Sensors & Accessories

pH is the single most fundamental measurement in aqueous chemistry — and for good reason. From buffer calibration and drinking water compliance through to bioreactor control and soil analysis, virtually every electrochemical workflow begins here. ELIT combination pH electrodes integrate the pH-sensing glass membrane and Ag/AgCl reference system into a single body, giving you a compact, easy-to-use probe that works with any conventional pH meter or directly with ELIT computer interfaces for fully automated logging. Two models are available: the glass-bodied ELIT P11 (ceramic junction, up to 80 °C) and the epoxy-bodied ELIT P2011 (Teflon junction, up to 60 °C).

Oxidation-reduction potential (ORP) measures a solution's capacity to oxidise or reduce — expressed in millivolts rather than concentration units. A strongly positive reading indicates an oxidising environment (e.g. effectively chlorinated water or well-aerated fermentation); a negative reading indicates reducing conditions (e.g. anaerobic zones or polluted wastewater). Three models are available — ORP-31C (general use), ORP-32C (more demanding applications), and ORP-33C (high precision) — all with platinum sensing elements and Ag/AgCl references for fast, stable mV measurements. Temperature range 0–80 °C, dimensions 12 × 120 mm with 1 m cable and BNC connector.

Dissolved oxygen is one of the most important indicators of aquatic ecosystem health — and a critical control parameter in aquaculture, wastewater treatment, and bioprocess engineering. Low DO signals biological stress in fish ponds, poor treatment efficiency in activated sludge systems, and anaerobic drift in fermenters. ELIT amperometric membrane sensors use an oxygen-permeable membrane and electrochemical cell to give continuous, reliable DO readings in mg/L or % saturation, forming the core of the ELIT 9705b and 9705c Aqualyser systems.

Electrical conductivity measures the total dissolved ion load in a solution — giving a fast, non-specific snapshot of overall water quality or process stream concentration without identifying individual species. It is one of the most cost-effective parameters to monitor routinely, and pairs naturally with ISE measurements: conductivity flags when something has changed, and ISEs tell you what. ELIT conductivity cells are available in three cell constants to cover the full range from ultrapure laboratory water through to concentrated industrial and environmental samples.

Temperature is not simply another parameter — it is a correction factor for every other electrochemical measurement you make. The Nernst equation slope, oxygen solubility, and the conductivity temperature coefficient are all strongly temperature-dependent, so even a 3–5 °C difference between your calibration standards and samples can introduce meaningful error. The ELIT solid-state temperature probe plugs directly into any ELIT computer interface via mini-jack, enabling automatic temperature compensation without any additional software configuration.

Every ISE and pH measurement requires a reference electrode to complete the electrochemical cell — providing the stable, known potential against which your sensing electrode is measured. The choice of reference matters: the wrong filling solution can react with your sample, clog the junction, or introduce contaminating ions that interfere with your analyte. ELIT offers three Ag/AgCl reference electrodes with different outer filling solutions — select the one that suits your sample chemistry, and replace only the reference if it degrades rather than replacing the entire electrode assembly.

The electrode head is the practical hub of every ELIT ISE setup — and an often-overlooked component that makes a real difference to both measurement quality and running costs. Rather than requiring each electrode to carry its own expensive high-impedance cable, the electrode head provides a central mounting assembly with gold-plated, shielded connections that hold the ISE and reference electrode together, route both signals to the analyser, and allow individual elements to be swapped out independently. If your reference fails, replace only the reference; the ISE — usually the higher-value component — stays in service.

Not sure where to start? A complete ELIT ISE system needs just four components: the ion-selective electrode for your target analyte, a reference electrode, an electrode head to mount them together, and a computer interface or ion meter to read the signal. The table below shows a typical single-channel setup with indicative pricing — add a temperature sensor for automatic compensation, or step up to a multi-channel interface if you need to monitor several ions simultaneously.