Which Reference Electrode Should I Use?

Jun 11, 2025 | Electrochemistry Theory, Technical Articles

Image showing a double junction reference electrode.

It is vital to choose the correct Reference electrode for your application. Having the wrong reference electrode for your test could ruin your results. This article should offer guidance on which reference electrode to use with your application.

The reference electrode is a half cell and the other half of the cell is a sensing electrode such as a pH, Fluoride or REDOX sensor.

Reference electrodes contact the sensor by leaking small amounts of their filling solutions into the sample via a reference junction.

Making sure the filling solution is not going to spoil your test is key. Ensuring the junction suits your application and is not going to get blocked is also important.

EDT directION supply all types of Reference electrodes and their correct storage and filling solutions. We are happy to offer advice to ensure you have the best electrode combination in your sample.

 

 

The chart below should guide you to the correct reference electrode for your application and half cell:

 

Part Number Description Application Use With Junction Filling Solution (Supplied)
E8090 Calomel Single Junction Aqueous Samples. Laboratory Work. Contains Mercury.
Leaches out KCl.		 pH, REDOX, Ca2+ and F- ISE Half Cells. Disbondment Tests. Ceramic 3M KCl
E8095 Ag/AgCl Single Junction Aqueous samples. Laboratory work. Temperatures up to 85
degrees C. Leaches out KCl AgCl.		 pH, REDOX, Half Cells Ceramic Sat KCl w/ AgCl
E8094 Calomel Double Junction ISE work preventing ionic contamination/Interference. Fill solution is changed to suit. Half Cell ISEs Ceramic 0.1M NaNO3
E8195 Ag/AgCl Double Junction ISE work preventing ionic contamination/Interference. Fill solution is changed to suit. Half Cell ISEs Ceramic 0.1M NaNO3
E8197 Solid State KCl No filling or maintenance and continuous monitoring.
Leaches NaCl.		 Half Cell ISEs (Not Na+ or Cl-) Proton Shield None
E8198 Solid State NaCl No filling or maintenance and continuous monitoring.
Leaches KCl.		 Half Cell ISEs (Not K+, NH4+ or Cl- ) Proton Shield None
5094 Flow Plus Awkward or viscous samples. Highly stable and can be deconstructed for cleaning. pH, REDOX and ISE Half Cells Liquid None*
A3135 Gel Filled Ag/AgCl Continuous or process applications. Leaches KCl AgCl. pH, REDOX and Half Cells Teflon None
9999 Cathodic Protection Testing Hull and Metal corrosion. Maintenance free with up to 40 metre cable. 9999ORP Probe/Hull Potential Test Cable Teflon None
E8200 Cathodic Disbondment
Ag/Cl		 Testing efficacy of coating on pipes and metal structures. Cathodic Disbondment Test Rig Ceramic Sat KCl w/ AgCl
E8201 Cathodic Disbondment
Calomel		 Testing efficacy of coating on pipes and metal structures. Cathodic Disbondment Test Rig Ceramic 3M KCl

A downloadable PDF version of this chart is available here:

Reference Electrode Selector

 If you are still unsure on which reference electrode you should be using, you can contact us on: [email protected] .

For more information on reference electrodes please see the articles below on how to store your reference and how to operate them:

 

An image showing a silver-silver chloride reference electrode.

Reference Electrodes: Storage & Filling Solutions

Electrode storage and maintenence is important for many reasons. This article will guide you through which filling and storage solutions are suitable for your reference electrode.

Operating Your Reference Electrode

This article will guide you through operating your reference electrode alongside it’s opposing half cell.