Learn techniques for DC voltage measurement and checking amplitude of electrical noise present; AC voltage measurement to determine amplitude andfrequency; measuring digital signals for amplitude, frequency and distortion including duty cycle wave forms as shown below.
Learn to measure AC waveforms for amplitude, frequency and reference to ground. Learn to measure digital waveforms for amplitude, frequency, reference to ground, pulse width or time duration.
Section 7 is devoted to practice in analyzing wave forms and detecting when a misadjusted lab scope control may be the reason a wave form appears incorrect on the CRT but is correct in the circuit. Sega Contra Game Pc. A typical house wiring circuit is shown in fig. Fig 2.
The two copper strips, known as bus-bars, fixed in a distribution board of hard wood or metal case are connected to the supply main through a linked switch so that the installation can be switched off as a whole from both the poles of supply if required. In such cases main distribution board controls the circuit to each sub- distribution board from which the sub-circuits are taken, as shown in fig.
For determination of load of an installation the following ratings maybe assumed unless the values are known or specified. There are number of methods of installing a wire system. Our house is Phase P and other is neutral. As we know the fuse and M. We make connection and get result as shown in Observation Table. Connections should be right and tight. Do not touch any wire.
Do not keep any joint open. Use M. To wiring for a lamp to be controlled from two positions stair-case wiring. Apparatus Required Rating Type Quantity 1. Lamp Holder 6Amps, volts 1 2. Lamp Watts,15 Watts 1 3. Switches Two-way 5 Amps, Volts 2 4. Connecting Leads - - As Reqd. Screw Driver - - As Reqd. In staircase wiring ,bulb used for lightening the staircase can be switched ON and OFF from both sides, upstairs and downstairs , for this kind of arrangement circuit is shown in fig.
Now if position of any of the switch is changed the phase is applied to one end of bulb and it becomes ON. Now if the position of other switch is also changed, the bulb becomes OFF as phase gets applied at both the ends of bulb. Now if again position of any off switch is changed ,the bulb becomes ON again. A Different arrangement for stair-case wiring is shown in fig. In fig a Neutral N is directly connected to the bulb and for Phase P , cross connection are made in the two switches.
In fig. In cross connection, if both switches have same position i. Whereas in straight connection; if both switches have same position of either switch has been changed, lamp change its position. Stair-case wiring and a room wiring. No any connections should be loosed. To study the construction and basic working of ceiling fan and connections of ceiling fan with regulator.
It is provided with a device for suspension from ceiling of a room so that the blades rotate in a plane to give uniform air circulation in the room. According to the electric motor used, ceiling fans can be classified as follows: 1.
AC fans use single phase squirrel cage induction motor. Motor 2. Capacitor 3. Blades 4. Canopy 5. Ball-bearings 6. Speed regulators Fig 3. Regulator may be electronic type or resistance type. Electronic type regulator has negligible power loss and compact size. But in the case of resistance type, resistances are connected in series with the circuit; this may cause power loss as heat.
In table fan one permanent split capacitor run PSC motor is the heart of a fan. This motor consists of two windings one as starting winding and other as running winding. Starting winding of this motor has high resistance and low reactance but running winding has low resistance and high reactance. One capacitor is connected in series with the starting winding and whole of this circuit is put in parallel across running winding. In the case of ceiling fan these two windings are placed in stator in the inner side of the fan.
Rotor has no winding; it is the outer body of the fan. Ceiling fan motor operates just in opposite manner as compared to general motor. That is actual rotor of the motor is blocked and the stator is free to rotate. So ceiling fan runs in anticlockwise direction.
At the same time table fan motor is operated as normal case and so it runs in clockwise direction. Capacitor connected in series with the starting winding should be value 2. Pyranel insulated foil paper capacitor is using for this purpose.
It helps to provide a split phase effect from single phase AC supply. Fig 3. Running winding 2. Starting winding 3. Earth test of fan 4. Do not touch any live wire or contact. Make the proper connection as given in circuit diagram and it should checked by lab in charge before switch ON the supply.
Save the winding of fan for any damage. Handle the equipments carefully, which are used in the experiment. Use only W lamp for testing purpose for saving any damage to windings due to high current.
Name of Apparatus Type Range Quantity 1. Techo-meter Digital rpm 1 6. When power electronics converters are used three phase a. In this sense, we call them single phase induction motors. To be self-starting, the induction machine needs a travelling field at zero speed. This in turn implies the presence of two windings in the stator, while the rotor has a standard squirrel cage. The first winding is called the main winding while the second winding for start, especially is called auxiliary winding.
Single phase IMs may run only on the main winding once they started on two windings. A typical case of single phase single- winding IM occurs when a three IM ends up with an open phase. The power factor and efficiency degrade while the peak torque also decreases significantly.
Three types of single-phase induction motors are in use today: Fig 4. The auxiliary winding has a higher ratio between resistance and reactance, by designing it at a higher current density, to shift the auxiliary winding current I ahead of main winding current I Figure 4. This travelling field induces voltages in the rotor cage whose currents produce a starting torque which rotates the rotor from to a clockwise on Figure 4.
Once the rotor catches speed, the starting switch is opened to disconnect the auxiliary winding, which is designed for short duty. The starting switch may be centrifugal, magnetic, or static type. During running conditions, the split-phase induction motor operates on one winding only and thus it has a rather poor power factor. Complete symmetrization of the two windings m. An improvement in starting and running torque density, efficiency and especially in power factor is brought by the capacitor presence.
Start winding means of design that ring a continuous copper loop around a small portion of the motor pole. Make connection as shown in fig. Put input voltage at Zero. Now slowly vary input voltage and measure the speed by tachometer. Record the value of speed at various voltage. No Input Voltage Speed rpm 1 50 2 3 4 5 6 RESULT: Study the construction and basic working of ceiling fan, single phase induction motor and three phase squirrel cage induction motor.
Connect ceiling fan along with regulator and single phase induction motor through auto-transformer to run and vary speed. Connection should be right and tight. Main switch , starter and motor should be earthed. Use of proper range of voltmeter and ammeter. The motor is also made of silicon steel stampings core slotted in which copper or aluminum bars are inserted and shorted by copper or aluminum short circuiting rings on both sides. The body is made of cast iron on which channel given by a fan fitted on the shaft of the motor on rear side.
The fan is covered by a sheet steel cowl. The connections of stator winding is made inter is star or in delta. Title: diploma ee 5th semester electrical work shop lab manual Page Link: diploma ee 5th semester electrical work shop lab manual - Posted By: ajujoy Created at: Sunday 16th of April AM. The torque meter can be used to drive or brake an electric machine in order to measure its characteristics.
It consists of a DC machine, the stator of which is mounted in bearings so that its torque reaction is transmitted to a pressure sensor. The range of the torque me Title: diploma casp lab in electrical and electronics tasks Page Link: diploma casp lab in electrical and electronics tasks - Posted By: skpbravo Created at: Sunday 16th of April AM.
Provide technical assistance and resolution when electrical or engineering problems are encountered before, during, and after construction. Assemble electrical and electronic systems and prototypes according to engineering data and knowledge of electrical principles, using hand tools and measuring instruments. Install and maintain electrical control systems and solid state equipment.
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