Brake test on dc compound motor theory pdf

Aug 08, 2017 this video provides all the basic concept of electric braking and application of dc motor in detail i created this video with the youtube video editor. In this method, a brake is applied to a watercooled pulley mounted on the motor shaft as shown in fig. In electrical terms, parallel is generally denoted as shunt. Dc motors although ac motors are used in most of the cases, dc motors have many applications and used for multipurpose applications.

Overview the acdc motor theory course was specifically developed for electricians and electronic technicians as well as for the multicraft training needs of process and manufacturing facilities. Brushed dc motor theory and operation chris joyce, shane skikne, evan simpson, james nee january 8, 2014 abstract this study looked into the e ect of changing the material within the rotor of an electric motor. Series wound dc motor as we said before that this type of dc motor is a selfexcited dc motor which converts electrical power into mechanical power based on electromechanical law, but in this motor, the field winding is connected in series to the armature winding. Objective identify the components of an ac motor and explain their function. Dec 01, 2016 dc machines can be tested by three different methods namely direct method, indirect method and regenerative method. Working principle from the above circuit diagram, we can conclude that if we want to increase the speed of the shunt motor, we will vary the field resistance. Prior to teslas inventions, direct current motors were the presiding type of motor. One end of the rope is fixed to the floor via a spring balance s and a known mass is suspended at the other end. Brake test on dc shunt motor free download as word doc. The electric braking of a dc motor is of three types, i rheostatic or dynamic braking, ii plugging or reverse current braking and iii regenerative beaking.

What is a dc shunt motor and its advantage and disadvantage. To find out how to reverse the direction of rotation of a series dc motor. Brake test of dc motor is carried out as shown in figure below. Speed control of dc shunt motor with field and armature. Swinburnes test and speed control of dc shunt motor. The power required to test a large machine is small. One end of the band is fixed to earth via a spring balance s. One of these two machines is operated as a generator to supply the mechanical power to the motor. It is a full load test and it requires two identical machines which are coupled to each other. To perform the brake test on the given dc compound motor and to. The brake band is fixed with the help of wooden blocks gripping the pulley.

Because the magnetic field rotates in this way, an ac motor does not need power or mechanical aid to be applied to the rotor. Brake test is used to determine the efficiency of comparatively. A dc series motor is one type of dc motor in which field winding is connected in series with the armature winding. The armature and its windings are located in the path of this magnetic field, and. Download as docx, pdf, txt or read online from scribd.

Introduction a series dc motor is a motor whose filed windings consists of a relatively few turns connected in series with the armature circuit. Make the connections as per the circuit give supply to the motor, by closing dpst switch start the motor with the help of 3 point starter. Experiment 7 series dc motor i objectives to determine the torquespeed characteristic curve. Advantages and disadvantages of dc shunt motor load answers. The brake test is the one kind of load test on dc shunt motor. As the constant loss is known the efficiency can be predetermined at any load. Dc motors designed for your application dc motor applications tecowestinghouse motor company dc motors are ideally suited to a multitude of industrial. Electrical machinel dc laboratory manual grietelectrical and. Aug 03, 2018 hopkinsons test is another useful method of testing the efficiency of a dc machine. That is the reason behind naming it a dc shunt motor. The main advantages of the swinburnes test are as follows. Construction and principle of operation of the shunt dc motor. Direct method of testing of dc machine, also known as brake test if carried out for a dc motor will be discussed in this post. This particular motor is of the permanent magnet type, with wire windings only on the armature.

Brake test on dc compound motor free download as word doc. Characteristics of dc compound motor in dc compound motors both shunt field and series field will be acting simultaneously. The tension of rope can be adjusted with the help of swivels obviously. Dc motor principle a machine that converts dc power into mechanical energy is known as dc motor.

Dc injection brakes only require a small module located with the other motor switchgear andor drivers, mounted in a remote and convenient location, whereas a friction brake must be mounted somewhere on the rotating system. The dc shuntwound motor, running on direct current, has its field windings placed in parallel to the armature. Because in the case of large motor it is different to dissipate the large amount of heat generated at the brake. Volume 2 of 4 module 3 dc circuits this module introduces the rules associated with the reactive components of inductance and capacitance and how they affect dc circuits. Aug 22, 2018 types of braking in a dc motor august 22, 2018 february 24, 2012 by electrical4u hello electrical people, you already know about the different types of motors that are available today and in this article, i shall discuss about the various techniques used to stop a dc motor or to bring it to rest as we cut off the supply. A direct current moto r, dc is named according to the connection of the field winding with the armature. Advantages and disadvantages of dc shunt motor load. It is a direct method and consists of applying a brake to a. Load test on singlephase transformer and three phase. Using belt tightening hand wheels h1 and h2, the load of motor is adjusted to its rated value. Jun 02, 2015 brake test it is a direct method and consists of applying a brake to a watercooled pulley mounted on the motor shaft as shown in fig. C motor field windings 25092011 by lemau 2 comments d.

Load characteristics of dc compound generator with differential and cumulativeconnections. Riosque y zack special edition hd recommended for you. Same voltage is applied to both shunt winding and armature in this motor. A compound wound motor has both a series and a shunt field winding, i. What is theory of brake test on dc shunt motor answers.

Dc injection braking is a method of braking in which direct current dc is applied to the stationary windings of an ac motor after the ac voltage is removed. Atomic structure, energy band diagram, compare silicon and germanium, hole current, intrinsic semiconductor extrinsic semiconductor, compare voltage amplifier power amplifier, compare audio amplifier tuned amplifier, compare transistor scr, compare transistor mosfet, compare holding current latching current. Brake test on dc shunt motor electric motor electrical engineering. Our test facility is one of the most advanced in the world. The selfexcited motors are further classified as shunt wound or shunt motor, series wound or series motor and compound wound or. Series wound dc motor construction, principle, speed and torque. An ac motor works by applying alternating current to stator windings, which produce a rotating magnetic field. Open circuit and load characteristics of separately and self excited dc shunt generators. This course consists of 11 interactive, online lessons that address ac and dc motor theory. Two basic methods used for braking a motor dc injection. A dc injection brake system can be used as an alternative to a friction brake system. The dc motor contains a stator and a rotor, the latter being more commonly called an armature. The performance of any motor can be judged from its characteristic curves known as motor characteristics.

Brake test is also a method of finding efficiency of dc motors. Brake test on dc shunt motor electric motor electrical. Brake test also called as direct loading test of testing the motor. Scribd is the worlds largest social reading and publishing site. A dc motor may be thought of as a series of electromagnets, radially spaced around a common shaft. In such motors when armature current increases the field flux increases. The result is a high standard of quality control that reinforces our manufacturing excellence. Module 2 basic dc theory this module describes the basic concepts of direct current dc electrical circuits and discusses the associated terminology. Load characteristics of dc compound generator with differential and cumulative connection. Dc motors applied for the momentarily deliver rated around three or more times from their torque. In cumulative compound motors the series field assists the shunt field. Generally, this test can be done for the low rated dc machines. As such, the field windings and armature are connected in a parallel combination, and in electrical terminology a parallel combination is known as a shunt.

Another simpled method of measuring motor output is by the use of poney brake one form of the diagram. This is an efficient and effective method of braking most ac motors. Dec 21, 2017 81 videos play all dc machines complete course includes fundamentals, motors and generators electrical is easy mix play all mix electrical is easy youtube troubleshooting a motor starter. A belt around the air cooled pulley has its end attached to the spring balance s1 and s2. Several paragraphs that explain the motivation of the. Two basic methods used for braking a motor dc injection and dynamic photo credit. The open circuit characteristics for a dc generator are determined as follows. To conduct the no load test on the dc shunt motor and determine its. Connect the brake supply cable inserted into the motor terminal box according to the diagram on the inside of the box cover, while connecting the brake with the motor maintain all the necessary. First, one is separately excited dc motor and selfexcited dc motor. Load characteristics of dc shunt and compound motor.

To obtain the performance characteristics of a dc shunt motor by load test. Characteristics of dc series motor studyelectrical. The field current lf is obtained from an external independent dc source. In case of dc shunt motors, armature is disconnected from the supply and a rheostat variable resistor is connected across it. Speed control of dc shunt motor with field and armature rheostat control 79 2. Thus, this method is an economical and convenient method of testing of dc machines. In a brushed dc motor, the coils on the rotor utilize the motors magnetic eld to create torque on the axle.

The stator contains one or more windings per pole, all of which are designed to carry direct current, th ereby setting up a magnetic field. C motor is the one of common application for industrial. In this article we are going to discuss about brake test on d. The final stage of brake installation onto the motor is mounting the fan and inserting the brake supply cable into the motor terminal box, 8. In this post, we will look into the characteristics of a dc series motor. As resistance increased, the value of the field current will reduce. Brake test on dc compound motor electric motor electrical. Write the necessary magnetic polarities n for north and s for south on the armatures electromagnet pole tips, in order to. To conduct load test on dc compound motor and to find its efficiency. This parallel configuration allows independent path of current for field winding and armature.