Ceramic Resistor Construction

This mixture is then compressed into a cylindrical shape.

Ceramic resistor construction.

Wirewound resistors are very variable in construction and physical appearance. The resistance is controlled based on the ratio of the insulator and conductor mixture. The ceramic coating combines a high insulation and physical protection with good heat dissipation. The construction of ceramic composition resistors concentrates nearly all of the component mass into the resistive element resulting in a rugged device with high energy capacity.

Terminals are attached and the insulation coating is applied to the outside. The resistor is made by taking an alumina or ceramic substrate. Typical resistance values are in the range from 1ω til 10 kω. The majority of the power wirewound resistors have a ceramic core and a ceramic coating to protect the winding.

Their resistive elements are commonly lengths of wire usually an alloy such as nichrome nickel chromium or manganin copper nickel manganese wrapped around a ceramic or glass fibre rod or tube and coated in an insulating flameproof cement film. However even this description is out of date. The construction of a carbon film resistor can be done by placing the carbon layer on a substrate of a ceramic. This resistor consists of two terminals like a normal resistor.

Tcr varies from 75 till 200 ppm c. Composition resistors are produced using a mixture of a finely ground insulator and conductor. Metal film resistors are produced by depositing a resistive element on a high grade ceramic rod. Then a thin film of resistive material is deposited this is typically metal oxide or a metal film again the resistor is fired.

The carbon film is a resistive material toward the flow of current in this resistor. It is a nickname for the heat resistant ceramic case in which a coil of resistance wire is potted. The end connection electrode bases are then placed onto this and then this is fired to ensure they are robustly held in place.