Siemens SIMOTICS FD 1MM1 Series, Operating And Installation Instructions

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6.5.8 Using single-stranded cables
WARNING
High temperatures from induced eddy currents
With high currents and where several single-stranded cables are used instead of multiple-
stranded cables, high temperatures can result in the cable entry area due to induced eddy
currents. A short-circuit and an explosion may occur. This can result in death, serious injury,
or material damage.
● After commissioning, ensure that the temperature limits of the connected power cables are
not exceeded during operation. This temperature effect can be reduced by altering the
conditions at the entry points or by using modified cable entry plates after consultation with
the manufacturing plant.
● Use a cable entry plate made of non-ferrous metal.
6.5.9 Internal equipotential bonding
Between the ground terminal in the terminal box enclosure and the machine enclosure, the
fixing screws of the terminal box serve as PE conductor connection.
Between terminal box cover and terminal box enclosure, the cover fixing screws serve as
equipotential bonding.
A special external ground conductor is only installed if, for example, flat seals are mounted
without additional support.
When performing any installation work, you must always take care to ensure that all
equipotential bonding measures remain effective.
6.5.10 Stepless mating face for the seal in the terminal box cover
The sealing face of the terminal box cover is formed by the terminal box enclosure and the cable
entry element. Therefore make sure these parts are correctly aligned, so as to ensure the seal
and hence the degree of protection.
Align the cable entry support and the cable entry plate to the terminal box enclosure so that the
sealing surface between the terminal box and the terminal box cover form a flat face. There
must be no steps in the sealing area.
Electrical connection
6.5 Inserting and routing the cables
SIMOTICS FD 1MM1
Operating Instructions 02/2019
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