Esd Guidelines - Siemens PM250 Hardware Installation Manual

4.8

ESD guidelines

Avoiding Electromagnetic Interference (EMI)
The inverters are designed to operate in an industrial environment where a high level of EMI
can be expected. Most installations do not give problems. However, it is good engineering
practice to conform to the following guidelines - this will reduce the likelyhood of problems
during operation.
Actions to take
● Ensure that all equipment in the cubicle is well grounded using short, thick grounding
● Make sure that any control equipment (such as a PLC) connected to the inverter is
● Connect the return ground from the motors directly to the ground connection (PE) on the
● Flat conductors are preferred as they have lower impedance at higher frequencies.
● Terminate the ends of the cable neatly, ensuring that unscreened wires are as short as
● Separate the control cables from the power cables as much as possible, using separate
● Whenever possible, use screened leads for the connections to the control circuitry.
● Ensure that the contactors in the cubicle are suppressed, either with R-C suppressors for
● Use screened or armored cables for the motor connections and ground the screen at
Screening methods
For all frame sizes the Screen Termination Kit is supplied as an optional extra. It allows easy
and efficient connection of the necessary screening. For further details on the Screen
Termination Kit, please refer to the SINAMICS G120 catalog.
PM250 Power Module
Hardware Installation Manual, 09/2012, A5E01003502B AD
cable connected to a common star point or busbar.
connected to the same ground or star point as the inverter using a short thick link.
associated inverter.
possible.
trunking, if the cables cross they should cross at 90º to each other.
AC contactors or 'flywheel' diodes for DC contactors fitted to the coils. Varistor
suppressors are also effective. This is important when the contactors are controlled from
the inverter relay.
both ends using the cable clamps.
WARNING
Safety regulations must not be compromised when installing inverters!
Siemens Parts
Connecting
4.8 ESD guidelines
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