Ceramic Resistor Construction

The construction of a resistor is shown in the below diagram.

Ceramic resistor construction. 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. The end connection electrode bases are then placed onto this and then this is fired to ensure they are robustly held in place. This mixture is then compressed into a cylindrical shape.

They are most often wire wound resistors. However even this description is out of date. This resistor consists of two terminals like a normal resistor. It is a nickname for the heat resistant ceramic case in which a coil of resistance wire is potted.

Tcr varies from 75 till 200 ppm c. Composition resistors are produced using a mixture of a finely ground insulator and conductor. The construction of a carbon film resistor can be done by placing the carbon layer on a substrate of a ceramic. 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.

Typical resistance values are in the range from 1ω til 10 kω. 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. Wirewound resistors are very variable in construction and physical appearance.

The resistor is made by taking an alumina or ceramic substrate. Cement resistor only describes the appearance of common power resistors like that shown above. Terminals are attached and the insulation coating is applied to the outside.