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To convert angles from degrees to radians, use the numpy.radians() method in Python Numpy. The method returns the corresponding radian values. This is a scalar if x is a scalar. The 1st parameter is an input array in degrees. The 2nd and 3rd parameters are optional.The 2nd parameter is an ndarray, A location into which the result is stored. If provided, it must have a shape that the inputs broadcast to. If not provided or None, a freshly-allocated array is returned. A tuple (possible only as a keyword argument) must have length equal to the number of outputs.The 3rd parameter ... Read More
The natural logarithm log is the inverse of the exponential function, so that log(exp(x)) = x. The natural logarithm is logarithm in base e. The method returns the natural logarithm of x, elementwise. This is a scalar if x is a scalar. The 1st parameter is the input value, array-like. The 2nd parameter is out, a location into which the result is stored. If provided, it must have a shape that the inputs broadcast to. If not provided or None, a freshly-allocated array is returned. A tuple (possible only as a keyword argument) must have length equal to the number ... Read More
String EfficiencyThe suspension insulator is the one which consists of a number of porcelain discs connected in series by metal links in the form of a string.The voltage applied across the string of the suspension insulators is not uniformly distributed across the various discs, i.e. the disc nearest to the line conductor has much higher potential than the other discs. This unequal potential distribution is undesirable and it is usually expressed in terms of string efficiency. Therefore, the string efficiency of the suspension type insulator is defined as follows −“The ratio of voltage across the whole string to the product ... Read More
To merge dataframes of different length, we need to use the merge() method. Let’s say the following is our 1st DataFrame with length 4 −dataFrame1 = pd.DataFrame( { "Car": ['BMW', 'Lexus', 'Audi', 'Jaguar'] } ) print("DataFrame1 ...", dataFrame1) print("DataFrame1 length = ", len(dataFrame1))Following is our 2nd DataFrame with length 6 −dataFrame2 = pd.DataFrame( { "Car": ['BMW', 'Lexus', 'Audi', 'Mercedes', 'Jaguar', 'Bentley'] } ) print("DataFrame2 ...", dataFrame2) print("DataFrame2 length = ", len(dataFrame2))Now, merge DataFrames using the merge() −mergedRes = dataFrame2.merge(dataFrame1, how='left')ExampleFollowing is the code −import pandas as pd # ... Read More
The choice of operating frequency for electric heating is a significant factor for heating because it greatly affects the work to be heated and the method of its heating, whether dielectric heating or induction heating.In practice, the furnaces operating on power frequency of 50 Hz can be of 1 MW capacity, those operating on medium frequencies (about 500 Hz to 1000 Hz) have a capacity of 50 kW and those operating on high frequencies (about 1 MHz to 5 MHz) have capacities ranging from 200 kW to 500 kW.Therefore, the factors which are considered while selecting the frequency for electric ... Read More
Transmission Line SupportsThe supporting structures used for overhead transmission line conductors, such as poles and towers, are called the transmission line supports.Generally, the transmission line supports supposed to possess the following properties −The line supports should have high mechanical strength so that it can withstand the weight of conductors and wind loads, etc.It should be light in weight without the loss of its mechanical strength.It should have longer life.It should be cheap in cost and economical to maintain.Accessibility of line conductors for maintenance is to be easy.There are various types of line supports available. The choice of supporting structure for ... Read More
What is Electric Supply System?The carrier of electrical power from power generating station to the consumer’s premises for its utilisation is called the electrical supply system.The whole electric supply system is segmented into three principle components, viz. −Power generating stationTransmission systemDistribution systemThe electric power is produced at the power generating station which are located quite away from the consumers. Then, the power is transmitted over large distances to load centres with the help of conductors called transmission lines. Finally, it is distributed to a large number of consumers through a distribution system.Types of Electric Supply SystemDepending upon the types of ... Read More
The element of the transmission line by which the line conductors are insulated from supports is known as line insulator. The insulators used in the transmission lines are of various types. Some of the important types of insulators are given as follows −Pin Type InsulatorSuspension Type InsulatorStain InsulatorShackle InsulatorPin Type InsulatorsThe pin type insulator is shown in the figure. The pin type insulator is fitted to the cross-arm on the pole. The pin type insulator has a groove on the upper end of the insulator for housing the line conductor. The line conductor passes through this groove and is bounded ... Read More
Corona Effect in Overhead Transmission LineThe phenomenon of violet glow, hissing sound and production of ozone gas in an overhead transmission line is known as corona.When a very high voltage is applied across two conductors of the overhead transmission line whose spacing is large as compared to their diameters. When this applied voltage exceeds a certain value (called critical disruptive voltage), then the conductors are surrounded by a faint violet glow that is known as corona effect.In practice, the corona effect is accompanied by a hissing sound, production of ozone, power loss and radio interference. The higher is the transmission ... Read More
What are Insulators?Insulators are the elements of transmission system which provide necessary insulation between line conductors and supports and hence, prevent any leakage current from the conductors to the earth.The line conductors in the overhead transmission lines should be supported on the poles or towers in such a way that the current from the conductors do not flow to the earth through the supports which means the line conductors must be properly insulated from the supports. This is achieved by using the insulators between the line support and conductors.The commonly used material for manufacturing the insulators of overhead transmission line ... Read More