At one time, Hydro’s Ellenville plant was the leading American supplier of the connectors used to join power line cables together, supplying millions of connectors to the electrical utility industry annually. As those connectors, like other components in the system, may be nearing the end of their design life, Hydro is again part of the solution.
Complicating the problem is the increasing demand for electrical power to run air conditioning and all the modern electronic devices in our homes and offices. To meet this demand, power companies are increasing the amount of current that runs through the power grid. This increased current raises the temperature of the power lines and its various components by a significant amount.
Normal operating temperature along the grid was about 120° F (49° C). The extruded aluminum connectors used in most of the grid were designed to operate at temperatures up to about 160° F (71° C). With the increased current, the power grid is now operating at temperatures ranging from 194° F to 212° F (90° C – 100° C). At temperatures above 199° F (93° C), the aluminum connectors begin to anneal due to the heat. As a result the connectors become weaker which increases the likelihood of failure.
Identifying and replacing connectors before they fail
Power companies use infrared imaging to identify which connectors are overheating so they can be replaced. Instead of the traditional replacement connector, such as the one Hydro’s Ellenville plant manufactured, Classic Connectors, Inc. of Clinton, Ohio, has developed a patented shunt-type connector that is stronger than the traditional design and can handle the higher current passing through the power grid. The product includes an extruded aluminum rail supplied by Hydro.
According to Classic Connectors, the cost for the traditional method to replace a single connector can run from $6,400 to as high as $15,000 with the average cost ranging from $7,000 to $8,000. Using the new ClampStarTM from Classic Connectors, a power company can reduce that cost by half, with the repair completed in less than one-third of the time it takes using the old solution. The potential savings for the power companies is huge so it’s no surprise they are taking a careful look at the ClampStarTM.
Meeting connector standards
One of the issues any time a new product is introduced into a sensitive system such as the power grid, is the ability of the new solution to meet industry standards through a rigorous testing process.
ClampStar has been tested to withstand cable temperatures as high as 635° F (335° C) by independent laboratories using a 500 cycle method over three months. At peak temperatures above 700° F (371° C), the ClampStarTM connector rails were running at temperatures in the 150° F to 160° F (66° C – 71° C) range, well below the 199° F (93° C) temperature that starts causing annealing.
The ClampStar connector meets ANSI standard C119.4AA and is the only solution that meets the new proposed standard C119.7 Class HT-AA. These standards set the requirements for transmission line connectors.
Hydro supplies critical rail component
ClampStar’s rigid rail model includes an extruded component that can be used in most transmission line connections. Hydro’s Belton operations extrude the rail component and deliver them to Classic Connectors assembly plant in Ohio. Hydro will also be supplying the roll stock used in making ClampStar’s flexible model Correctors, which are primarily used for splices, clamps and other connectors: including bolted and compression deadends, on HV, EHV and UHV transmission lines.
