Download DS7 Soft Starters

2 Engineering
2.1 Selection of devices
2 Engineering
2.1 Selection of devices
The DS7 soft starters can be designed for standard applications according to
the technical specifications provided in the Appendix for standard motors.
A more precise design is required for drives with a high starting torque or
high inertia. The following information must be known for correct selection of
device:
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the overload cycle of the machine,
The startup time for DOL starting or for star/delta starting,
the maximum starting current,
the load cycle as well as
the load that the motor is required to drive.
The values of the moments of inertia must also be known for a more precise
design. These values enable you to select the most suitable soft starter. The
relevant procedure is described in the manual “Soft Starter Design”
(MN03902001Z-EN; previous description AWB8250-1346GB) and applies
generally to all Eaton soft starters. The necessary key data of the DS7 soft
starter series that is also required for this design (rated operational current,
overload capacity, root mean square current at nominal switching frequency)
is provided in the Appendix in the technical data.
2.2 EMC measures
EMC = Electromagnetic Compatibility
The European standard EN 60947-4-2 refers to the limit classes described in
the EN 55011 standard.
No other measures are required for the limitation of interference emission in
accordance with EN 55011 limit value class A (industrial environment).
The devices of the DS7-340… (24 V AC/DC version) series furthermore meet
the requirements of limit value class B (public environment) without any
other measures required.
2.3 Network configuration
DS7 soft starters can be used without restriction in the following network
configurations:
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networks with a grounded or ungrounded star point,
networks with an isolated star point (IT networks),
networks with a grounded phase conductor.
DS7 Soft starter
07/10 MN03901001Z-EN
www.eaton.com
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