All About Fixed Resistor

                 All About Fixed Resistor 

• The resistors made up of ceramic body and are cylindrical in shape with definite resistance values are fixed resistors. 

• The resistive element could be either carbon film, thick film or a wound wire element. 

• The properties of fixed resistors depend upon the type of fixed resistor used. 

• A carbon film resistor has 5% tolerance, power rating of 0.125 W­ 2 W, Temperature co­efficient of 250­450ppm/k. 

• A metal film resistor has 1% tolerance, power rating of 0.1­5W and Temperature co­efficient of 10­250ppm/K. 

• A wire wound resistor has 1% tolerance, power rating of 1­200W and Temperature co­efficient of 20­400ppm/K. 

 Types of Fixed Resistor

Based on the type of material used in constructing a resistor it is classified into:  Carbon composition, carbon pile, carbon film, metal film and metal oxide film. 

Carbon Composition is made up of carbon clay composition with plastic coating around it. 

Carbon Pile is made up of a stack of carbon disks compressed between two metal contact. 

Carbon film is deposited on an insulating substrate and cut into thin resistive path. 

Metal Film is cylindrically shaped and coated with Nickel Chromium. 

Metal Oxide Film is made up of tin oxide. 

• Application of Fixed Resistors: The applications of Fixed Resistors are:

1. Protecting other components from damage due to excess current. 
2. Dividing voltage to different parts of the circuit. 
3. Timing applications where a fixed resistor is used along with a capacitor to control time delay.