AC tachogenerator DC tachogenerator The AC tachogenerator is use to measure speed only in one direction only. The DC tachogenerator is. A.C. Tachogenerator • 2. D.C. Tachogenerator; 6. CONSTRUCTION • An Armature is rotating type & this magnet is fixed type. • Armature is. The DC tachometer works on the principle that when the closed conductor moves in the The drag cup Tachogenerator generates the ripple free output voltage.

Author: Dujinn Dabei
Country: Norway
Language: English (Spanish)
Genre: Education
Published (Last): 16 June 2006
Pages: 15
PDF File Size: 9.79 Mb
ePub File Size: 12.2 Mb
ISBN: 796-7-30788-310-7
Downloads: 15908
Price: Free* [*Free Regsitration Required]
Uploader: Nikoramar

When not connected to a load resistance, generators will generate voltage roughly proportional to shaft speed. The rotation induces the emf in the coil. A generator specially designed and constructed for this use is called a tachometer or tachogenerator. Tachogenerators Chapter 9 – Electrical Instrumentation Signals.

The below mention circuit is used for measuring the speed of the rotor by considering the amplitude of the induced voltage. Published under the terms and conditions of the Design Science License.

This phenomena is therefore the same which gives rise to the back electromotive force b.

Follow Us likes followers subscribers. Advertise with Ads Link x In this post, i am interested in covering the details about how to measure flow using Orifice meter.

The induces voltage is proportional to the speed of the rotation. The magnitude of the induced emf is proportional to the shaft speed. Tachogeneratlr armature of the D.

The commutator converts the alternating current of the armature coil to the direct current with the help of the brushes. The mechanical tachometer measures the speed of shaft regarding revolution per minutes. Figure 1 Typical transfer characteristic of tachogenerator.


The rotor is made of the highly inductive material which has low inertia. The commutator collects current from armature conductors and converts internally induced a. Design challenges and improvement techniques for SAR driver circuit Design challenges and improvement techniques for SAR driver circuit. Leave a Reply Cancel reply Your email address will not be published. Mechanical and electrical are the two types of the tachometer.


The polarity of output voltage indicates the direction of rotation. The DC tachometer gheory uses the commutator and brushes which have many disadvantages. The input is provided to the reference winding, and the output is obtained from the quadrature winding.

C tachogenerator is shown in below figure. The develops EMF is directly proportional to the speed of the tacjogenerator. The polarity of the induces voltage determines the direction of motion of the shaft. The AC tachometer has stationary armature and rotating magnetic field.

Permanent magnet, armature, commutator, brushes, variable resistor, and the moving coil voltmeter are the main parts of the DC tachometer generator. The tachogenerator is a direct-type velocity transducer. These variations are usually amply documented in the manufacturer data sheets and do not present a problem. And i am starting it from the scratch. Both of the latter two drawbacks are caused by the presence of the commutator in the d.

D.C Tachogenerators – Instrumentation and Control Engineering

The armature of the DC generator revolves between the constant field of the permanent magnet. By measuring the voltage produced by a tachogenerator, you can dx determine the rotational speed of whatever its mechanically attached to. The nonlinear relationship obtains between the output voltage and input speed when the rotor rotates at high speed. Basic Principle of Hot wire Anemometer When an electrically heated wire is placed in a flowing gas stream, heat is transferred from the w Depends on the natures of the induced voltage the electrical tachometer is categorized into two types.


The relative motion induces the EMF in the coil which is placed between the constant magnetic field of the permanent magnet. The amplitude and frequency of the induced emf are equivalent to the speed of the shaft.

The AC tachometer generator designs for reducing the problems. Although a voltage divider could theoretically be used with a tachogenerator to extend the measurable speed range in the volt scale, it is not advisable to significantly overspeed a precision instrument like this, or its life will be shortened. Tachogenerators can also indicate the direction of rotation by the polarity of the output voltage. The armature of the tachogenerator is coupled to the machine whose speed is to be measured.

Now as the field of tachogenertaor permanent field is fixed, the e. The constant of proportionality K t is generally linear within a large dynamic range but does vary in relation to: