Details

Hanna Instruments offers a wide variety of pH electrodes that are designed for many different applications. The type of glass used for sensing pH, bulb shape, body material, type of junction, type of reference and electrolyte used are just some of the design considerations.

The FC2143 uses high temperature (HT) glass, spherical bulb, titanium body, and cloth junction with gel electrolyte.

General Purpose Glass Formulation

The measurement of pH at very high temperatures is detrimental to the sensitive glass bulb and will shorten the life of it. A pH electrode with general purpose (GP) glass will have a resistance of 100 megaohms at 25^°C while the resistance of LT glass is around 50 megaohms at 25^°C. As the temperature of the glass decreases in the sample, the resistance of the LT glass will approach that of GP glass. If using GP glass, the resistance would increase above the optimum range, resulting in increased impedance and ultimately affecting the measurement. The FC2143 is suitable to use with samples that measure from 0 to 80 °C.

Flat Tip Bulb

The recessed flat tip bulb of the FC2143 is easy to clean and prevents solids in solutions from collecting on the sensor. Other tip shapes include conic for penetration and spheric for aqueous measurements.

Titanium Body

A pH measurement is a very sensitive voltage measurement that is susceptible to interference from electrical noise and humidity.  To overcome these issues a titanium body serves as a matching pin. A matching pin is a differential measurement technique used to eliminate electrical noise in the measurement system. The titanium body, being made of metal, is virtually unbreakable and  offers additional protection from accidental breakage.

Cloth Junction

Every pH electrode has a junction. They can be made from a variety of material including ceramic, PTFE, and a fiber wick. The fiber wick is also known as a cloth junction and is often used on electrodes with gelled electrolytes. The advantage of the cloth junction is that it can be extracted from the probe exposing a fresh surface. This is very important since one of the major contributors to unstable measurements is a clogged junction. This is likely to occur when measuring the pH of mash that has a high solids content. Having the ability to pull out a small portion (⅛”) of the junction will clear any clogging resulting in an increased life of the pH electrode.

DIN Connector

The FC2143 uses a quick connect DIN connector. This type of connector is proprietary to the meter they are to be used with. The FC2143 is the replacement electrode for the HI99151. Other type of connectors include BNC, screw type, T-type, and 3.5mm.