SIEMENS
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Siemens NC 62 · 2016
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SINAMICS S120 drive system
Chassis format – DC link components
Braking Modules
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Overview
A Braking Module and the matching external braking resistor are
required to bring drives to a controlled standstill in the event of a
power failure (e.g. emergency retraction or EMERGENCY STOP)
or limit the DC link voltage for brief periods of generator operation,
e.g. when the regenerative feedback capability of the Line Module
is deactivated. The Braking Module includes the power electron-
ics and the associated control circuit. During operation, the DC
link power is converted into heat loss in an external braking resis-
tor. Braking Modules function autonomously. Parallel operation of
several braking modules is possible. In this case, each Braking
Module must have its own braking resistor.
Braking Modules are designed to be built into Motor Modules,
Line Modules or Power Modules in chassis format and are
cooled by the fans on these modules. The supply voltage for the
electronics is taken from the DC link. The Braking Modules are
connected to the DC link by means of the busbar sets included
in the scope of supply or flexible cables and, in the case of the
Basic Line Module of frame size GB, by means of a separate
molded cable set
(see Accessories)
.
The activation threshold of the Braking Module can be adjusted
by means of a DIP switch. The braking power values specified
in the technical specifications apply to the upper activation
threshold.
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Design
The Braking Modules in chassis format feature the following
connections and interfaces as standard:
•
1 DC link connection
•
1 braking resistor connection
•
1 digital input (block Braking Module/acknowledge error)
•
1 digital output (Braking Module inhibited)
•
1 DIP switch for adjusting the activation threshold
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Integration
Braking Modules in chassis format are designed for mounting
in air-cooled units in chassis format. The fan of the Line Module,
Motor Module or Power Module in which the Braking Module
is mounted also cools the Braking Module. Braking Modules
cannot operate autonomously because they are not equipped
with cooling fans.
© Siemens AG 2016