Low voltage tests on form-wound stators, such as inductance or inductive impedance tests, can detect if the turn insulation is shorted, but not if it is weakened. Only the surge voltage test is able to directly find stator windings with deteriorated turn insulation. By applying a high voltage surge between the turns, this test is an overvoltage test for the turn insulation, and may fail the insulation, requiring bypassing of the failed coil, replacement or rewind.
Electric Machine Parameter and Testing — Part 5 Partial Discharge Test IEC TS For many years, the measurement of partial discharges PD has been employed as a sensitive means of assessing the quality of new insulation as well as a means of detecting localized sources of PD in used electrical winding insulation arising from operational stresses in service. Compared with other dielectric tests i. The PD testing of rotating machines is also used when inspecting the quality of new assembled and finished stator windings, new winding components and fully impregnated stators.
The measurement of partial discharges can also provide information on: points of weakness in the insulation system; ageing processes; further measures and intervals between overhauls. Although the PD testing of rotating machines has gained widespread acceptance, it has emerged from several studies that not only are there many different methods of measurement in existence but also the criteria and methods of analyzing and finally assessing the measured data are often very different and not really comparable.
Consequently, there is an urgent need to give some guidance to those users who are considering the use of PD measurements to assess the condition of their insulation systems. Electric Machine Electric machine — transducer for converting electrical energy to mechanical energy or mechanical energy to electrical energy Types of Electric machines Motors Generators Sensors Electromagnets Electromagnetic Amplifiers, etc.
Easy to predict motor performance Simple, inexpensive control electronics Use of a feedback device is optional Difficult to design brush system Limited availability of the brush system components Very difficult to predict brush life Not a motor of choice for high-performance application Manufacturing cost very low for mass production, when fully tooled. Dielectric Materials Paper Epoxy Plastic. Magnet Wire Copper Aluminum Litz.
Deterioration of Magnetic Properties due to Punching Fully processed material is simply material which has been annealed to optimum properties at the steel mill. This is particularly true for parts with narrow sections, or where very high flux density is required. Conductor The most suitable materials for magnet wire applications are unalloyed pure metals, particularly copper High-purity oxygen-free copper grades are used for high-temperature applications Aluminum magnet wire is sometimes used as an alternative for transformers and motors.
Custom Part Production Manufacturing Capabilities. Grain-Oriented Silcon Steel. Br — 5, — 13, Hc — — 1, MGOe 1. Br — 6, — 10, Hc — — 1, MGOe 1. Br — 3, — 4, Hci — 3, — 4, MGOe 2. Simple Shapes: Arcs, Rect. Br — 8, — 11, Hci — 11, — 21, MGOe — 18 — All dimensions are given in millimeters. By following the prompts, you will be taken through the entire process. Areas marked in yellow are mandatory: voltage, frequency,connection: a wye star or a triangle delta , number of poles, the dimensions of the stator iron, tooth width and number of slots.
The program will warn you if you forgot to write something or you typed in the wrong format. You will not be able to go on to the next page unless all areas have been marked correctly. The program will offer you a list of all possible diagrams 4. Choose one, save or print it. Choose the flux density so that the density in the back-iron, and teeth arewithin permissible limits marked in green.
To calculate the wire size, it is necessary to measure the slot. You have completed the calculations Write down the slot dimensions and the desired number of wires.
The wire-size can be calculated in several different ways the area of an old winding or a slot of a other shape or the cross section of all wires, etc. All details and calculation data can be saved and printed with the earlier diagram. You have already calculated the number ofturns in a slot. Post on Jul Category: Education 3 download.
Three-Phase AC Winding Calculations single-speed windings Kinds of diagrams This calculations program includes all necessary details for rewinding three-phase motors:the type of windings, number of layers, parallel circuits, span and number of turns per coil , number and cross section of turn in a slot, as well as the winding diagram.
The basis also includes about most frequently used diagrams for12, 18, 24, 27, 30, 36, 42, 45, 48, 54, 60, 72, 75and90slots. There are two kinds: a complete diagram for single-layerwindings diagram on the left or internal connections between PPH groupsfor double-layer windings diagram on the right.
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