A generating station generates 3 phase power. In case of star, there is more line voltage (3^(0.5) times phase voltage) compared to delta with line voltage equal to phase voltage. More voltage means lower current for same power. Lower current means lower heat losses (I^2*R losses) in armature of alternator and also in transmission. Hence star is preferred over delta for generators. In case of motors, more phase voltage means more torque. So 3 phase motors are generally connected in delta as there is more phase voltage.
For same line voltage, a star connected alternator requires less insulation than delta connected alternator.
In star connection phase voltage=(line voltage)/root(3). Since induced emf per phase is directly proportional to number of turns, star connected alternator will require less number of turns for the same line voltage
In star connection the distorting line to neutral harmonics Do not appear as they effectively cancel out each other. Therefore line voltage remain sinusoidal.
There are two types of system available in electric circuit, single phase and three phase system. In single phase circuit, there will be only one phase, i.e the current will flow through only one wire and there will be one return path called neutral line to complete the circuit. So in single phase minimum amount of power can be transported. Here the generating station and load station will also be single phase. This is an old system using from previous http://time.In1882, new invention has been done on polyphase system, that more than one phase can be used for generating, transmitting and for load system. Three phase circuit is the polyphase system where three phases are send together from the generator to the load. Each phase are having a phase difference of 120°, i.e 120° angle electrically. So from the total of 360°, three phases are equally divided into 120° each. The power in three phase system is continuous as all the three phases are involved in generating the total power. The sinusoidal waves for 3 phase system is shown below-
The three phases can be used as single phase each. So if the load is single phase, then one phase can be taken from the three phase circuit and the neutral can be used as ground to complete the circuit.
Why Three Phase is preferred Over Single Phase?
There are various reasons for this question because there are numbers of advantages over single phase circuit. The three phase system can be used as three single phase line so it can act as three single phase system. The three phase generation and single phase generation is same in the generator except the arrangement of coil in the generator to get 120° phase difference. The conductor needed in three phase circuit is 75% that of conductor needed in single phase circuit. And also the instantaneous power in single phase system falls down to zero as in single phase we can see from the sinusoidal curve but in three phase system the net power from all the phases gives a continuous power to the load.
Till now we can say that there are three voltage source connected together to form a three phase circuit and actually it is inside the generator. The generator is having three voltage sources which are acting together in 120° phase difference. If we can arrange three single phase circuit with 120° phase difference, then it will become a three phase circuit. So 120° phase difference is must otherwise the circuit will not work, the three phase load will not be able to get active and it may also cause damage to the system. The size or metal quantity of three phase devices is not having much difference. Now if we consider the transformer, it will be almost same size for both single phase and three phase because transformer will make only the linkage of flux. So the three phase system will have higher efficiency compared to single phase because for the same or little difference in mass of transformer, three phase line will be out whereas in single phase it will be only one. And losses will be minimum in three phase circuit. So overall in conclusion the three phase system will have better and higher efficiency compared to the single phase system. In three phase circuit, connections can be given in two types:
Star connection
Delta connection
Star Connection
In star connection, there is four wire, three wires are phase wire and fourth is neutral which is taken from the star point. Star connection is preferred for long distance power transmission because it is having the neutral point. In this we need to come to the concept of balanced and unbalanced current in power system.
When equal current will flow through all the three phases, then it is called as balanced current. And when the current will not be equal in any of the phase, then it is unbalanced current. In this case, during balanced condition there will be no current flowing through the neutral line and hence there is no use of the neutral terminal. But when there will be unbalanced current flowing in the three phase circuit, neutral is having a vital role. It will take the unbalanced current through to the ground and protect the transformer. Unbalanced current affects transformer and it may also cause damage to the transformer and for this star connection is preferred for long distance transmission. The star connection is shown below-
In star connection, the line voltage is √3 times of phase voltage. Line voltage is the voltage between two phases in three phase circuit and phase voltage is the voltage between one phase to the neutral line. And the current is same for both line and phase. It is shown as expression below
Delta Connection
In delta connection, there is three wires alone and no neutral terminal is taken. Normally delta connection is preferred for short distance due to the problem of unbalanced current in the circuit. The figure is shown below for delta connection. In the load station, ground can be used as neutral path if required.
In delta connection, the line voltage is same with that of phase voltage. And the line current is √3 times of phase current. It is shown as expression below,
In three phase circuit, star and delta connection can be arranged in four different ways-
Star-Star connection
Star-Delta connection
Delta-Star connection
Delta-Delta connection
But the power is independent of the circuit arrangement of the three phase system. The net power in the circuit will be same in both star and delta connection. The power in three phase circuit can be calculated from the equation below,
Since, there is three phases, so the multiple of 3 is made in the normal power equation and the PF is power factor. Power factor is a very important factor in three phase system and some times due to certain error, it is corrected by using capacitors https://www.electrical4u.com/three-phase-circuit-star-and-delta-system/
CT (Current Transformer) Meters are installed on any connections with a load greater than 100 Amps. Conventional meters cannot be used to measure current for these larger connections as they would simply have to be too large to be practicable. A CT meter only measures a fraction of the current passing through the connection and a multiplier is applied to this reading to reflect the actual current.
There are two types of electric meters: self-contained (direct drive) and transformer rated.
Most meters used on homes or farms are self-contained. All electric energy used passes through the meter. These meters are designed to be used on services under 200 amperes. Current transformers are contained internally.
When services are more than 200 amperes, transformer-rated meters are used. As the name implies, these types of meters use current transformers (CTs) to measure the current flow, or total power being consumed. The information is recorded by the meter.
In donut-type CTs, there are two conductors, or windings. The primary winding is the line conductor that passes through the center of the CT. The secondary winding is the multiple turns of magnet wire around the core.
The CT transforms the primary current of the line conductor to a smaller, more easily managed current that is carried to the meter which is directly proportional to the primary current. This current is inversely proportional to the number of secondary turns of wire around the iron core.
For a 200:5A CT, the turns ratio is 40:1, giving the secondary current 1/40th of the primary current. For a 400:5A CT, the turns ratio is 80:1, giving a secondary current of 1/80th of the primary current.
The Burden rating (B) is the impedance of the circuit connected to the secondary winding. This impedance is the total opposing effect to the flow of current in an AC circuit. The Burden rating is the maximum amount of impedance before exceeding the minimum accuracy limits.
The current ratio difference between the actual current (primary) and the metered current (secondary) results in what is normally referred to as the multiplier. The correction factor is the factor by which the reading of a watthour meter must be multiplied to correct for the effects of the error ratio and phase angle of the CT.
AUTOCAD FREE TRIAL VERSIONS & AUTOCAD LTFull Version
First of all, any interested user can get a one-month Autodesk free trial version from Autodesk’s website.
Click DOWNLOAD AUTOCAD FOR FREE.
Select your operating system. Then, click NEXT.
Read the system requirements notice. Click NEXT.
Choose “Individual or Business User” from the list. Choose your language. And click NEXT.
Enter your personal information to create an Autodesk account. Alternatively, sign in to your existing Autodesk account.
Enter your business information. And click NEXT.
Read the Trial Notice and click BEGIN DOWNLOAD.
Install, and start using the free trial.
AUTOCAD FREE TRIAL VERSIONS & AUTOCAD LTEducational Version
Second, Autodesk offers a free educational version that runs on up to two personal devices for 3 years. It is meant for students and educational purposes.
Go to the Autodesk Education Community.
Choose AutoCAD.
Create an Autodesk account. Alternatively, sign in to your existing Autodesk account.
Then, click DOWNLOAD NOW.
Select the desired version, your operating system, and your preferred language.
The displayed serial number and product key are sent to your email address. And click BROWSER DOWNLOAD.
Next, install the free version.
When installing the CAD software, enter the serial number, and product key to unlock it.
When you start the program the first time, activate the license.
But what if you’re in a pickle: You liked the AutoCAD free trial and find out that you need AutoCAD, but there is no way you can afford it?
In this case, Autodesk offers a slimmed down version, AutoCAD LT, that “only” costs $380 per year. Of course, you can’t expect the same feature set as in the regular AutoCAD version. The biggest difference is that the light version doesn’t support 3D modeling and visualization.
View this table to find out if it does the job for you.
AutoCAD 360 App
Are you a smartphone jockey? Then you should take a look at AutoCAD 360. It’s a free AutoCAD version. And for a smartphone app, it’s quite capable.
The free AutoCAD 360 app is definitely more than a viewer. You can open and view DWG files, make accurate measurements and view coordinates, zoom and pan around drawings, store them in the cloud and share designs with colleagues and collaborators.
If you are willing to pay $5 a month, you get the Pro version. It offers a greater level of functionality and lets you draw, edit, move and scale objects.
But both paid and free AutoCAD 360 version lack some of the features of AutoCAD.
AUTOCAD FREE TRIAL VERSIONS & AUTOCAD LT Available Features
Available since 1982, AutoCAD is the most mature and stable CAD software on the market. As can be expected from a cutting-edge CAD program, this CAD software brings supports parametric modeling. Simply put, this enables users to make substantial changes to their designs by applying rules, or constraints, that govern their structure. Whenever the numerical value of such a constraint is changed, the entire design is modified.
Most noteworthy, a new feature in the 2018 release is the ability to import low-quality PDFs into AutoCAD and convert them into CAD lines. Moreover, the free mobile app brings CAD productivity to mobile devices which eliminates the need to print out drawings when visiting clients. As most products by Autodesk, this CAD software is connected to Print Studio, allowing you ease of access to your 3D printer.
Please note that the feature set of Windows and Mac versions differ somewhat before acquiring the AutoCAD free trial or paid version. To learn more take a look at this table on Autodesk’s website.
Use three iterations of Newton’s Method to approximate a zero of f(x) = x2 − 2. Use x = 1 as the initial guess. We need to know f (x)=2x, and we now can use the formula (we are given that x0 = 1). Use Newton’s Method to estimate the point of intersection of y = e−x2 and y = x.
If you in a Engineering College than your college may be having a licenced CATIA software for students. So, better would be to first try because I think using pirated / cracked version is not good idea.
Another , option would be to go for the TRIAL version of the software that is available on the official website of CATIA.
Or else if you do not find anywhere and could not afford the licenced version of CATIA then…..
The best place that you can find on the internet to download much of resources either for entertainment or educational you can get most of it by just following some simple steps.
Any software that you need just type in google index of ‘name of software’
For example : if you want to download solidworks then just type on google : index of solidworks and hit ENTER.
The first 2–3 links that you get in the search results will give you the software you need. For CATIA : http://s2.bitdownload.ir/Enginee… For softwares :http://s2.bitdownload.ir/Enginee…
You can also download any movie , TV series and many thing by typing those two MAGICAL WORDS index of …..
hope it will help…
Edit 1:
Hey Guys ….
Catia V5 2018 Student Edition is available free for 1 year on the official Website CATIA V5 Student Edition
Just apply the promocode and have a great experience learning..
Varun
A generating station generates 3 phase power. In case of star, there is more line voltage (3^(0.5) times phase voltage) compared to delta with line voltage equal to phase voltage. More voltage means lower current for same power. Lower current means lower heat losses (I^2*R losses) in armature of alternator and also in transmission. Hence star is preferred over delta for generators. In case of motors, more phase voltage means more torque. So 3 phase motors are generally connected in delta as there is more phase voltage.
Varun
Varun
There are two types of system available in electric circuit, single phase and three phase system. In single phase circuit, there will be only one phase, i.e the current will flow through only one wire and there will be one return path called neutral line to complete the circuit. So in single phase minimum amount of power can be transported. Here the generating station and load station will also be single phase. This is an old system using from previous http://time.In1882, new invention has been done on polyphase system, that more than one phase can be used for generating, transmitting and for load system. Three phase circuit is the polyphase system where three phases are send together from the generator to the load. Each phase are having a phase difference of 120°, i.e 120° angle electrically. So from the total of 360°, three phases are equally divided into 120° each. The power in three phase system is continuous as all the three phases are involved in generating the total power. The sinusoidal waves for 3 phase system is shown below-
The three phases can be used as single phase each. So if the load is single phase, then one phase can be taken from the three phase circuit and the neutral can be used as ground to complete the circuit.
Why Three Phase is preferred Over Single Phase?
There are various reasons for this question because there are numbers of advantages over single phase circuit. The three phase system can be used as three single phase line so it can act as three single phase system. The three phase generation and single phase generation is same in the generator except the arrangement of coil in the generator to get 120° phase difference. The conductor needed in three phase circuit is 75% that of conductor needed in single phase circuit. And also the instantaneous power in single phase system falls down to zero as in single phase we can see from the sinusoidal curve but in three phase system the net power from all the phases gives a continuous power to the load.
Till now we can say that there are three voltage source connected together to form a three phase circuit and actually it is inside the generator. The generator is having three voltage sources which are acting together in 120° phase difference. If we can arrange three single phase circuit with 120° phase difference, then it will become a three phase circuit. So 120° phase difference is must otherwise the circuit will not work, the three phase load will not be able to get active and it may also cause damage to the system. The size or metal quantity of three phase devices is not having much difference. Now if we consider the transformer, it will be almost same size for both single phase and three phase because transformer will make only the linkage of flux. So the three phase system will have higher efficiency compared to single phase because for the same or little difference in mass of transformer, three phase line will be out whereas in single phase it will be only one. And losses will be minimum in three phase circuit. So overall in conclusion the three phase system will have better and higher efficiency compared to the single phase system. In three phase circuit, connections can be given in two types:
Star Connection
In star connection, there is four wire, three wires are phase wire and fourth is neutral which is taken from the star point. Star connection is preferred for long distance power transmission because it is having the neutral point. In this we need to come to the concept of balanced and unbalanced current in power system.
When equal current will flow through all the three phases, then it is called as balanced current. And when the current will not be equal in any of the phase, then it is unbalanced current. In this case, during balanced condition there will be no current flowing through the neutral line and hence there is no use of the neutral terminal. But when there will be unbalanced current flowing in the three phase circuit, neutral is having a vital role. It will take the unbalanced current through to the ground and protect the transformer. Unbalanced current affects transformer and it may also cause damage to the transformer and for this star connection is preferred for long distance transmission. The star connection is shown below-
In star connection, the line voltage is √3 times of phase voltage. Line voltage is the voltage between two phases in three phase circuit and phase voltage is the voltage between one phase to the neutral line. And the current is same for both line and phase. It is shown as expression below
Delta Connection
In delta connection, there is three wires alone and no neutral terminal is taken. Normally delta connection is preferred for short distance due to the problem of unbalanced current in the circuit. The figure is shown below for delta connection. In the load station, ground can be used as neutral path if required.
In delta connection, the line voltage is same with that of phase voltage. And the line current is √3 times of phase current. It is shown as expression below,
In three phase circuit, star and delta connection can be arranged in four different ways-
But the power is independent of the circuit arrangement of the three phase system. The net power in the circuit will be same in both star and delta connection. The power in three phase circuit can be calculated from the equation below,
Since, there is three phases, so the multiple of 3 is made in the normal power equation and the PF is power factor. Power factor is a very important factor in three phase system and some times due to certain error, it is corrected by using capacitors https://www.electrical4u.com/three-phase-circuit-star-and-delta-system/
Varun
Try this
https://youtu.be/1PT6hlGVBnI?t=2
Vignesh
You can download most of the engineering mechanics book from this link
https://easyengineering.net/engineeringmechanicsbooks/
Vignesh
What is a CT meter?
CT (Current Transformer) Meters are installed on any connections with a load greater than 100 Amps. Conventional meters cannot be used to measure current for these larger connections as they would simply have to be too large to be practicable. A CT meter only measures a fraction of the current passing through the connection and a multiplier is applied to this reading to reflect the actual current.
There are two types of electric meters: self-contained (direct drive) and transformer rated.
Most meters used on homes or farms are self-contained. All electric energy used passes through the meter. These meters are designed to be used on services under 200 amperes. Current transformers are contained internally.
When services are more than 200 amperes, transformer-rated meters are used. As the name implies, these types of meters use current transformers (CTs) to measure the current flow, or total power being consumed. The information is recorded by the meter.
In donut-type CTs, there are two conductors, or windings. The primary winding is the line conductor that passes through the center of the CT. The secondary winding is the multiple turns of magnet wire around the core.
The CT transforms the primary current of the line conductor to a smaller, more easily managed current that is carried to the meter which is directly proportional to the primary current. This current is inversely proportional to the number of secondary turns of wire around the iron core.
For a 200:5A CT, the turns ratio is 40:1, giving the secondary current 1/40th of the primary current. For a 400:5A CT, the turns ratio is 80:1, giving a secondary current of 1/80th of the primary current.
The Burden rating (B) is the impedance of the circuit connected to the secondary winding. This impedance is the total opposing effect to the flow of current in an AC circuit. The Burden rating is the maximum amount of impedance before exceeding the minimum accuracy limits.
The current ratio difference between the actual current (primary) and the metered current (secondary) results in what is normally referred to as the multiplier. The correction factor is the factor by which the reading of a watthour meter must be multiplied to correct for the effects of the error ratio and phase angle of the CT.
Vignesh
AUTOCAD FREE TRIAL VERSIONS & AUTOCAD LT
AUTOCAD FREE TRIAL VERSIONS & AUTOCAD LTFull Version
First of all, any interested user can get a one-month Autodesk free trial version from Autodesk’s website.
Click DOWNLOAD AUTOCAD FOR FREE.
Select your operating system. Then, click NEXT.
Read the system requirements notice. Click NEXT.
Choose “Individual or Business User” from the list. Choose your language. And click NEXT.
Enter your personal information to create an Autodesk account. Alternatively, sign in to your existing Autodesk account.
Enter your business information. And click NEXT.
Read the Trial Notice and click BEGIN DOWNLOAD.
Install, and start using the free trial.
AUTOCAD FREE TRIAL VERSIONS & AUTOCAD LTEducational Version
Second, Autodesk offers a free educational version that runs on up to two personal devices for 3 years. It is meant for students and educational purposes.
Go to the Autodesk Education Community.
Choose AutoCAD.
Create an Autodesk account. Alternatively, sign in to your existing Autodesk account.
Then, click DOWNLOAD NOW.
Select the desired version, your operating system, and your preferred language.
The displayed serial number and product key are sent to your email address. And click BROWSER DOWNLOAD.
Next, install the free version.
When installing the CAD software, enter the serial number, and product key to unlock it.
When you start the program the first time, activate the license.
AUTOCAD FREE TRIAL VERSIONS & AUTOCAD LTAutoCAD LT
AutoCAD-LT
But what if you’re in a pickle: You liked the AutoCAD free trial and find out that you need AutoCAD, but there is no way you can afford it?
In this case, Autodesk offers a slimmed down version, AutoCAD LT, that “only” costs $380 per year. Of course, you can’t expect the same feature set as in the regular AutoCAD version. The biggest difference is that the light version doesn’t support 3D modeling and visualization.
View this table to find out if it does the job for you.
AutoCAD 360 App
Are you a smartphone jockey? Then you should take a look at AutoCAD 360. It’s a free AutoCAD version. And for a smartphone app, it’s quite capable.
The free AutoCAD 360 app is definitely more than a viewer. You can open and view DWG files, make accurate measurements and view coordinates, zoom and pan around drawings, store them in the cloud and share designs with colleagues and collaborators.
If you are willing to pay $5 a month, you get the Pro version. It offers a greater level of functionality and lets you draw, edit, move and scale objects.
But both paid and free AutoCAD 360 version lack some of the features of AutoCAD.
AUTOCAD FREE TRIAL VERSIONS & AUTOCAD LT Available Features
Available since 1982, AutoCAD is the most mature and stable CAD software on the market. As can be expected from a cutting-edge CAD program, this CAD software brings supports parametric modeling. Simply put, this enables users to make substantial changes to their designs by applying rules, or constraints, that govern their structure. Whenever the numerical value of such a constraint is changed, the entire design is modified.
Most noteworthy, a new feature in the 2018 release is the ability to import low-quality PDFs into AutoCAD and convert them into CAD lines. Moreover, the free mobile app brings CAD productivity to mobile devices which eliminates the need to print out drawings when visiting clients. As most products by Autodesk, this CAD software is connected to Print Studio, allowing you ease of access to your 3D printer.
Please note that the feature set of Windows and Mac versions differ somewhat before acquiring the AutoCAD free trial or paid version. To learn more take a look at this table on Autodesk’s website.
Vignesh
Use three iterations of Newton’s Method to approximate a zero of f(x) = x2 − 2. Use x = 1 as the initial guess. We need to know f (x)=2x, and we now can use the formula (we are given that x0 = 1). Use Newton’s Method to estimate the point of intersection of y = e−x2 and y = x.
Vignesh
If you in a Engineering College than your college may be having a licenced CATIA software for students. So, better would be to first try because I think using pirated / cracked version is not good idea.
Another , option would be to go for the TRIAL version of the software that is available on the official website of CATIA.
Or else if you do not find anywhere and could not afford the licenced version of CATIA then…..
The best place that you can find on the internet to download much of resources either for entertainment or educational you can get most of it by just following some simple steps.
Any software that you need just type in google index of ‘name of software’
For example : if you want to download solidworks then just type on google : index of solidworks and hit ENTER.
The first 2–3 links that you get in the search results will give you the software you need.
For CATIA : http://s2.bitdownload.ir/Enginee…
For softwares : http://s2.bitdownload.ir/Enginee…
You can also download any movie , TV series and many thing by typing those two MAGICAL WORDS index of …..
hope it will help…
Edit 1:
Hey Guys ….
Catia V5 2018 Student Edition is available free for 1 year on the official Website
CATIA V5 Student Edition
Just apply the promocode and have a great experience learning..
Vignesh
Hi, you may download it from here..
https://mega.nz/#!Fos3hC5Q!Oq157aF4YPHsArwh1S2h4J85PiON_kN3j3lpdrZLoAI
Installation is easy. Please personal message me if you face any difficulty.
Please upvote if you like it.