically resistant, easy to clean and ideally suited for use across a wide temperature range from 0 to 100 °C.

Compatibility and connection

The SenTix ® 61 (variant 103640) is fitted with a permanently attached 1-metre cable and a waterproof DIN plug. This connection standard ensures reliable signal transmission and is perfectly compatible with numerous WTW pH metres (e.g. the inoLab ® series) as well as other measuring instruments with a DIN socket. Please note that this model does not have an integrated temperature sensor; temperature measurement must be carried out separately if required.

Technical details

• pH measurement range: 0 – 14
• Temperature range: 0 – 100 °C
• Reference electrolyte: KCl 3 mol/l (liquid, refillable)
• Diaphragm: platinum
• Shaft material: Glass
• Shaft length / diameter: 120 mm / 12 mm
• Temperature sensor: No (NTC not integrated)
• Connection: DIN plug (waterproof)
• Cable length: 1 m (fixed)
• Diaphragm shape: Cylinder
• Diaphragm resistance (at 25°C): < 600 MOhm

Contents of delivery

• WTW SenTix ® 61 pH electrode
• Fixed cable (1 m) with DIN plug
• Operating instructions

Note: An initial supply of electrolyte is included; refill bottles must be ordered separately.

Customised requirements & procurement service

Do you need the correct electrolyte solution (KCl 3 mol/l), storage solution or a model with an integrated temperature sensor (e.g. SenTix 81)? We can advise you on optimal electrode maintenance. Please contact our procurement service for accessories and spare parts.