Electrochemical Devices Inc. logo

Electrochemical Devices Inc.

Corrosion Control Products, Including Reference Electrodes, Cathodic Protection Coupons, Impressed Current Anodes, 

About Electrochemical Devices Inc (EDI)

Electrochemical Devices Inc (EDI) manufactures products for monitoring and preventing corrosion. They proudly manufacture all their products in the USA.

EDI Product Features:

  • Designed specifically for engineers responsible for controlling corrosion
  • Easy-to-Install
  • Longest Service Life in the Industry

Underground Reference Electrodes

A collection of products designed especially for underground use. This includes standard design, reduced diameter design, as well as reference electrodes specific to under tank use. Included in this group of products are cathodic protection coupons with or without magnetic switches.
Reference Electrode, contained in a cotton bag filled with bentonite-gypsum backfill
Simplifies installation of permanent underground electrodes in congested locations. Great for use beneath aboveground storage tanks and between closely-spaced underground storage tanks.
A Reference Electrode designed to last, even when installed underneath an AST, a location where dry sand, heat and cathodic protection currents wear out most other reference electrodes
When potential measurements are needed, the electrode is pulled through the pipe installed beneath the tank.
EDI Cathodic Protection Coupons
CP Coupons permit the measurement of IR drop free potentials on all types of underground cathodic protection systems.

Also called standard design underground reference electrodes, these are the original reference electrode design for permanent underground applications. Known for proven, long-term durability. Contained in a cotton bag, filled with bentonite-gypsum backfill.

These electrodes were developed to simplify the installation of permanent underground electrodes in congested locations. They can be installed in a 5 cm (2 inch) diameter bore hole which makes them ideal for retrofit installations beneath paved surfaces. Alternate applications are beneath aboveground storage tanks and between closely spaced underground storage tanks.

These electrodes are placed in a slotted pipe installed in the sand pad beneath an aboveground storage tank bottom. When tank bottom potentials are needed, the electrode is slowly pulled through the pipe to produce a potential profile.

CP Coupons permit the measurement of IR drop free potentials on all types of underground cathodic protection systems (sacrificial and impressed current).

Impressed Current Anodes

Impressed current anodes are available with platinum or mixed metal oxide surfaces and titanium or niobium substrates, either solid or copper-cored.
3 modular linear anodes, showing unique connector
Aqueous Anode Model AR12
Modular Linear Anode System is a linear distributed anode system consisting of a MMO anode wire periodically connected to a larger bus wire. It is modular in design with a unique connector system that permits easy field installation in any desired configuration. Primary applications include beneath aboveground storage tanks or alongside pipelines. It can also be used in other underground and aqueous applications where a linear distributed anode is required
Probe Anodes have a threaded stainless steel nipple mount and are commonly used in power plant waterboxes. Available rod diameters are 3/8 inch, 1/2 inch and 3/4 inch. Standoff and active lengths usually range from 1 inch to 9 inches.

Allied Corrosion Industries works with design and corrosion engineers to produce impressed current anodes for those applications where our standard models may require modification. We do not charge design fees for this service and in most cases the custom product is priced comparably to a similar standard product

Allied Corrosion Industries can restore virtually any probe anode to new specifications for about half the cost of purchasing a new anode. Contact us for details.

Importance of Backfill

The backfill surrounding a bagged reference electrode is a mix of gypsum and bentonite. The primary purpose of backfill is to retain water which ensures that a low contact resistance between the electrode and the surrounding earth is maintained. Additionally, backfill usually prevents the inner core of the electrode which contains a saturated salt gel from drying out. During severely dry conditions, the electrode may dry out. The backfill will rewet with local groundwater, and the electrode should re-activate. However, local ground water will have many other chemicals dissolved in it that can affect the accuracy of the electrode. If this situation is suspected, the electrode should be calibrated against a reference electrode of known accuracy to determine whether replacement is necessary.

Design Life

The design life of a reference electrode is an estimate of the time based on test results it would take for enough salt to diffuse out from the inner core to lower the salt concentration to below saturation. At EDI, we use several techniques to extend this time as much as possible. One of these techniques is to increase the amount of salt reserve contained in the gel. This is one reason why longer life electrodes have physically bigger housings.

Potential Measurements Beneath ASTs

The environmental conditions beneath an aboveground storage tank make it very difficult to obtain potential measurements. The sand is dry when the electrode is first installed. Cathodic protection currents and/or heat from the product further dries out the sand sharply increasing resistivity. A permanently installed reference electrode can completely dry out in this environment and the absence of moisture in the area will prevent it from rewetting. Consequently, electrodes in such locations may last only a few years. That may be sufficient time, however, for commissioning and testing a cathodic protection system. Where potential measurements throughout the life of an AST are desired, use our Undertank Reference Electrode (Model UT).