Siemens SINAMICS G130 Engineering Manual page 437

Note:
The Braking Units installed in the Central Braking Modules can produce a higher peak braking power than the
standard braking resistors. For this reason, the braking power P
braking power specified in the table above for the relevant combination of Central Braking Module and braking
resistor. The 15-second peak power P
of the Central Braking Modules. Please note, however, that the permissible load duty cycle duration for the braking
resistors is longer (20 minutes) than the permissible load duty cycle duration of the Central Braking Module.
The standard braking resistors are only dimensioned for occasional regenerative operation. If the braking resistor is
not sufficient to meet the demands of special applications, a suitable braking resistor design must be requested for
the specific project.
Load duty cycle of standard braking resistors
For the evaluation of the thermal contact on the braking resistor in the CU320-2 or in a higher-level controller, this
contact must be wired in the customer's plant in addition to the power connection to the Central Braking Module. In
order to provide reliable thermal protection of the braking resistor, the following must be taken into consideration:
§ The braking power of the resistor must not be exceeded.
§ When the temperature switch responds, the following must be ensured:
- The drives producing regenerative energy must be stopped, the temperature switch must be
integrated into the inverter monitoring circuit "External fault".
- Control measures to prevent a restart of the drive until the braking resistor has cooled down.
A cable length of up to 100 m is permitted between the Central Braking Module and braking resistor. The cables must
be routed in such a way that they are short-circuit and ground-fault proof.
The braking resistor must be installed as a free-standing component. Objects must not be deposited on or above the
braking resistor. Ventilation space of 200 mm is required on each side of the braking resistor. Sufficent space must
be maintained between the braking resistor and flammable objects. It has also to be ensured that the place of
installation is able to dissipate the heat produced by the braking resistor. The installation should not be carried out
near fire detectors as they could respone by the produced heat. When outdoor installation of the braking resistor is
required protection against water must be ensured as the degree of protection of IP21 is not sufficient in this case.
SINAMICS S120 Cabinet Modules
BR
of the braking resistors corresponds to the 150-second braking power P
BR
SINAMICS Engineering Manual – November 2015
Engineering Information
of the braking resistors limits the permissible peak
Ó Siemens AG
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