WTW SenTix HW-T 900 digital IDS pH electrode (1.5 m fixed cable), 103753

The WTW SenTix® HW-T 900 is the digital reference electrode for problematic samples in laboratory analysis. Equipped with intelligent IDS technology, this sensor features an adjustable ground joint diaphragm. This design solves one of the most common problems in pH measurement: clogged diaphragms in protein-rich, suspended or low-ion media. Simply lifting the movable ground sleeve increases the electrolyte flow, which facilitates contact with the sample even in difficult matrices (e.g. emulsions, cosmetics or boiler feedwater) and flushes out contaminants.

Signal quality and QSC intelligence

Unlike analogue electrodes, the SenTix® HW-T 900 converts the sensitive measurement signal directly into digital data within the sensor head. This data is transmitted via the permanently integrated 1.5-metre cable to the IDS meter (e.g. MultiLine® or inoLab®). Thanks to the QSC (Quality Sensor Control) function, the electrode stores its calibration history and serial number internally. In day-to-day laboratory work, this means you can use the electrode on different instruments without having to recalibrate it each time: the calibration data ‘travel’ with the sensor.

Design and maintenance

At 165 mm, the glass shaft is slightly longer than that of standard electrodes, which makes it easier to use in taller vessels. A liquid electrolyte (KCl 3 mol/l) serves as the reference system and can be topped up via the side opening. This significantly extends the electrode’s service life compared with gel systems, as the electrolyte supply is not ‘exhausted’ but is replenished. An integrated 30 kOhm NTC sensor simultaneously provides the exact sample temperature for automatic compensation.

Technical details

• pH measurement range: 0.000 … 14.000
• Permissible temperature range: 0 … 60 °C
• Accuracy (pH): ± 0.004
• Diaphragm: Adjustable annular gap (ground joint)
• Membrane glass resistance: < 600 MOhm
• Shaft material: Glass
• Shaft length: 165 mm
• Shaft diameter: 12 mm
• Electrolyte: Liquid, KCl 3 mol/l (refillable, silver-ion-free)
• Temperature sensor: Integrated (NTC 30 kOhm)
• Connection: 1.5 m fixed cable with waterproof digital connector (IDS)
• Signal type: Digital (IDS)

Scope of delivery

• SenTix® HW-T 900 electrode (incl. 1.5 m fixed cable)
• Operating instructions

Individual requirements and procurement service

Do you actually need this electrode in the plug-in head version (“-P”) for use with wireless modules? Or are you looking for the analogue version (SenTix HW) for older pH meters with a DIN/BNC input? We can source any WTW special-purpose electrode and the appropriate cleaning solutions (e.g. pepsin/HCl) for you.