Let’s take the example of a 230-400V electrical motor. Example of star and delta connection. In delta connections each winding has the same voltage level. In star connections the voltage is distributed over the three windings.
The auxiliary winding is connected through a capacitor only during starting. So I’m thinking that the motor may have to Capacitor-start motors, such as used in refrigerators. The concern is that there is a capacitor for the motor. You should see that there is a separate motor winding for high speed. Double check your connections using the fan wiring diagrams.
Electric Motor Winding Connections Series Capacitor Is
Maximum torque occurs for a capacitance such that the auxiliary current leads the main current by (½π = α)/2. The auxiliary winding is a so-called shading coil consisting of an uninsulated short-circuited copper strip embedded into one of the main poles and spanning about one-third of its pitch.The direction of motion in motors of types 1, 2, and 3 can be changed by reversing the connections of either the main or the auxiliary windings.MG Say PhD, MSc, CEng, FRSE, FIERE, AGCI, DIC, JF Eastham, in Electrical Engineer's Reference Book (Sixteenth Edition), 2003 Capacitor split-phase motorA greater phase difference (ϕ m − ϕ s ) can be obtained if a series capacitor is substituted for the series resistor of the auxiliary winding. 4.Shaded-pole motors, such as used in fans. The auxiliary winding is connected only during starting. The auxiliary winding is wound with fewer turns and much smaller size of wire than that of the main winding, so that it has a considerably greater resistance-to-reactance ratio.
If a single capacitor is used for both starting and running, the starting torque is 0.5–1 times full-load value and the power factor in running is near unity.Fig. Ideally, however, the value of capacitance for running should be about one-third of that for the best starting. For economic reasons the capacitor is as small as is consistent with producing adequate starting torque, and some manufacturers quote alternative sizes for various levels of starting torque.If the capacitor is left in circuit continuously ( capacitor-run) the power factor is improved and the motor runs with less noise.
20.9, therefore it will not be repeated here for the sake of simplicity. Note this phase angle displacement may vary under different speeds since the capacitance in the auxiliary winding is subject to the control frequency.The control block for this case is almost the same as in the earlier case shown in Fig. (20.9a), (20.9b).Unlike the earlier case without the running capacitor in the auxiliary winding, since the running capacitor is able to make the impedance of the auxiliary winding capacitive and as a result, the main winding current and the auxiliary winding current have a phase displacement of around 90 degrees, and the main winding voltage V main and the auxiliary winding voltage V aux can be kept in phase. The main winding voltage and the auxiliary winding voltage can be presented in Eqs.
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