2018 Product Catalog

4 MELTRIC PRODUCT FEATURES... Spring-Loaded Butt Contacts MELTRIC products feature spring-loaded, butt contacts simi- lar to those used in contactors and switchgear. These contacts have numerous advantages, which help improve electri- cal performance and user safety relative to pin and sleeve contacts or the arcuate contacts used in twist-type devices. Butt-style contacts ensure a very positive and consistent connection. The spring-loading of these contacts, which is accomplished with coil springs, provides a desirably high contact force that remains constant over thousands of operations. In addition, it automatically compensates for any wear and/or deviations in contact length resulting from man- ufacturing tolerances. This is a critical point, as contact force is a key determinant of the quality of a contact. As the accompanying chart demon- strates, contact resistance increases as contact force is reduced. Higher contact resistance generates more heat and oxidation, both of which contribute to the deterioration of the contact. This is a problem with pin and sleeve and arcuate type contacts because their contact force varies with manufacturing tolerances and is reduced due to wear that occurs with normal use. Most MELTRIC contacts close with a self-cleaning wiping ac- tion. When the contacts initially mate, they are slightly offset. In completing the connection, the plug contacts are rotated across the receptacle contacts, helping to remove deposits from the contact surfaces. In conjunction with the spring-loaded casings used on many MELTRIC products, the spring-loaded contacts ensure a quick breaking of the connection that is independent of the motion of the user. By contrast, the disconnection speed of pin and sleeve and twist-type devices is dependent upon the motion of the user. MELTRIC 0 10 20 30 40 50 60 70 60 50 40 30 20 10 Other guys Contact Pressure (Force) Contact Resistance