Cermet preset potentiometers

 Preset potentiometers are are variable resistors. The resistance value can be varied using a screwdriver to turn the screw mechanism on the device. Cermet is a combination of ceramic and metal used in several applications including the manufacture of resistors, especially potentiometers. Metal provides ability to undergo plastic deformation while ceramic provides hardness and high temperature resistance. Metallic elements usually used in cermet are nickel, molybdenum, and cobalt. Marking 50 3 indicates a resistance value of 50 Kilo Ohms. Number three meaning 10 to the power of 3.



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