Protective Connection And Equipotential Bonding - Siemens S120 Manual

Cabinet design and EMC for components, Blocksize format

10.7 Protective connection and equipotential bonding

10.7 Protective connection and equipotential bonding
Protective connections
The SINAMICS S drive system is designed for use in cabinets with a protective conductor
connection.
The protective conductor connection of the SINAMICS components must be connected to
the protective conductor connection of the control cabinet as follows:
Table 10- 17 Conductor cross-section for copper protective connections
Line supply cable in mm
Up to 16 mm
From 16 ... 35 mm
From 35 mm
For materials other than copper, the cross-section should be increased so that as a
minimum, the same conductivity is attained.
All system components and machine parts must be incorporated in the protection concept.
The protective connection (PE connection) of the motors used must be established through
the motor cable. For EMC reasons, the shield of the motor cable should be connected
through a large surface area both at the Power Module as well as at the motor.
The drive line-up must be arranged on a common bright mounting plate in order to comply
with the EMC limit values. The mounting plate must be connected to the protective conductor
connection of the control cabinet through a low impedance.
Copper cables with appropriate cross-sections (>2.5 mm²) must be used for the protective
connections of the PROFIBUS nodes.
For more information about grounding PROFIBUS, see:
http://www.profibus.com/fileadmin/media/wbt/WBT_Assembly_V10_Dec06/index.html
Functional equipotential bonding
A mounting plate, which is connected with the protective conductor connection of the control
cabinet through a low impedance connection, simultaneously serves as the functional
equipotential bonding surface. This means that no additional functional equipotential bonding
is required within the drive line-up.
If a common bright mounting plate is not available, then equally good functional equipotential
bonding must be established using cable cross-sections as listed in the table above or, as a
minimum, with the same conductivity.
When installing components on standard mounting rails, the data listed in the table also
apply to the functional equipotential bonding. If only smaller connection cross-sections are
permissible at the components, then the largest possible cross-section should be used, e.g.
6 mm
the control cabinet.
438
2
2
2)
2
for SMC. These requirements also apply to distributed components located outside
2
Copper protective connection in mm
The same as the line supply cable
16 mm
2
0.5 x line supply cable
Manual, (GH6), 04/2014, 6SL3097-4AL00-0BP4
2
AC Drive