Voltage Clamping Module (Vcm); Description - Siemens SINAMICS S120 Equipment Manual

DC link components

10.5 Voltage Clamping Module (VCM)

10.5 Voltage Clamping Module (VCM)
10.5
10.5.1

Description

Under certain unfavorable conditions, voltage rises can occur in extended drive line-ups due
to the stimulation of the system resonance frequency. This can be particularly damaging for
the insulation systems of the connected motors since partial discharges can occur.
The Voltage Clamping Module (VCM) ensures that the motor voltages are limited to
permissible values even when resonance occurs. The Voltage Clamping Module must
always be used if the total lengths of all the motor and DC link cables exceed the following
value:
• 350 m for shielded cables.
• 560 m for unshielded cables.
In conjunction with the VCM, the following total cable lengths are permitted:
• 630 m for shielded cables
• 850 m for unshielded cables
Limitations/secondary conditions
The following secondary conditions must be observed:
• Power derating for Line Module to 80%.
• Max. step-up factor (rectification factor V
• No built-in motors must be connected (torque motors, linear motors).
• Operation on TN networks only.
• The EMC limit values (radio interference voltage) are no longer observed, which means
Compatibility
The VCM can be integrated in the drive line-up with:
• Internal air cooling with mounting brackets (included in the scope of supply)
• External air cooling
• Cold plate cooling
10-24
that special measures may have to be implemented in the system.
On request: Line filter manufactured by, e-mail: emv.labor@epcos.com
/V ) with controlled infeed: 150%.
dc line
Equipment Manual Booksize Cold-Plate Power Sections
Manual, (GH4), Edition 06.2005, 6SL3097-2AJ00-0BP2