Reference Electrodes: Filling & Storage Solutions
It is important to know which Filling & Storage Solutions should be used with your Reference Electrodes. Choosing the correct solutions can prolong the life of your electrode and improve it’s performance.
Some Reference Electrodes have an internal filling solution as well as a storage solution. The solution used to fill the electrode is not always the same as the solution in which the electrode should be stored.
EDT directION provide a full range of Storage Solutions & Filling Solutions. These are either provided with the electrode or can be purchased separately.
The guide below should help you select the correct solutions for your Reference Electrode.
Part Number |
Description |
Filling Solution (Supplied) |
Storage Solution |
| E8090 | Calomel Single Junction | 3M KCl | 3M KCl |
| E8095 | Ag/AgCl Single Junction | Sat KCl w/ AgCl | 3M KCl w/ Ag/AgCl |
| E8094 | Calomel Double Junction | Inner: 3M KCl | Outer: 0.1M NaNO3 | 1M NaNO3 * |
| E8195 | Ag/AgCl Double Junction | Inner: 3M KCl/Sat AgCl | Outer: 0.1M NaNO3 | 1M NaNO3 * |
| E8197 | Solid State KCl | None | Store Dry |
| E8198 | Solid State NaCl | None | Store Dry |
| 4001 | Flow Cell | 3M KCl/Sat AgCl | Store Dry |
| 5094 | Flow Plus | 1M KCl | Empty & Store Dry |
| 9999 | Cathodic Protection | None | 3M KCl |
| A3135 | Gel Filled Ag/AgCl | None | 3M KCl/Sat AgCl |
| E8200 | Cathodic Disbondment Ag/Cl | Sat KCl w/ Ag/Cl | 3M KCl w/ Ag/AgCl |
| E8201 | Cathodic Disbondment Calomel | 3M KCl | 3M KCl |
| S2K222/333REF | Replacement Reference Electrode | None | None (Replace Cap) |
* The outer chamber of a Double Junction Refeence Electrode is filled with a solution that is inert to the ISE being used and is
normally between 0.1 Molar and 3 Molar. These probes are supplied with 1M NaNO3.
Filling Solutions:
Saturated KCl Filling Solution is for use with Calomel reference electrodes. They should be used when the reference electrolyte level falls below half way; this should be done using a disposable pipette. For reference electrodes that are based on and Ag/AgCl system please use product E8067 which is saturated with silver ions.
The solution is supplied in a leak-proof bottle with an inner liner to prevent creeping of the KCl. This product is also suitable for use as an outer bridge filling solution for ISE work with Calcium and Fluoride ISEs or other species where Potassium and Chloride do not interfere. The Saturated KCl Filling Solutions are listed below:
E8064 – 3 Molar KCl (100ml)
E8122 – 3 Molar KCl (500ml)
3 Molar KCl with Silver/SilverChloride Solution is for reference and combination pH electrodes based on Ag/AgCl. i.e. non Calomel reference electrodes. It is for use when the reference electrolyte level falls below half way and should be refilled using a disposable pipette.
This filling solution is compatible with all EDT combination pH electrodes. It is supplied in a 100ml leak-proof bottle with an inner liner to prevent creeping of the KCl. This filling solution is listed below:
E8067 – 3 Molar KCl Saturated with Ag/AgCl
Please note: these Reference Electrodes are Half Cells and require a sensor electrode to make a measuring circuit.
If you need further assistance with the storage & maintenance of your electrode please contact us here: [email protected]
More Articles On Reference Electrodes:
Which Reference Electrode Should I Use?
It is important to know which reference electrode to use for your application. Using the wrong electrode can ruin your results. In this article we will guide you through which electrodes are suitable for each application & Half Cell.
Operating Your Reference Electrode
Reference electrodes are to be used in conjunction with another half cell. these can be: pH, Ion Selective and REDOX Electrodes. This guide should help you understand how to get the best results from your electrodes.
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