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close this bookCircuits, Formulas and Tables Electrical Engineering - Basic vocational knowledge (Institut für Berufliche Entwicklung, 201 p.)
close this folder4. Electrical Machines
close this folder4.2. Three-phase Machines
View the document4.2.1. Three-phase Generators
View the document4.2.2. Three-phase Motors

4.2.1. Three-phase Generators


Three-phase generator with exciter (A)


Three-phase generator with exciter (B)

4.2.2. Three-phase Motors

Mains voltage designations

3 N 220V/380V 50 Hz


1 N 220V 50 Hz


Three-phase motor with star-delta connection (star connection)


Three-phase motor with star-delta connection (delta connection)


terminal boards (clockwise sense of rotation)


terminal boards (anti-clockwise sense of rotation)


terminal boards (clockwise sense of rotation)


terminal boards (anti-clockwise sense of rotation)


Three-phase motor with drum switch for clockwise and anti-clockwise rotation


Three-phase motor with lever commutator for star-delta starting


Three-phase motor with dram switch for star-delta starting


Three-phase motor (slip ring rotor) with rotor starter in star connection


Three-phase motor (slip ring rotor) with rotor starter in delta connection and controller drum for clockwise and anti-clockwise rotation


Three-phase motor with protective motor switch for undervoltage tripping, thermal tripping and magnetic tripping


Three-phase motor (slip ring rotor) with rotor starter and protective motor switch for manual and magnetic tripping


Three-phase motor with control acknowledging switch and protective motor switch


Three - phase motor in Dahlander pole-changing connection


Three-phase motor in “with Dahlander pole-changing connection”


Three-phase motor in “reverse Dahlander pole-changing connection”


Rotor-fed three-phase shunt-wound commutator motor


Three-phase motor at the single-phase mains (A)


Three-phase motor at the single-phase mains (B)

explanations to the wiring diagram
c1 operating capacitor, c2 starting capacitor

Frequently it is necessary to connect three-phase not ors to single-phase mains. In this connection, the following disadvantages must be taken into account. The rated output (see rating plate) will be reduced to 80 % to 65 %.

The rated torque will be reduced to 30 %.

The output or power can be calculated according to the following equation:

C = capacity of the capacitor in mF
P = power in kW
U = voltage in V
f = frequency

The following approximate values can be assumed when connecting to single-phase alternating current of 220 V:

Power (kW)

Capacity of the Capacitor

0.10

7

1.00

50

2.00

100


Three-phase series commutator motor

1 OFF position
2 starting, operation
3 braking


Single-phase capacitor motor with auxiliary phase


Repulsion motor


Ward-Leonard Control low-loss speed adjustment at the direct-current motor (General wiring diagram)