Motors - TEA Machine Components Inc.

MOTOREN
Technology
Induction Motors
NECKAR
All induction motors operate according to
a uniform principle: The mechanically stationary
“Stator“ produces a rotating magnetic
field which is synchronised exactly
with the frequency of the power supply.
The rotor is made of low-loss magnetic
steel which is surrounded by a cage made
of short-circuited metal bars, (therefore also
the name “squirrel-cage rotor “).
During operation the stator induces a
(therefore “induction motor“) torque produced
magnetic field in the rotor, as long
as this turns more slowly than the stator
magnetic field. The difference in the speed
of rotation between stator and rotor is
called “slip“. The greater the slip, the
greater also the induction and therefore
the torque of the motor.
This behaviour leads to a stabilisation near
the nominal point, which with the right design
leads to stable behaviour without the
assistance of electronic controls.
Induction motors are an important part of
the NECKAR-MOTOREN- Programme. A
single-phase capacitor motor normally has
a lower starting torque as the rated torque.
This should be taken into consideration
during design.
This is just the opposite to 3-phase current
motors. Therefore the 3-phase current motor
is preferred for applications with difficult
start up.
The following table shows the relationship of the starting torque to the rated torque.
Single-phase motor
3-phase motor
2pole 0.60 x M rated 1.2 x M rated
4pole 0.70 x M rated 1.3 x M rated
8pole 0.85 x M rated 1.6 x M rated
The typical torque characteristics can be seen in Fig. 1 and 2.
The efficiency of these precision motors are as follows
Single-phase motor
3-phase motor
2pole up to 63 % up to 72 %
4pole up to 52 % up to 56 %
8pole up to 29 % up to 35 %
The resulting rated speeds for both types are then:
You have the following benefits when
using Neckar-Induction motors:
With 3-phase current motors simple
connection to the 3-phase supply.
With capacitance motors simple connection
to the lighting circuit.
High specific power volume.
2pole 2600–2750 min –1
4pole 1200–1300 min –1
8pole 600– 650 min –1
Rotation reversal by simply changing the
poles.
Extremely long service life only dependent
on ball bearings.
Because of our modular design all motors
can be combined with various gears
detectors, brakes etc.
Extremely quite running in all load
phases.
you, too, will find your made-to-measure
drive
Md=Ncm
K 662
Md=Ncm
K 662
M stall
M start
M stall
M start
M rated
Rated operation c=2.5 µF
Rated operation λ
Rated operation ∆ c=3 µF
M rated
M start
Figure 1 Figure 2
For data sheets see page 27–38
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