All Stories
Showing posts with label Electric Cables. Show all posts
Showing posts with label Electric Cables. Show all posts

Friday, October 4, 2013
Varnished Cambric Insulated Electric Cables
The cambric efficiently dried and treated with suitable insulating varnish with a liberal surface coating has been used to hard. Now this surface becomes a flexible and smooth. The varnished cambric insulation is prepared to dip the cotton into together. Varnished is prepared by oil and petroleum jolly rall layers of varnish is applied to the conductor in the form of taps, if required, the cable is also lead-covered and braid and finally suitably compounded. We know that the moisture is affected on the able; therefore the outer cover of petroleum jolly is laid on the insulation. 

Varnished Cambric Insulated Electric Cables




Varnished Cambric Insulated Electric Cables
The cambric efficiently dried and treated with suitable insulating varnish with a liberal surface coating has been used to hard. Now this surface becomes a flexible and smooth. The varnished cambric insulation is prepared to dip the cotton into together. Varnished is prepared by oil and petroleum jolly rall layers of varnish is applied to the conductor in the form of taps, if required, the cable is also lead-covered and braid and finally suitably compounded. We know that the moisture is affected on the able; therefore the outer cover of petroleum jolly is laid on the insulation. 

5 comments
Posted at 7:25 AM |  by Unknown
Impregnated paper insulation electric cables 
Due to increasing cost of rubber, another form of insulation is introduced. After many experiments a conductor insulated with paper or jute were introduced. The paper or jute being impregnated with a suitable compound, The paper insulation is laid on to the conductors in the form of paper taps, which is laid helically to the desired thickness to achieve a required dielectric strength. The copper conductors, lapped with layers of paper impregnated with a good insulating compound. The impregnated paper consist of felted matt of long fibers. Washing  of the both at the pulps stage and after formation of the sheet fibers, is an important. Because due to this factor the properties of the paper for cables can be controlled.
At one time manila was recognized as the best paper cable insulation. But today, the chemical wood-pulp sulphate is generally used. The paper insulation is laid on to the conductors and then being vacuum dried. After drying the other suitable compound. A two-core cable, the insulated cores of a cable is laid up together with a packing of jute or paper to give a circular formation. If the cable lras three, four or more cores, each core is prepared separately and generally laid up with an overall layer of paper. All cables ends are sealed by special compound muct be free from moisture. For this purpose the conductors or cores are placing in a heated chamber that can be reduced to a vacuum. The value  of temperature and heating time is depending upon the type of cable.
This drying process is followed by impregnation of the cable with suitable insulating oil or compound. In these cables, if greater mechanical protection is to be provided, the steel armoring is usually applied over a over a bed of jute or layer of tape. The purpose of the metallic shielding tape around a cable is to control the electro static stress and decrease the thermal resistance of cable. A sheath of lead provides the necessary protection. A sheath of bitumen compound has been used successfully. Although vulcanized bitumen has the advantage of being light and flexible, after laid on paper insulation on conductor, a cotton of potson contained red led compound core is also laid on the cable.
The disadvantage of impregnated paper insulation cable i that whenever joints are made to other cables an efficient sealing i essential.

Impregnated Paper Insulation Electric Cables

Impregnated paper insulation electric cables 
Due to increasing cost of rubber, another form of insulation is introduced. After many experiments a conductor insulated with paper or jute were introduced. The paper or jute being impregnated with a suitable compound, The paper insulation is laid on to the conductors in the form of paper taps, which is laid helically to the desired thickness to achieve a required dielectric strength. The copper conductors, lapped with layers of paper impregnated with a good insulating compound. The impregnated paper consist of felted matt of long fibers. Washing  of the both at the pulps stage and after formation of the sheet fibers, is an important. Because due to this factor the properties of the paper for cables can be controlled.
At one time manila was recognized as the best paper cable insulation. But today, the chemical wood-pulp sulphate is generally used. The paper insulation is laid on to the conductors and then being vacuum dried. After drying the other suitable compound. A two-core cable, the insulated cores of a cable is laid up together with a packing of jute or paper to give a circular formation. If the cable lras three, four or more cores, each core is prepared separately and generally laid up with an overall layer of paper. All cables ends are sealed by special compound muct be free from moisture. For this purpose the conductors or cores are placing in a heated chamber that can be reduced to a vacuum. The value  of temperature and heating time is depending upon the type of cable.
This drying process is followed by impregnation of the cable with suitable insulating oil or compound. In these cables, if greater mechanical protection is to be provided, the steel armoring is usually applied over a over a bed of jute or layer of tape. The purpose of the metallic shielding tape around a cable is to control the electro static stress and decrease the thermal resistance of cable. A sheath of lead provides the necessary protection. A sheath of bitumen compound has been used successfully. Although vulcanized bitumen has the advantage of being light and flexible, after laid on paper insulation on conductor, a cotton of potson contained red led compound core is also laid on the cable.
The disadvantage of impregnated paper insulation cable i that whenever joints are made to other cables an efficient sealing i essential.

No comments
Posted at 7:23 AM |  by Unknown
T.R.S or C.T.S electric cables
T.R.S or C.T.S electric cables
Tough rubber sheath (T.R.S) protection , first introduced by the St. Helens cable Co., under the name C.T.S (cab tyre sheath) is usually lapped on to the already insulated conductor. In tough rubber sheathed cable, the conductor is insulated with  vulcanized rubber insulation. T.R.S cables are manufactured in this way that the cables are with stand the mechanical damage. A hard rubber  cover is used to protect the cable from external damage effects. In this type of cables hard rubber or thermo plastic cover is used on single core, two core or three core V.R.I cables. This type of cable is commonly used in open  wiring system. The external sheath cover provides the mechanical protection not for electrical insulation to the cable. The diameter of sheath cover is 1/2 cm approximately.

Tough Rubber Sheath electric cables (T.R.S electric cables) or C.T.S electric cables

T.R.S or C.T.S electric cables
T.R.S or C.T.S electric cables
Tough rubber sheath (T.R.S) protection , first introduced by the St. Helens cable Co., under the name C.T.S (cab tyre sheath) is usually lapped on to the already insulated conductor. In tough rubber sheathed cable, the conductor is insulated with  vulcanized rubber insulation. T.R.S cables are manufactured in this way that the cables are with stand the mechanical damage. A hard rubber  cover is used to protect the cable from external damage effects. In this type of cables hard rubber or thermo plastic cover is used on single core, two core or three core V.R.I cables. This type of cable is commonly used in open  wiring system. The external sheath cover provides the mechanical protection not for electrical insulation to the cable. The diameter of sheath cover is 1/2 cm approximately.

7 comments
Posted at 7:21 AM |  by Unknown

V R I electric cables
Natural rubber is the coagulated latex of certain species of tress. Vulcanized rubber is posse's high insulating qualities, but the material absorbs moisture and deteriorates by rapidly oxidizing into a resinous substance. Therefore 3 to 5 % amount of sulphur is incorporated with the rubber; as a result, it becomes a imprevious to water, flexible and of high resistivity.
This whole process is known s vulcanization and the product which is obtained is known as vulcanization rubber. This process is performed at 149 degree c and which is above the melting point of sulphur. It has  a good mechanical strength, dependent upon its degree of vulcanization. When we use this type of cable in which place, where the heat and day light are not present, and the vulcanized rubber retains its physical properties for a long period.
It is found that, it has a high specific insulation resistance and elastic, which is not present as high as that of pure rubber.
The pure rubber is become soft when we use at high temperature, as a result in winter season it is hard and break down. Rubber has negative effects on copper conductor, therefore the copper conductors are tinned and then vulcanized rubber insulation is used.
To prevent the weather affects a cover is used on the cable insulation. This is known as braiding. The braiding is affected by passing the cable through a machine, which makes a very tight and neat covering. The braiding may be of cotton, jute, glace cotton, silk or even of steel, copper, or phosphor bronze wire.
The v.r.i cables are mostly use in surface and underground wiring system for domestic and industrial installation. The is composed of either natural or synthetic rubber mixed with modifying agents to gave it the desired mechanical and electrical properties.

Vulcanized Rubber insulated electric cables (V.R.I electric cables)


V R I electric cables
Natural rubber is the coagulated latex of certain species of tress. Vulcanized rubber is posse's high insulating qualities, but the material absorbs moisture and deteriorates by rapidly oxidizing into a resinous substance. Therefore 3 to 5 % amount of sulphur is incorporated with the rubber; as a result, it becomes a imprevious to water, flexible and of high resistivity.
This whole process is known s vulcanization and the product which is obtained is known as vulcanization rubber. This process is performed at 149 degree c and which is above the melting point of sulphur. It has  a good mechanical strength, dependent upon its degree of vulcanization. When we use this type of cable in which place, where the heat and day light are not present, and the vulcanized rubber retains its physical properties for a long period.
It is found that, it has a high specific insulation resistance and elastic, which is not present as high as that of pure rubber.
The pure rubber is become soft when we use at high temperature, as a result in winter season it is hard and break down. Rubber has negative effects on copper conductor, therefore the copper conductors are tinned and then vulcanized rubber insulation is used.
To prevent the weather affects a cover is used on the cable insulation. This is known as braiding. The braiding is affected by passing the cable through a machine, which makes a very tight and neat covering. The braiding may be of cotton, jute, glace cotton, silk or even of steel, copper, or phosphor bronze wire.
The v.r.i cables are mostly use in surface and underground wiring system for domestic and industrial installation. The is composed of either natural or synthetic rubber mixed with modifying agents to gave it the desired mechanical and electrical properties.

9 comments
Posted at 12:07 AM |  by Unknown
The construction of cable is that to envelope the conductor in a non-conducting material. The insulation is this material in which the electricity can not flow.
For cable insulation there are many insulation material are used such as P.V.C, mica, paper,, rubber etc.
The purpose of insulation is that to provide protection against electric shock, leakage of current and fire etc.
In the below table the insulation for conductors are listed.
"The materials used for wires and cable insulation are vulcanized rubber, varnished cloth, impregnated paper, vinyl plastics, polyethylene, cotton and silk etc.
table
(1) Vulcanized rubber insulated cable.
(2) T.R.S or cabe-tyre sheath cable.
(3) Impregnated paper insulation cable.
(4) Poly-vinyl-chloride cable.
(5) Varnish cambric insulted cable.
(6) Poly chloroprene cable.
(7) Armoured cable.

Classification of cable W.R.T insulation core, voltage grade and current carrying capacity with table

The construction of cable is that to envelope the conductor in a non-conducting material. The insulation is this material in which the electricity can not flow.
For cable insulation there are many insulation material are used such as P.V.C, mica, paper,, rubber etc.
The purpose of insulation is that to provide protection against electric shock, leakage of current and fire etc.
In the below table the insulation for conductors are listed.
"The materials used for wires and cable insulation are vulcanized rubber, varnished cloth, impregnated paper, vinyl plastics, polyethylene, cotton and silk etc.
table
(1) Vulcanized rubber insulated cable.
(2) T.R.S or cabe-tyre sheath cable.
(3) Impregnated paper insulation cable.
(4) Poly-vinyl-chloride cable.
(5) Varnish cambric insulted cable.
(6) Poly chloroprene cable.
(7) Armoured cable.

No comments
Posted at 12:05 AM |  by Unknown

Mechanical Factors on electric cables

The overall protective coverings of the cable, prevent the cable form moisture ingress, provide resistance to mechanical damage and also to other external influences such as corrosion and fire.
We know that the robber insulation tends to become softend sticky after long and continuous contact with oil or grease.
It  is applicated that the rubber insulation cables should not be exposed to the direct rays of sun, so therefore P.V.C insulated cables are use in these cases.
P.V.C insulation is un-affected by oil, grease, acids and chemical.
In case of P.V.C cables the risk of mechanical injury is reduced.

Mechanical Factors on electric cables


Mechanical Factors on electric cables

The overall protective coverings of the cable, prevent the cable form moisture ingress, provide resistance to mechanical damage and also to other external influences such as corrosion and fire.
We know that the robber insulation tends to become softend sticky after long and continuous contact with oil or grease.
It  is applicated that the rubber insulation cables should not be exposed to the direct rays of sun, so therefore P.V.C insulated cables are use in these cases.
P.V.C insulation is un-affected by oil, grease, acids and chemical.
In case of P.V.C cables the risk of mechanical injury is reduced.

4 comments
Posted at 12:04 AM |  by Unknown

Thursday, October 3, 2013

Affect's of Temperature on Electric cables


Temperature is also affected on the cable. To choose a cable, the temperature is a most important factor. We know that summer season the temperature is reduced, but in hotter conditions, the current carrying capacity of cables is decreased, when a current passing through the cable, heat is produced due to internal resistance of the conductor.
The maximum conductor  temperature of a P.V.C insulated cable is 70 degree centi  for continuous operations and 130 degree centi for short periods of time (4 hours).
This means that the maximum ambient temperature in which a P.V.C insulated cable cam be operated economically is about 65 degree centi.

Affect's of Temperature on Electric cables

Affect's of Temperature on Electric cables


Temperature is also affected on the cable. To choose a cable, the temperature is a most important factor. We know that summer season the temperature is reduced, but in hotter conditions, the current carrying capacity of cables is decreased, when a current passing through the cable, heat is produced due to internal resistance of the conductor.
The maximum conductor  temperature of a P.V.C insulated cable is 70 degree centi  for continuous operations and 130 degree centi for short periods of time (4 hours).
This means that the maximum ambient temperature in which a P.V.C insulated cable cam be operated economically is about 65 degree centi.

2 comments
Posted at 11:35 PM |  by Unknown
The voltage drop in a whole circuit always remains in permissible limit. I.E.E regulation states that the drop in voltage from the consumer's terminals to any point in the installation shall not exceed 2.5 percent of the declared supply voltage. When we use low resistance conductors cable, this problem is not produced. Since every cable has a definite resistance, then there is always a volt drop along a cable is occurred.'
For short run of cables, the value of volt drop is minimum, therefore it is neglected, but with long routes of cable the volt drop can become an important factor.
For example:
                           Declared supply voltages = 230 V
    Maximum permissible volt drop = 230/100 x(*) 2.5
                                                                           = 5.75 V
For a 250 V
Maximum permissible volt drop = 250/100 x(*) 2.5 =6 V

 As there is also a volt drop occurred in wiring from D.F.B to various sub-circuits points, the value of the volt drop should be about half of the above value i.e 3 volts.

Voltage drop in electric cables

The voltage drop in a whole circuit always remains in permissible limit. I.E.E regulation states that the drop in voltage from the consumer's terminals to any point in the installation shall not exceed 2.5 percent of the declared supply voltage. When we use low resistance conductors cable, this problem is not produced. Since every cable has a definite resistance, then there is always a volt drop along a cable is occurred.'
For short run of cables, the value of volt drop is minimum, therefore it is neglected, but with long routes of cable the volt drop can become an important factor.
For example:
                           Declared supply voltages = 230 V
    Maximum permissible volt drop = 230/100 x(*) 2.5
                                                                           = 5.75 V
For a 250 V
Maximum permissible volt drop = 250/100 x(*) 2.5 =6 V

 As there is also a volt drop occurred in wiring from D.F.B to various sub-circuits points, the value of the volt drop should be about half of the above value i.e 3 volts.

No comments
Posted at 11:31 PM |  by Unknown
The values of load current also depend upon the size of cable. Therefore when you installed a wiring always calculate the total load of wiring system. For places, where electrical installation is done; first of all, we know that the all power  in watts. Then we determine the current and adding 20% for future extension.

6 Lamps each 100 watt = 600 watt
4 Tubes each 40 watt = 160 watt
3 Fans each 80 watt = 240 watt
3 Socket outlets each 100 watt = 300 watt
Total load = 1300 watt

 Declared supply voltage = 240 v

 We know that:
                                                I = p/I = 1300/240 = 5.41 A
Adding 20% for future = 20/100 x(*) 5.41 = 1.08 A
Total load current = 5.41 + 1.08 = 6.49 A
It means that for 1300 watts load, the cable which is used. whose current rating is 6.49 A is 1/0.044 cable is 11 A.

Load Current of electric cable

The values of load current also depend upon the size of cable. Therefore when you installed a wiring always calculate the total load of wiring system. For places, where electrical installation is done; first of all, we know that the all power  in watts. Then we determine the current and adding 20% for future extension.

6 Lamps each 100 watt = 600 watt
4 Tubes each 40 watt = 160 watt
3 Fans each 80 watt = 240 watt
3 Socket outlets each 100 watt = 300 watt
Total load = 1300 watt

 Declared supply voltage = 240 v

 We know that:
                                                I = p/I = 1300/240 = 5.41 A
Adding 20% for future = 20/100 x(*) 5.41 = 1.08 A
Total load current = 5.41 + 1.08 = 6.49 A
It means that for 1300 watts load, the cable which is used. whose current rating is 6.49 A is 1/0.044 cable is 11 A.

No comments
Posted at 11:29 PM |  by Unknown
The choice of insulation on the cable depends on its environmental performance such as, ambient temperature.
Flexibility , water, oil and other chemicals and compatibility with other materials.
The function of insulation on the conductor is to protect the cable from leakage current and form electric shock. We use P.V.C, V.I.R vamished cambric or any of the several other types of insulation on the cables. The current carrying capacity of a cable also depends upon the types of insulation.
Insulation of Electric cable

Insulation of Electric cable

The choice of insulation on the cable depends on its environmental performance such as, ambient temperature.
Flexibility , water, oil and other chemicals and compatibility with other materials.
The function of insulation on the conductor is to protect the cable from leakage current and form electric shock. We use P.V.C, V.I.R vamished cambric or any of the several other types of insulation on the cables. The current carrying capacity of a cable also depends upon the types of insulation.
Insulation of Electric cable

1 comment
Posted at 11:28 PM |  by Unknown
Copper is a material used as a conductor in cables. Copper has low resistivity and higher conductivity. Copper is mostly used in cables but always used in annealed condition. Aluminium is  a good conductor. But copper conductor is preferred on aluminium conductor due to some reasons. Every person known that all the metals have different current carrying capacity.
The conductor of a cable may consist of solid metal or of wires or segments stranded together. In below table diagram the resistivity of some conductor material is shown.
table

Conductor material of cables with Resistivity and Temperature co-efficient table

Copper is a material used as a conductor in cables. Copper has low resistivity and higher conductivity. Copper is mostly used in cables but always used in annealed condition. Aluminium is  a good conductor. But copper conductor is preferred on aluminium conductor due to some reasons. Every person known that all the metals have different current carrying capacity.
The conductor of a cable may consist of solid metal or of wires or segments stranded together. In below table diagram the resistivity of some conductor material is shown.
table

No comments
Posted at 11:25 PM |  by Unknown
The essential components of a cable are a metallic conductor of low resistivity to carry the current and insulation around cable which provide dielectric medium for isolating conductors from one another and from their surroundings.
It is recommended that always choose the correct size of cable that is big enough to avoid wasted power in the form of excessive voltage drop. This wasted power is used in heating the cable, causing the temperature may be rise sufficiently to damage or even destroy the insulation of the cable and also efficiency of electrical devices is decreased. Cheaper cables are not good for electric wiring, because the power loss and voltage drop in these cables are very high.
Electric cables

 The chose the correct size of cable for electric  wiring, some important points to be remember.

 (1) Conductor material.
(2) Insulation.
(3) Type of wiring.
(4) Bunching.
(5) Load current.
(6) Voltage drops.
(7) Ambient temperature.
(8) Mechanical injury.
(9) Condition of installation at site.
(10) Short circuit capacity of a cable.

Choice of Electric cable

The essential components of a cable are a metallic conductor of low resistivity to carry the current and insulation around cable which provide dielectric medium for isolating conductors from one another and from their surroundings.
It is recommended that always choose the correct size of cable that is big enough to avoid wasted power in the form of excessive voltage drop. This wasted power is used in heating the cable, causing the temperature may be rise sufficiently to damage or even destroy the insulation of the cable and also efficiency of electrical devices is decreased. Cheaper cables are not good for electric wiring, because the power loss and voltage drop in these cables are very high.
Electric cables

 The chose the correct size of cable for electric  wiring, some important points to be remember.

 (1) Conductor material.
(2) Insulation.
(3) Type of wiring.
(4) Bunching.
(5) Load current.
(6) Voltage drops.
(7) Ambient temperature.
(8) Mechanical injury.
(9) Condition of installation at site.
(10) Short circuit capacity of a cable.

No comments
Posted at 11:24 PM |  by Unknown
Tinning :
"Copper and rubber, when brought into connect, react upon one another chemically. It was formerly thought that this action was due entirely to the sulfur in the rubber compound combining with the copper. Pure rubber, however, also reacts with the copper.
Coating the copper with tin or an alloy of tin affords the necessary protection. Tinned copper wires have been used for wiring and flexible cables.
Solid conductors have round circullar or square shape. The term protection is used to cover protection against mechanical damage, chemical or fire etc.
A term tinning is used is cables and conductors. Tinning means copper has a deleterious effect on rubber therefore tinning is used in each wire of the conductor of V.R>I cable. When we use P.V.C insulation on copper conductor, the copper conductors need not be tinned because there is no chemical effect between the P.V.C and bare conductor.

What is Tinning?

Tinning :
"Copper and rubber, when brought into connect, react upon one another chemically. It was formerly thought that this action was due entirely to the sulfur in the rubber compound combining with the copper. Pure rubber, however, also reacts with the copper.
Coating the copper with tin or an alloy of tin affords the necessary protection. Tinned copper wires have been used for wiring and flexible cables.
Solid conductors have round circullar or square shape. The term protection is used to cover protection against mechanical damage, chemical or fire etc.
A term tinning is used is cables and conductors. Tinning means copper has a deleterious effect on rubber therefore tinning is used in each wire of the conductor of V.R>I cable. When we use P.V.C insulation on copper conductor, the copper conductors need not be tinned because there is no chemical effect between the P.V.C and bare conductor.

No comments
Posted at 11:22 PM |  by Unknown
Electric Cable :
                "It is defined that the insulated conductor which is used for the purpose of electricity is known as cable"
The cable is consists of basic three parts, such as, conductor, insulation and mechanical protection.
A cable is either a stranded conductor or combination of conductors insulated from one another.
According to shape there are tow types of cables, one is circular cross-section and other is sector shaped.
Electric cables

 Conductor:
                        We know that "conductor are those materials in which electric current passes through easily"
A conductor is a wire or combination of wires not insulated from one another, suitable for carrying an electric current. All metals are conductor.
A stranded conductor is a conductor composed of a group of wires. The wires in a stranded wire or a cord. Cables may be insulated or bare and insulated cables may be sheathed with lead or armoured with wires or bands.
Copper is the most commonly used conductor material in cables, because it is cheap compare to other conductor materials.
Copper has high resistance against collision and it is "jointed easily. I shows the resistivity of some materials.

          Matel                                           Resisitivity
         
          Silver                   =                    1.4 x(*) 10-6
         Copper                 =                    1.5 x(*) 10-6
         Gold                      =                      2.36
        Aluminium         =                      2.6
        Tungsten             =                      5.6

 Solid and stranded conductors are used in cables. For ensure flexibility and ease of handing, conductors are stranded. A number of small wires twisted together which is equivalent to a single wire of the required size. The sizes of conductors range from lmm2 to 630mm2 . For e.g. (7/0.029) cable has a stranded conductors and every conductor size is (0.029). In flexible cable stranded are very thin, therefore elascity is very high. Stranded conductors are twisted in each other as a result, the resistance is decreased and make a fat conductor shape.
The stranded formations of stranded conductors comprised 1,3,5,7,9,37,61,127 wires etc. The reason for these odd number is that, when stranded, they form as near as possible a circular sectional shape.

Electric cable & conductor

Electric Cable :
                "It is defined that the insulated conductor which is used for the purpose of electricity is known as cable"
The cable is consists of basic three parts, such as, conductor, insulation and mechanical protection.
A cable is either a stranded conductor or combination of conductors insulated from one another.
According to shape there are tow types of cables, one is circular cross-section and other is sector shaped.
Electric cables

 Conductor:
                        We know that "conductor are those materials in which electric current passes through easily"
A conductor is a wire or combination of wires not insulated from one another, suitable for carrying an electric current. All metals are conductor.
A stranded conductor is a conductor composed of a group of wires. The wires in a stranded wire or a cord. Cables may be insulated or bare and insulated cables may be sheathed with lead or armoured with wires or bands.
Copper is the most commonly used conductor material in cables, because it is cheap compare to other conductor materials.
Copper has high resistance against collision and it is "jointed easily. I shows the resistivity of some materials.

          Matel                                           Resisitivity
         
          Silver                   =                    1.4 x(*) 10-6
         Copper                 =                    1.5 x(*) 10-6
         Gold                      =                      2.36
        Aluminium         =                      2.6
        Tungsten             =                      5.6

 Solid and stranded conductors are used in cables. For ensure flexibility and ease of handing, conductors are stranded. A number of small wires twisted together which is equivalent to a single wire of the required size. The sizes of conductors range from lmm2 to 630mm2 . For e.g. (7/0.029) cable has a stranded conductors and every conductor size is (0.029). In flexible cable stranded are very thin, therefore elascity is very high. Stranded conductors are twisted in each other as a result, the resistance is decreased and make a fat conductor shape.
The stranded formations of stranded conductors comprised 1,3,5,7,9,37,61,127 wires etc. The reason for these odd number is that, when stranded, they form as near as possible a circular sectional shape.

3 comments
Posted at 11:21 PM |  by Unknown
Subscribe to: Posts (Atom)
Blogger template. Proudly Powered by Blogger.
back to top