Laying The Signal Lines; Laying The Cable Shields - Siemens SINAMICS GL150 Operating And Installation Instructions

Electrical connection

6.6 Laying the signal lines

Where possible, also connect the cabinet conductively over a large area with the building
ground.
Note
The equipotential bonding conductor does not have the function of a protective conductor. The
equipotential-bonding conductor is required for safe operation and as an interference
suppression measure.
6.6 Laying the signal lines
NOTICE
Malfunction due to common cable installation
Malfunctions can occur in the converter if cables with differing voltage levels are laid together
with internal cables in one cable duct in the cabinet.
Do not run cables coming from the outside, for example to the terminal strips, together with
internal cables in one cable duct.
All signal lines must be shielded. The cable shield should be braided, because cables shielded
by tape or foil are five times less efficiently protected against interference. Always ground the
cable shields at both ends. Contacting at one end is advantageous in exceptional cases only.
Clamp the shield of incoming analog and binary cables to the shield busbar at the entry point
into the cabinet. Continue running the cable, still shielded, to the terminal strip or board. No
shields are connected to the terminal strips or boards.
Serial connecting cables must be shielded. Place the shield on the metallic connector housing.
Also connect the shield to the shield rail. Do not connect the cable shield to a ground pin of
the connector.
The connector housing and front plate of the boards do not provide adequate cable shielding.
Connect the cable shields at both ends to the shield rails in the cabinets. Always use shielded
analog signal cables, regardless of whether they are installed inside or outside cabinets. In
order to increase the effectiveness of the shielding, ground spare conductors at both ends.
6.7

Laying the cable shields

In the case of analog signal lines carrying small signals (mV or µA), attach the cable shield to
the shield bus in the cabinet at one end. In this way you avoid ground loops and line-frequency
interference. You can also connect the open shield end to the enclosure via a radio interference
suppression capacitor (e.g. 0.1 µF 100 V MKT).
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SINAMICS GL150 6SL38503UM114PA0Z
Operating Instructions 04/2017