June Featured Product of the Month Model SM Magnetic Switch

EDI Model SM Magnetic Switch System consists of a sealed reed switch for use in above and below ground test stations. The switch is activated by holding a magnet next to the colored band. Green bands denote normally closed switches which are momentarily opened with the magnet. These are most often used for instant-disconnect cathodic protection coupon measurements. Red bands denote normally open switches which are momentarily closed with the magnet. These can be used to electrically isolate a reference electrode in test stations which may become submerged.Magnetic switches are available in Board Mount, Model SM-BRD, or Adjustable Mount, Model SM-ADJ, configurations. are on a small circuit board with two 9/32 in. (7 mm) dia. holes on 1 in. (25.4 mm) spacing. These switches will fit over adjacent terminals of most test stations.  are centered on a length of wire terminating in 9/32 in. (7 mm) ID ring lugs. Ring lugs are spaced at 6-1/4 in. (160 mm). This design is used when the switch must span non-adjacent terminals in a test station. 
An activating magnet with a lanyard, Model SM-MAG, is recommended for use with the switches.
Electrical Specifications
Switching Current: 0.5 amps
Carry current: 1.0 amp
Switching Voltage: 175 volts
Breakdown voltage: min. 200 VDC
Contact resistance: 150 µohm
Operating temp.: -40F – 260F (-40C – 130C)

April Featured Product of the Month Model IT

EDI’s permanent portable reference electrode, Model IT, is used to make potential readings in any application where a standard, liquid-junction portable reference electrode is presently being used. The Model IT contains a gel rather than a liquid so it can be used in all positions. The gel provides long maintenance-free service since it does not require refilling or cleaning. Soil contact is through a hardwood plug which offers several advantages over ceramic membranes: it will not clog as readily, it is resistant to salt blockage, and it can be reworked by light sanding or cutting if it becomes contaminated with oil. The Model IT has a twenty year design life and an indefinite shelf life if the end cap is in place. Gelled copper/copper sulfate (CUG) electrodes have a blue housing while gelled silver/silver chloride (AGG) electrodes have a light grey housing. Both models have a 1/4 – 20 threaded stud termination.

March Featured Product of the Month Model CB

A typical rebar monitoring system consists of a rebar probe, such as Model CP-REB, installed the same distance below the surface as the rebar being monitored.   It is used in conjunction with an Ag/AgCl reference electrode such as the Model CB-AGG for linear polarization resistance measurements of corrosion rate. In this application, the rebar probe is the working electrode while the rebar net is the counter electrode. By periodically monitoring corrosion rate, the efficacy of sealers, membranes and inhibitors can be verified.  Installation of probes is made easier by using a framework such as our Model CR1 rebar frame shown above. The probe and reference electrode are attached to the rebar frame in advance and the entire assembly is tack welded to a structural rebar.   In addition to simplifying installation, the use of the Model CR1 rebar frame ensures that the relative placement of the probe and reference electrode is identical at every installation site.

February Featured Product of the Month Model UC

Our concentric coupon, Model UC, is designed to make potential measurements that are substantially free of IR-drop error without either interrupting current or disconnecting the coupon. It is known as a Concentric CP coupon because the potential measuring ports are located in the center of the coupon, well away from IR drop fields in the environment. This design is preferred for locations where interrupting currents or disconnecting the coupon to make measurements is not practical. It is particularly well suited for use with remote monitoring units. EDI’s concentric CP coupon may be installed at the base of a test station where access through a soil tube is used for making potential measurements. This product may also be ordered with a contained packaged zinc reference electrode which eliminates the need for access through a soil tube. Either version can be ordered with a 1 sq. cm. coupon for measuring AC current density.

 

 

 

 

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January Featured Product Model UT

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. Where potential measurements throughout the life of an AST are desired, a preferred solution is to use our Undertank Reference Electrode (Model UT).

The Undertank Reference Electrode is placed in a slotted pipe installed in the sand pad beneath the tank bottom. When bottom potential measurements are needed, the electrode is slowly pulled through the pipe to produce a potential profile. An alternate design with a threaded coupling rather than an eye-bolt can be used in those cases where it is necessary to push the electrode into the pipe. Between measurements, the electrode can be either left at one end of the slotted pipe or used to develop a potential profile in another tank.

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December Featured Product Model FE

The Model FE Process Vessel Reference Electrode is designed to operate in environments where ordinary reference electrodes cannot survive. These include elevated temperatures, high pressures and/or contaminated electrolytes. This is a two-piece unit consisting of a bridge which is permanently installed at each location where potential measurements are desired and a separate reference electrode. Because the reference electrode is a separate piece, it is isolated it from the aggressive environment which substantially increases its service life. The reference electrode can also be removed for calibration or service without affecting the integrity of the vessel.

For intermittent readings, the reference electrode is simply pressed into the bridge. In this case, a single reference can be used with several bridges. When continuous readings are required, the reference electrode is threaded into the bridge. Reference elements available with this product are gelled copper/copper sulfate or gelled silver/silver chloride. You will find more data here Model FE

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EDI CEO, Jim Diamond will be guest speaker

Jim Dimond, President of Electrochemical Devices, Inc., will address the Western New York corrosion committee on Thursday December 13th at 10 AM. The meeting will be held at:

Leisure’s Restaurant
6001 Big Tree Road
Lakeville, NY 14480
WebSite: http://www.leisuresrestaurant.com/

Title: Coupon Technology – An Overview

Jim will address the reason for using, where to use, and where to not use Cathodic Protection Coupons. He will discuss installation procedures as well as proper interpretation of data collected from Cathodic Protection Coupons. He will explain advantages of the Concentric Coupon with emphasis on the elimination of an IR component even where there are local current sources. He will explain interrupting CP current with a magnetic switch.

Prior to becoming President of EDI, Jim was president of Dimondale Co. Inc. which designs and manufactures cathodic protection products. Previously, he oversaw reference electrode manufacturing for Harco, Inc. He has over 40 years’ experience in cathodic protection including product design, manufacturing, and field engineering.

Electrochemical Devices, Inc. (EDI) was founded in 1986 and specializes in the design and manufacture of a variety of products for monitoring and controlling corrosion, including cathodic protection coupons. They provide the concentric coupon and a magnetically operated switch to connect the coupon and structure.

TN 1 How to measure tube sheet potentials

The potential across a tubesheet under cathodic  protection can show large variations from one location to another. Different waterboxes of the same apparent design can produce different potential distributions. Areas with excessively electronegative potentials can cause hydrogen damage to titanium or ferritic stainless steel tubes. Other areas may have potentials insufficiently negative to adequately protect the copper alloy tubesheet. These potential gradients cannot be detected by a reference electrode mounted on the side wall of the waterbox.

EDI’s Model TE Tubesheet Mounted Reference Electrode is designed to mount any place on the face of a tubesheet. They are shipped with a double tube plug which is inserted into the end of a condenser tube and tightened. Tube plugs are available for common tube sizes between 5/8 inch and 1-1/4 inch. The electrode’s lead wire terminates in a waterproof connector which plugs into a mating connector on the Model TW wire which has been affixed to the tube sheet face.  This attachment system allows the electrode to be easily removed during scheduled outages.  For additional information, visit EDI website.

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November Featured Product Model TE

The potential across a tubesheet under cathodic protection can show large variations from one location to another. Areas with excessively electronegative potentials can cause hydrogen damage to titanium or ferritic stainless steel tubes. Other areas may have potentials insufficiently negative to adequately protect the tubesheet. These potential gradients cannot be detected by a reference electrode mounted on the side wall of the waterbox. EDI’s Model TE Tubesheet Mounted Reference Electrode is designed to mount any place on the face of a tubesheet. They are shipped with a double tube plug which is inserted into the end of a condenser tube and tightened. The electrode’s lead wire terminates in a waterproof connector which plugs into a mating connector on the lead wire which has been affixed to the tube sheet face. This attachment system allows the electrode to be easily removed during scheduled outages. You will find more info here Model TE

October Featured Product Model CM

Our Model CM reference electrode can be used in all types of concrete structures. When this electrode is used in seawater applications, where the chloride level of the pore water is expected to remain nearly constant, it functions as a reference electrode providing stable reproducible potential readings. When used in other structures in which the chloride level can vary slowly over time, Model CM provides short term stability suitable for depolarization measurements. Its small size makes it suitable for embedding in the grouted annular space behind piling wraps.
You will find more data here Model CM

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