classification of electrical measuring instruments ppt

... ``,`,`,,,,`,,,,`,```,``````,`-`-`,,`,,`,`,,` -ELECTRICAL APPARATUS FOR EXPLOSIVE GAS ATMOSPHERES –Part 10: Classification of hazardous areas 1 General 1.1 Scope This part of IEC 60079 is concerned with the classification of hazardous ... process pressure and the geometry of the source of release The size of a cloud offlammable gas or vapour is determined by the rate of flammable vapour release and therate of dispersion Gas and vapour ... of one opening type C adjacent to a hazardous area and one opening type B in series Table A.1 – Effect of openings on grade of release Zone upstream of opening Opening type Grade of release of

Ngày tải lên: 25/12/2013, 10:41

... core loss is one of the most difficult to estimate for two reasons: 1 The cataloged data of electrical steel sheets are measured for a rectangular shape in a uniform magnetic field Electrical steel ... hand, a method proposed to express the B-dependency of the hysteresis loss changes the values of the exponentα and of Kh for different levels of B in equation (1) [8] Different levels defined in ... loss of a turbine generator includes various losses besides those produced in the laminated steel sheets of the core We have also analyzed the causes of the losses in these sheets Part of these

Ngày tải lên: 02/07/2014, 09:20

... efficiency of the turbine the speed of the generator is adapted to the hydraulic conditions resulting in typical speed ranges of generators from 67 to 1,500 rpm The corresponding number of poles of the ... for a given set of weighting factors k including the set of reference machines is derived from equation (4) An optimized set of weighting factors k can be found by minimization of the mean quadratic ... reference and sample machines For all of these machines, a new electrical recalculation is performed using not only the original electrical calculation, but also a set of drawings with detailed information

Ngày tải lên: 02/07/2014, 09:20

... to verify the electrical parts of the model and hence served its purpose. However, in any electromechanical system the interaction between the electrical and mechanical system are of interest. ... The electrical analogy of this would be reactive power. At resonance no reactive power is supplied to the device from the sea. When the device is operating at off- resonance pointsa method ofsupplying ... Element Analysis of PMSM with Buried Magnets 53 The only difference of these two motors is in their internal rotor structure. Areas of the magnets are same and in the str ucture of Fig. 3 magnets

Ngày tải lên: 02/07/2014, 09:20

... The goal of this study is to establish the effect of magnetostriction and magnetoelastic coupling on the vibrations and noise of rotating electrical machines Results about the effect of coupling ... Introduction The effect of magnetostriction and inverse magnetostriction (Villary effect) on the vibrations and acoustic noise of rotating electrical machines is still a subject of controversy Indeed, ... vibrations of rotating electrical machines [1,2]; others claim that the magnetostriction can be ignored [3] We investigate the problems of magnetoelasticity and magnetostriction by means of coupled

Ngày tải lên: 02/07/2014, 09:20

... analyze the validity of each method with accuracy The fixation of a stator yoke allows to observe the modifications of the mechanical behavior Introduction The study of electrical machine noise ... Developments of Electrical Drives, 225–236. 2006 Springer. Trang 4226 Lecointe et al.Table 1 Used variables Symbol Quantity R c Average radius of the yoke e c radial thickness of the yoke L e length of ... the third one is composed of a statoric yoke made of steel which is equipped of two welded feet (Fig 5) Table 3 presents the dimensions of the structures The geometry of the cylinders is quite

Ngày tải lên: 02/07/2014, 09:20

... curve of the IM, used in the observer with and without included magnetic saturation (Fig. C1, Appendix C). Figure 6. Stator currents i sd and i sq . II-10. Impact of Magnetic Saturation of Induction ... Consideration of magnetic saturation in the IM model substantially improves its accuracy, leading to a more efficient and consistent synthesis of the control algorithm, observer, and estimator of load ... improved behavior of the controlled IM is more adequately calculated value of the rotor flux linkage when magnetic saturation is considered in the observer design. Appendix A Elements of matrices C,

Ngày tải lên: 02/07/2014, 09:20

... inverted connection of coils belonging to adjacent teeth of the same phase (contro- verse coils). By adopting the representation of Fig. 1 (right) to specify the winding sense of each coil around ... including pole pitch can be summarized as air-gap length (g 0 ), height of magnet (h m ), height of slots (S h ) (or number of turns in slots), which are flexible to the normal direction. With the ... period, the greatest-common-divider (GCD) of the pole pitch and the tooth pitch (τ c , same with coil pitch) Reduction of core detent force Reduction of the core detent force can be done by giving

Ngày tải lên: 02/07/2014, 09:20

... and generic model of linear inductance A symbolic and generic model of the ideal coil is given in figure 2.2. With the model of figure 2.2 we will now simulate the time-response of a coil in reaction ... flux Ψ by L. Figure 2.3. Transient response of inductance 32 FUNDAMENTALS OF ELECTRICAL DRIVES 2.3 Coil resistance In practical situations the resistance of the coil wire can usually not be ne- glected. ... function of the module is described as i (ψ), which expresses the current of the coil as a function of the coil flux. The terminal equation (2.8) remains unaffected by the introduction of saturation,

Ngày tải lên: 09/08/2014, 06:22

... as Trang 3Figure 5.2 Phasor diagramof phasors i, u An observation of figure 5.2 learns that we can also represent the voltage phasor in terms of the vector sum of the two phasors u re = ˆu cos ... the power which is of the form P =
 u  Note that the superscript ∗ indicates the conjugate of a vector The validity of this expression is readily verified upon substitution of equation (5.24), ... these concepts with the aid of an example where we assume a sinusoidal current time function of the form It is convenient at this stage to introduce a phasor representation of the variables u (t)

Ngày tải lên: 09/08/2014, 06:22

... rather than providing a variety ofchoices, some of which are better than others but none of which isexactly what they want Unfortunately, the internal divisions ofthe company that turn out the ... believe that relationships are essential to the long-term suc-cess of their business, these sources of value are largelyoverlooked and often inadequately managed This neglect oc-curs despite the fact ... according to the Andersen–DYG study, execu-“Nearly three-quarters of the market value of today’s most cessful companies is built upon sources of value that can be clas-sified as relationship based or

Ngày tải lên: 10/08/2014, 11:20

... this type of financing. Thus, he offers you information about a competency that may help you in attaining customers 126 Part Two ❘ Purposeful Collaboration 7 ❘ Measuring the Value of Every Relationship ... understanding of Len’s Future Relation- ship Value (much greater than Sharon’s), but it unnerves you a lit- tle. Unless you can offer Len something of value and increase the rhythm of the relationship, ... of the value in the relationship you could receive but are not currently benefiting from 7 ❘ Measuring the Value of Every Relationship 1 37 11 ❚ Identifying and measuring

Ngày tải lên: 10/08/2014, 11:20

... enterprise, the not-for-profit saw great value Trang 5in the currencies the farm had to offer; and because of the trustbuilt through the history of the relationship, the not-for-profithas agreed to iterate ... configures its software: neces-The traditional way to configure the software was bymodule, or by functions, or by departments We had fi-nancial software, manufacturing software, purchasingsoftware, ... rather than a discrete set of financial soft-ware So that process might include financial software,salesforce automation software, customer manage-ment, price management software—and that’s nowthe

Ngày tải lên: 10/08/2014, 11:20

... determines the relative priority of all your rela-tionships The scorecard provides a wealth of informa-tion, so analyze that too 10 ❘ How You Do Business in the Era of Collaborative Business 193 ... provide, you must build the required level of trust through the activities associated with each level of collaboration You do this by constructing a se-ries of value propositions that get each party ... has better information Thus, the implications of our new methodologies and tech-nologies are profound First, you can exponentially increase the level of information at your fingertips for making

Ngày tải lên: 10/08/2014, 11:20

... Trang 1THE UNIVERSITY OF TECHNICAL EDUCATION HO CHI MINH CITY FACULTY OF ELECTRICAL & ELECTRONICS ENGINEERING DIVISION OF INDUSTRIAL ELECTRICSITY Subject : General rules of electrical installation ... understand more detail of electrical installation design and I have an good job when I graduated. -Content : + +Definition of voltage ranges +Standards +Quality and safety of an electrical installation ... testing of an installation +Periodic check-testing of an installation +Environment Trang 3Definition of voltage rangesIEC voltage standards and recommendations The nominal voltage of existing

Ngày tải lên: 02/08/2013, 01:25

... not only the number of cross-points of the switching network but also the cost of wave-length converters We often have to make trade-offs between the connecting capability of a WDM optical switching ... minimum number of crosspoints (a) The diagram of the concentrator (b) The crosspoint layout of the concentrator (c) The diagram of the reverse concentrator (d) The crosspoint layout of the reverse ... Hardware Cost of a Single Stage WDM Switching Net-work Since the number of crosspoints of a WDM optical switch-ing network is simply that of its crossconnect, we can analyze the number of crosspoints

Ngày tải lên: 24/10/2013, 04:15

... method of partially known system and shows its application result to control of a two-wheeled welding mobile robot The controlled system is designed using Lyapunov stability The effectiveness of ... Motion Control of Mobile Robot for Lattice Type of Welding Line”, KSME International Journal, Vol 16, No 1, pp 83-93, 2002 [5] B.O Kam, Y.B Jeon and S.B Kim, “Motion Control of Two-Wheeled Welding ... Feedback Control of Vehicles with Two Steerable Wheels”, Proc of the 1996 IEEE Int Conf on Robotics and Automation, pp 3105-3110, April 1996 [15] Y Zheng and P Moore, “The Design of Time-Optimal

Ngày tải lên: 10/12/2013, 13:16

... condi- tions), knowledge of the density of one of the carrier types (e.g., of p) allows direct deter- mination of the density of the other (e.g., n = n 2 i /p). Values of n i vary considerably ... semiconductor crystals, the density of such scattering sites is small relative to the density of silicon atoms. As a result, removal of the silicon atoms through use of the effective mass leaves a somewhat sparsely ... overview of many of the semiconductor materials in use. To organize the information, the topic is developed from the perspective of the factors contribut- ing to the electronic behavior of devices...

Ngày tải lên: 25/01/2014, 15:20

... manufacture of electrical equipment, the job site, and the installation of electrical systems. Many of these stan- dards are focused on safety issues, such as the elimination or avoidance of hazards ... owner. Electrical specifications and electrical drawings are integral parts of the contract requirements for the performance of electrical work. Because specifications are a significant part of a ... drawing of a section through the wall of an office warehouse. It provides details of how and where hanger fittings and boxes are to be placed between a column and insulation to support a run of bus...

Ngày tải lên: 25/01/2014, 23:20