Braking Resistor - Siemens SINAMICS V20 Operating Instructions Manual

Options and spare parts
B.1 Options
B.1.4

Braking resistor

Operating conditions
Make sure that the resistor to be fitted to the SINAMICS V20 is adequately rated to handle
the required level of power dissipation.
All applicable installation, usage and safety regulations regarding high voltage installations
must be complied with.
If the converter is already in use, disconnect the prime power and wait at least five minutes
for the capacitors to discharge before commencing installation.
This equipment must be earthed.
Hot surface
Braking resistors get hot during operation. Do not touch the braking resistor during
operation.
Using an incorrect braking resistor can cause severe damage to the associated converter
and may result in fire.
A thermal cut-out circuit (see diagram below) must be incorporated to protect the
equipment from overheating.
NOTICE
Device damage caused by improper minimum resistance values
A braking resistor with a resistance lower than the following minimum resistance values can
damage the attached converter or braking module:
• 400 V converter frame sizes A to C: 56 Ω
• 400 V converter frame size D/E: 27 Ω
• 230 V converter frame sizes AA to C: 37 Ω
Functionality
An external braking resistor can be used to "dump" the regenerative energy produced by the
motor, thus giving greatly improved braking and deceleration capabilities.
A braking resistor which is required for dynamic braking can be used with all frame sizes of
converters. Frame size D and E are designed with an internal braking module, allowing you
to connect the braking resistor directly to the converter; however, for frame sizes AA to C, an
additional dynamic braking module is required for connecting the braking resistor to the
converter.
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WARNING
WARNING
SINAMICS V20 Converter
Operating Instructions, 10/2019, A5E34559884-012