Input Voltage: For a fixed load, the speed of the motor is affected by the applied voltage. There are three different types of DC motors; namely, permanent magnet DC motor (PMDC Motor), separately excited DC motor, and self-excited DC motor. By using a laboratory test desk built specially to test DC Series Motor and 3-phase IM, several practical tests could be performed. However, in a separately excited DC motor, a separate supply is used to excitation both the armature coil and the field coil. 1. 6) Then the calculation had be made and the result also recorded in Table 2.6. In this experiment, a load test on DC shunt motor will be conducted. This desk include the electric motor, an electronic controller and Battery Bank with a charger, enabling the practically verification of performance and behaviour of the complete electric drive system, which contains the exact parts that would be Shunt DC Motor The shunt motor is probably the most common dc motor used in industry today. A high speed or heavy duty motor can see problems where the rotor conductors are crimped into the comm segments. = (2*3.14*N* (W-S)*9.81*r)/60. On the other hand, a compound DC motor can be used even at no load. The purpose of this load test is to test which is used to test the performance. 2. Q2. 2. I = Current taken by the motor in amperes. Apparatus Range Type Quantity 1 Ammeter (0-20)A MC 1 2 Voltmeter (0-300)V MC 1 3 Tachometer (0-3000) rpm Digital 1 4 Connecting Wires 2.5sq.mm. The motor voltage can be changed by inserting a resistor in series with DC motor. CIRCUIT DIAGRAM Fig A shows the circuit diagram for speed control of DC motor. There are several tests that are conducted for testing a dc machine (generator or motor) to judge its performance. Connections are made as per the There are several tests that are conducted for testing a dc machine ( generator or motor) to judge its performance. The most important performance tests to be conducted on the dc machine are: The magnetization or open-circuit test. The load characteristic. The determination of the efficiency curve.
8. 4. 2. Copy. View LOAD TEST ON DC SHUNT MOTOR.pdf from EE 1 at RCM Polytechnic. In such case, due to the armature reaction E starts decreasing as shown by dotted line in the Fig. [PDF] CS8083 Multi-core Architectures and Programming MCQ Multi Choice Questions, Lecture IT8076 Software Testing Lecture Notes, Books, Important Part-A 2 Marks Questions
[4] 2.3 DC generator Experiment Set-up Analog ammeter and voltmeter are provided Continue reading "Panel For Load Test Of DC Answer (1 of 2): In Swinburne's test machine under test is run on no load at rated speed and rated voltage. It will run at some speed within the limits. Regenerative braking cannot be used for stopping the motor.
DC motor testing is done with the same instrument used for AC motor tests. The tests used are also the same. Since multiple coils and windings are tested, the procedures for doing the tests are different. Multi-coil tests are available. This semi-automatic process makes testing multiple coils and DC armatures fast and easy. The efficiency of the motor is determined by using the formula m = (w (S 1 S 2) 9.81) / V t I l * 100. where w is the weight of the machine, S1 and S2 denote the spring balance, Vt is the terminal voltage, I l is the line current. This current will flow through the series field and armature, the speed tends to increase so that back emf may approach the applied voltage in magnitude. Hence, it is difficult to perform Swinburne's test on large series motors. This type of motor has good speed regulation even as the load varies, but does not have the starting torque of a series DC Motor. The torque load was adjusted from 0Nm to 2Nm. Then careful to use a low voltage for B+ and B-. So don't connect it up like a series motor. Data collection includes 12 temperatures, power, HP, efficiency, power factor, torque, speed, currents, and voltages. PROCEDURE 1. Output power = (2*3.14*N*Tsh)/60. 2. Since it is a no-load test, a series motor at no-load attains dangerously high speed. Increase in load torque = decrease in speed. In a shunt motor, the shunt field current Ish is always a constant since the field winding is connected in parallel to the armature winding and the supply voltage. For example: let's assume we have a 5055-3000kV Brushless Outrunner Motor Motor KV: 2300 The phase-to-phase voltage for a 3-phase supply, or the phase-to-neutral voltage for a single phase supply Refer below image of a dc motor JPD001 Electric Water-jet Pump Drive Injector Engine Propulsion 1KG Thrust for RC Boat or Surfboard yes.it is possible to start dc series generator on no load condition. Q1. Testing of DC Series Motors. APPARATUS REQUIRED: S.No. Increase in voltage = increase in speed. In a shunt motor, the field and armature windings are connected in parallel. 2.2 DC Machine The stator of a dc machine has projected poles ( salient poles) and a coil is wound on these poles as shown in Fig.6 . a. Ia. A water-cooled pulley is attached to the shaft of the motor. These characteristics are determined by keeping the following two relations in mind. The figure that depicts the load test on the motor is shown in the figure below. BRAKE TEST ON DC SHUNT MOTOR Another method of testing the d.c. motor is brake test method. Therefore the no load current of DC Series Motor can be assumed approximately zero i.e. DC motors were widely used in whole over the world. 4. AIM: 1) To plot the open circuit characteristics (O.C.C) of a DC shunt generator and to determine its critical via a series resistance connected to the field winding externally. The basic behavior of a series dc motor is due to the fact that the flux is directly proportional to the armature current, at least until saturation is reached. ing. DC motors are used to turn direct current electrical energy to mechanical energy. All DC load banks are portable, heavy-duty, and equipped with safety features for overload and over-temperature protection. Calculate the percentage change in torque if the load is changed so that the motor takes of 30 A. b. Ia2. To find the various performance parameters such as torque, input power, output power. 2. To determine the efficiency of the given DC compound motor by conducting load test. 3. To obtain the electrical and mechanical characteristics for given DC compound motor. If a machine produces too much heat then it can affect the insulation of the machine and ultimately it can cause the breakdown of the machine. In this method, the motor is put on the direct load by means of a belt and pulley arrangement. [PDF] CS8083 Multi-core Architectures and Programming MCQ Multi Choice Questions, Lecture IT8076 Software Testing Lecture Notes, Books, Important Part-A 2 Marks Questions 2.1 DC Shunt Motor Experiment Set-up Figure 2: This is how the experiment was setup for DC shunt motor. A Shunt DC Motor connects the armature and field windings in parallel or shunt with the common D.C. power source. The temperature rise test. We can perform a motor load test up to 7000 horsepower AC or 4500 AMP, 750V for DC motors. 4.2.1 Adding a DC-load (LOAD) to the DC-motor (MOTOR) To determine the DC-motor steady state characteristics, a second DC-motor will be axially coupled to the motor under test (MUT). It is used for controlling the speed above the no-load speed of the motor driving. In this paper, through an experimental work armature resistive drive control technology and And all SepEx motors are not the same as far as field strength and resistance. As the load on the motor increases, its flux increases too. Download Series DC motors PDF.
The speed of a DC motor is directly proportional to the voltage across the armature terminals and inversely proportional to the flux () due to the field windings (N 1 / ), that is N 1 / I sh..
As seen earlier, an increase in the flux in the motor causes a decrease in its 9. SAFETY. Objective: (a) To perform the load test on dc shunt motor. On the coldest days of winter the series motor that starts your car overcomes the extreme cold temperatures and thick lubricant to get your car going. Brake adjusting the tension of belt, the load is adjusted to give the various values of currents. Which test is used to determine the efficiency of a traction motor? A DC series motor has all the 6 fundamental components-axle, rotor (armature), stator, commutator, field magnet(s) and brushes-that are present in a generic DC motor. Apparatus Range Type Quantity 1 Ammeter (0-10)A MC 1 2 Voltmeter (0-300)V MC 1 2.5sq.mm. Load Test on DC Series Motor Ex No: 1 DATE: 23.07.19 OBJECTIVE: To conduct the load test on the given DC series motor and Open circuit and short circuit tests on single phase transformer. These power resistors can be combined in series and/or parallel to create load resistances of 20 , 16 , 12 , 8 , 4 , 2 , and 1 The basic process for testing the motor is as follows: 1. 5. Load test on single-phase transformer and three phase transformers. To investigate the performance characteristics of dc shunt motor by applying eddycurrent load To determine the efficiency of DC shunt motor. For d.c. series motor, if Ia is the armature current then the torque developed is. If we assume that the machine is unsaturated, then phi f equal to some K f into I a for series machine. 3. You have a SepEx motor. Definition: A DC series motor is a machine that is used at a place where high torque operating conditions are required. Figure 9: Line Fed Motor Best Answer. SUPPORT. Magtrols dynamometers, electronics and software are used for testing all types of electric and pneumatic motors, gas engines and gearheads, as well as servo drives and inverters. To this model, appropriate blocks for controlling the active load (a DC-generator whose electromagnetic torque will be varied) need to be added. Nvis 7022 consists of good quality digital panel meters to obtain precise results. Dec 5, 2009. Jenkins Gen3 Motor Test Systems are designed with selectable voltage control and improved safety features. As a series DC motor can destroy itself due to high speed at no load. APPARATUS REQUIRED: S.No. The determination losses and efficiency of a dc machine are done by performing a brake on the shaft through belt and pulley arrangement. V) Total output power,P2= (Torque X Speed)/9.55 VI) Power input,P1=Voltage X Total Current VII) Efficiency =P2/P1. No Load Test of an Induction Motor. This example shows a model of a shunt motor.
NO LOAD AND LOAD TEST ON A DC SHUNT GENERATOR . #11. you would test your insulation with a megger. Abstract: In this paper discussed about load test of DC series and shunt motor. Load test on DC shunt and compound motor. (1.)
Therefore, compound DC motor can be used for almost all the applications where both series and shunt motor combined can be used. Copper Few PRECAUTIONS: 1. Introduction: The shunt motor is different from the series motor in that the field winding is connected in parallel with the armature instead of in series. DC Load Test riyas.pdf from ELECTRONIC 125 at Thiagarajar College. Dismantle dc motor using collected tools 3. No Load Test is an indirect method used for determining the efficiency and also to determine the circuit parameters of the equivalent circuit of the three-phase induction motors. Load Test The load testing of DC machine is needed to determine the rating of a machine. When we run a machine, then some energy is lost in the machine, which converts into the heat and cause temperature rise. Motor Test Equipment Magtrol offers three types of Dynamometers, each with a different braking system to absorb load: hysteresis, Eddy-current and powder. When the motor is connected across the supply mains without load, it draws small current from the supply mains. Load test on DC series motor. 2. DC Series motor With Loading Arrangement 1HP, 230V, DC & 1500 RPM. The load testing of DC machine is needed to determine the rating of a machine. Input to motor = V I watts. The load characteristic. 3. Torque Vs. Educational Bench Top Model with schematic diagram of the test circuit engraved on the panel. The mechanical load on the DC motor is dependent over the electrical load applied to the output terminal of the generator.. HOPKINSON TEST :- Hopkinson's Test is another useful The most important performance tests to be conducted on the dc machine are: The magnetization or open-circuit test. Therefore from equation (2), View 1. 7. Fig. Armature current Vs torque (3.)
3. by Kiran Daware DC Machines.
The current in the external resistance is very low, hence the losses occurring in the additional resistance is quite small. It is an indirect method of testing a dc machine performed without actually loading the machine. The arrangement for performing a brake test on a dc motor is shown below. In load test on dc series motor, the motor should be activated on load condition because if the motor can be activated on no load, then it will achieve an A 460 V series motor runs at 500 rpm taking a current of 40 A. Transcribed image text: Load Test of a DC Series Motor Equipment/Software: 1. This videos is done by Mr.J.Kandasamy.M.E(Assistant Professor) PPG INSTITUTE And E of course is K phi f omega; also torque equal to K phi f I a. As increases I a, armature reaction increases but its effect is negligible compared to increase in E. But for high load current, saturation occurs and flux remains constant. First off, for series motors, you need to wire the field in series with the armature. 3. It is a machine whose winding is associated in series with the armature winding of the motor. LOAD TEST ON DC SERIES MOTOR AIM: To conduct load test on DC Series Motor and to find efficiency. Equivalent circuit parameters are armature resistance Ra = 110 Ohms, field resistance Rf = 2.46KOhms, and back emf coefficient Laf = 5.11. Hopkinsons test on DC motor generator set. The open-circuit test is performed on the transformer. Without feedback, no adjustments are made as load increases. Firs the tests were performed on DC Shunt Motor, then DC Series Motor, and then nally DC Generator. Let V = Supply voltage in volts. 1 Characteristics of d.c. series motor. Field test is the method to calculate the efficiency of DC Series Motor and Generator at any desired load. Components of the shunt motor are the armature, labeled A1 and A 2, and the field, labeled F1 and F2. 1 Characteristics of d.c. series motor. The motor should be started and stopped with load PROCEDURE: 1. approximate ly 2 times the rated load torque. The eld produced by the stator current is stationary with respect to stator. Regulating the speed of series motors is also not an easy process to implement. This paper shows measurement of Efficiency of dc shunt and series motor. When we run a machine, then some energy is lost in the machine, which converts into the heat and cause temperature rise. 2012-07-03 14:43:46. c. (1 / Ia2) d. (1 / Ia) View Answer / Hide Answer. 5. 2,098. Built on the principles of safety, simple operation and dependable service, our systems reduce your teams exposure to danger, while keeping your data from all Jenkins test equipment in one place, and readily available. GENERATOR LOAD :- A generator is directly coupled to the DC motor shaft as the generator load increases then automatically speed decreases so the mechanical load varies on the shaft of the DC motor . 1. The terminal characteristics of a series dc motor is very different from that of the shunt dc motor. The speed of the DC motor can be increased beyond the no load speed by inserting an external resistance in the shunt field circuit. Regenerative braking is used to control the speed of motors driving loads such as in electric locomotives, elevators, cranes and hoists. Copper Few Connecting 3 Wires PRECAUTIONS: 1. Ia~0.
Field Test on dc series machines. As increases I a, armature reaction increases but its effect is negligible compared to increase in E. But for high load current, saturation occurs and flux remains constant. Fig. These are explained below for each type of DC motor. Armature current Vs speed (2.) This is a direct method of testing the motor. Turn off the DC power supply and remove any series resistance from the load generator. 6. This test is cannot be performed with DC SERIES MOTOR, since on no load series motor will attain such a high speed that it will get damaged and secondaly this test is The determination of the efficiency curve.
This answer is: motor, the speed control varies the frequency of the power supplied to the motor to change the speed. LOAD TEST ON DC SERIES MOTOR AIM: To conduct load test on DC Series Motor, to find its characteristics and efficiency. Wiki User. Load Torque: For a fixed voltage, the speed of the motor is inversely affected by the load. MATLAB Theoretical Background The circuitry of this motor includes an armature in series with an inductive field winding. Now suppose the DC Series Motor is started at no load then DC Series Motor will take very small current from the supply mains as the input power needed is to only overcome the no load losses. 4. Now assuming the terminal voltage of DC Motor to be V t and I L to be the load current then, Power input to the DC Motor = V t I L. Thus the efficiency of DC Motor can be calculated as below. Due to this series arrangement, the motor is able to produce more starting torque compared to other motors. 6. Search: Brushless Motor Thrust Chart. These motors, like other DC motors, feature both a stator and a rotor. Efficiency Panel For Load Test Of DC Series Motor Specifications: 1. Retardation test on dc shunt motor. resistors. Regenerative test on dc shunt machines.
Therefore, Swinburne's test is only applicable for dc shunt and small series machines. The purpose of a portable DC load bank is to accurately simulate the load a power source will encounter during actual operation. Load test on dc shunt motor to draw speed torque and horse power efficiency characteristics. 7. Series motor armatures are usually lap wound. Usually like A1 to B+, A2 to S1, & S2 to B-. Buy Equipment or Ask for a Service. It is supplied with one MS powder coated Electrical panel fitted with high insulation Bakelite sheet. The data was recorded in the Table2.2. (Refer Slide Time: 00:23) Few classes we have derived the torque speed characteristics of a DC series motor. 2. Motor. In such case, due to the armature reaction E starts decreasing as shown by dotted line in the Fig. SEMESTER 2013/2014-1 Page | 2 EE3010 [Lab 5] UEL ID: U1060761 4. When excited by dc current air-gap ux distribution created by this winding is symmetric about the center line of the eld poles. Generally, three characteristic curves are considered important for DC motors which are, (i) Torque vs. armature current, (ii) Speed vs. armature current and (iii) Speed vs. torque. For brushes/commutator, your best check is visual.
We can write induced voltage E plus I a. An eddy current load will be used as the load and the performance of the motor before and after load will be analyzed and studied. Swinburnes test and speed control of DC shunt motor. Speed control of dc shunt motor by armature and field control. In both cases, the speed control is simply controlling the input to the motor and the motor will respond to the load with a specific speed. DEPARTMENT OF EEE LAB MANUAL CLASS SEMESTER SUBJECT CODE SUBJECT : II YEAR Collect materials 2. You can check your continuity with an ohm meter. Series DC Motor Components of a series motor include the armature, labeled A1 and A2, and the field, S1 and S2. 12 Volts max. [4] 2.2 DC Series Motor Experiment Set-up Figure 3: This is how the experiment was setup for DC series motor. Motor is copper wound with class b insulation. Swinburne's Test on dc motor. Nvis 7022 also includes experiments such as Open Circuit Characteristic, Internal and External Characteristic of DC Series Generator in an easiest manner. RAJALAKSHMI ENGINEERING COLLEGE THANDALAM 602 105. The field windings make up the stator, which is the static element of the motor.
Motor Output = (S1 S2) x r x9.8 Watt. Efficiency= (2*3.14*N* (W-S)*9.81*r)/ (60*V*I) The efficiency of dc machines obtained from brake test is The reason is that the speed of series motors varies greatly with varying load.