In this article we learn about Types Of Resistance. In this article types of resistance classify according construction of resistance materials.
(1) Carbon Composition Resistors
It is a mixture of carbon particles and a binding resin with different proportions for providing desired resistance.
Attached to the ends of the resistive element are metal caps which have axial leads of tinned copper wire for soldering the resistor into a circuit.
The resistor is enclosed during a plastic case to stop the entry of moisture and other harmful elements from outside. Billions of carbon composition resistors are utilized in the electronic industry per annum .
They are available in power ratings of 1/8, 1/4, 1/2, 1 and 2 W, in voltage ratings of 250, 350 and 500 V.
They have low failure rates when properly used. Such resistors have a bent to supply electric noise thanks to the present passing from one carbon particle to a different .
This noise appears within the sort of a hiss during a loudspeaker connected to a hi-fi system and may overcome very weak signals.
That is why carbon composition resistors are used where performance requirements aren't demanding and where low cost within the main consideration.
Hence, they're extensively utilized in entertainment electronics although better resistors are utilized in critical circuits.
Attached to the ends of the resistive element are metal caps which have axial leads of tinned copper wire for soldering the resistor into a circuit.
The resistor is enclosed during a plastic case to stop the entry of moisture and other harmful elements from outside. Billions of carbon composition resistors are utilized in the electronic industry per annum .
They are available in power ratings of 1/8, 1/4, 1/2, 1 and 2 W, in voltage ratings of 250, 350 and 500 V.
They have low failure rates when properly used. Such resistors have a bent to supply electric noise thanks to the present passing from one carbon particle to a different .
This noise appears within the sort of a hiss during a loudspeaker connected to a hi-fi system and may overcome very weak signals.
That is why carbon composition resistors are used where performance requirements aren't demanding and where low cost within the main consideration.
Hence, they're extensively utilized in entertainment electronics although better resistors are utilized in critical circuits.
(2) Deposited Carbon Resistors
Deposited carbon resistors contains ceramic rods which have a carbon film deposited on them.
They are made by placing a ceramic rod during a methane-filled flask and heating it until, by a gas cracking process, a carbon film is deposited on them.
A helix-grinding process forms the resistive path. As compared to carbon composition resistors, these resistors offer a serious improvement in lower current noise and in closer tolerance.
These resistors are being replaced by metal film and metal glaze resistors.
They are made by placing a ceramic rod during a methane-filled flask and heating it until, by a gas cracking process, a carbon film is deposited on them.
A helix-grinding process forms the resistive path. As compared to carbon composition resistors, these resistors offer a serious improvement in lower current noise and in closer tolerance.
These resistors are being replaced by metal film and metal glaze resistors.
(3) High-Voltage Ink Film Resistors
These resistors contains a ceramic base on which a special resistive ink is laid down during a helical band.
These resistors are capable of withstanding high voltages and find extensive use in cathode-ray circuits, in radar and in medical electronics.
Their resistances range from 1 kΩ to 100,000 MΩ with voltage range upto 1000 kV.
These resistors are capable of withstanding high voltages and find extensive use in cathode-ray circuits, in radar and in medical electronics.
Their resistances range from 1 kΩ to 100,000 MΩ with voltage range upto 1000 kV.
(4) Metal Film Resistors
Metal film resistors are made by depositing vaporized metal in vacuum on a ceramic-core rod.
The resistive path is helix-ground as within the case of deposited carbon resistors.
Metal film resistors have excellent tolerance and temperature coefficient and are extremely reliable.
Hence, they're very suitable for varied high grade applications as in low-level stages of certain instruments although they're far more costlier.
The resistive path is helix-ground as within the case of deposited carbon resistors.
Metal film resistors have excellent tolerance and temperature coefficient and are extremely reliable.
Hence, they're very suitable for varied high grade applications as in low-level stages of certain instruments although they're far more costlier.
(5) Metal Glaze Resistors
A metal glaze resistor consists of a metal glass mixture which is applied as a thick film to a ceramic substrate then fired to make a movie .
The value of resistance depends on the quantity of metal within the mixture.
With helix-grinding, the resistance are often made to vary from 1 Ω to several mega ohms.
Another category of metal glaze resistors consists of a tinned oxide film on a glass substrate.
The value of resistance depends on the quantity of metal within the mixture.
With helix-grinding, the resistance are often made to vary from 1 Ω to several mega ohms.
Another category of metal glaze resistors consists of a tinned oxide film on a glass substrate.
(6) Wire-wound Resistors
Wire-wound resistors are different from all other types within the sense that no film or resistive coating is employed in their construction.
They contains a ceramic-core wound with a drawn wire having accurately-controlled characteristics.
Different wire alloys are used for providing different resistance ranges. These resistors have highest stability and highest power rating.
Because of their bulk, high-power ratings and high cost, they're not suitable for low-cost or high-density, limited-space applications.
The completed wire-wound resistor is coated with an insulate like baked enamel.
They contains a ceramic-core wound with a drawn wire having accurately-controlled characteristics.
Different wire alloys are used for providing different resistance ranges. These resistors have highest stability and highest power rating.
Because of their bulk, high-power ratings and high cost, they're not suitable for low-cost or high-density, limited-space applications.
The completed wire-wound resistor is coated with an insulate like baked enamel.
(7) Cermet (Ceramic Metal) Resistors
The cermet resistors are made by firing certain metals blended with ceramics on a ceramic substrate.
The value of resistance depends on the sort of mix and its thickness. These resistors have very accurate resistance values and show high stability even under extreme temperatures.
Usually, they're produced as small rectangles having leads for being attached to computer circuit boards (PCB).
The value of resistance depends on the sort of mix and its thickness. These resistors have very accurate resistance values and show high stability even under extreme temperatures.
Usually, they're produced as small rectangles having leads for being attached to computer circuit boards (PCB).