Eaton DS7 Series, Manual

Page: 29 / 240

1 Device series DS7
1.13 Selection criteria
DS7 Soft starter 09/16 MN03901001Z-EN www.eaton.com
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1.13 Selection criteria
The soft starter DS7
③
is selected on the basis of the supply voltage U
LN
of
the supply network
①
and the rated operational current of the assigned
motor
②
. The circuit type ( Δ /  ) of the motor must be selected according to
the supply voltage ① . The rated output current I
e
of the soft starter must be
greater than/equal to the rated motor current.
Figure 9: Selection criteria
When selecting the drive, the following criteria must be taken into account:
• Type of motor (e.g.three-phase asynchronous motor)
• Mains voltage = rated operating voltage of the motor (e.g. 3 AC ~ 400 V),
• Rated motor current (recommended value, dependent on the circuit type
and the power supply),
• Load torque (quadratic, linear),
• Starting torque,
• Ambient air temperature (rated value +40 °C).
￫
With heavy starting duty motors, the soft starter must be
overdimensioned in terms of its overload capacity.
￫
In the case of single-phase AC motors ( ￫ page 20), the
selection must be based on the mains voltage (= the motor’s
rated operating voltage) and the rated motor current for the
specific line frequency.
230 / 400 V ∆ / 
4.6 / 2.6
1.1 kW
0.81
min -1 1430 50 Hz
A
②
③
①
U, I, f
cos ϕ