Our Model UC concentric coupon is designed to make potential measurements that are substantially free of IR-drop error without either interrupting current or disconnecting the coupon. The potential measuring port is located in the center of the coupon, well away from IR drop fields in the environment. Concentric coupons are preferred for locations where interrupting currents or disconnecting the coupon to make measurements is not practical. They are particularly well suited for use with remote monitoring units.
EDI’s concentric CP coupon is typically installed at the base of a test station since access through a soil tube is needed 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 and a 1 sq. cm. coupon for measuring AC current density.
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Through-wall reference electrodes are used for measuring corrosion potential on the inside of condenser waterboxes, circulating pipes, tanks and vessels. These electrodes are installed by threading into a tapped hole on the wall; a junction box is typically attached to the other end to protect the wiring connections. Through-wall reference electrodes can be ordered with any commonly used sensing element.
The Heavy Duty Probe (Model FH) has a glass reinforced epoxy (G-10 GRE) extension tube and a 316L stainless steel nipple. It can be used at pressures up to 75 psi (0.5 MPa) and intermittent temperatures up to 210ºF (98ºC). Model FH is available in three size variations: Model FH10 is threaded into a 1 inch NPT hole, Model FH7 is threaded into a 3/4 inch NPT hole, Model FH5 is threaded into a 1/2 inch NPT hole; all three variations have a 1 inch NPT thread on the termination side.
The temperature limits stated are those for the wetted materials of construction. Through-wall reference electrodes should generally not be continuously used at temperatures exceeding 110ºF (45ºC) because the reference potential will be significantly different from its value at ambient temperature and the electrode service life will be drastically shortened. The product will survive occasional brief temperature excursions up to the limits stated in the preceding paragraph. For applications involving continuous exposure to temperatures over 110ºF (45ºC), our Model FE Process Vessel Reference Electrode is recommended.
The Model AT Linear Modular Anode System is an impressed current linear anode system which permits maximum design flexibility. It consists of a copper cored titanium flat wire coated with mixed metal oxide and attached to a #14 AWG HMW/PE insulated bus wire. The wire pair is surrounded by a flexible plastic mesh. Individual anodes are 50 ft. long and are easily connected in the field to form a hermetically sealed joint. This flexibility allows the design engineer to choose a layout which is best suited for the application.
Perhaps the most significant feature of the Model AT is its unique connector system. Each anode is supplied with a pin connector on one end and a socket connector on the opposite end which can be mated either to another anode section to form a string or to a power feed cable. Specially developed “tee” connectors allow intermediate current feeds on long strings. No splicing or welding is required in the field so installation can be completed in substantially less time than any other system. For example, it takes less than 6 man-hr. to install this anode system in a 60 ft diameter tank.
The Immersion Reference Electrode, Model IR, is designed for long term installation in an aqueous environment. Typical applications include elevated water tanks, standpipes, ground storage tanks, clarifiers, traveling screens, trash racks, submerged pipelines, locks, dams, and dock structures. The electrode can be directly suspended by its lead wire, cemented directly to 3/4 inch PVC conduit using the optional socket end termination, or securely attached to a steel structure with the optional magnetic mount. Antifreeze protection is also available for those situations where the electrode may be exposed to temperatures down to -30°F (-34°C). However, antifreeze may shift the reference potential by up to 12 mV.
The Model IR has a twenty year design life and uses #12 AWG RHW/USE lead wire. This electrode can also be fitted with a concentric cathodic protection coupon which minimizes voltage drop error in potential measurements (Model IRC). Another option is a copper sleeve which will reduce biofouling when the electrode is exposed for extended times in natural seawater (Model IRF). Potable water applications requiring NSF61 certification should use Model IRW.
Model IR can be used in all aqueous environments. For clean full strength seawater applications, our Model IP-AGDImmersion Reference may be a more economical alternative.