Moeller ps4-201-mm1, Hardware And Engineering

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Engineering
28
04/
99 AW
B
27-
1184 G
B
Avoiding interference Cabling and wiring
Cables come under the following categories:
Power cables (e.g. cables carrying heavy current
or cables to power converters, contactors or
solenoid valves)
Control and signal cables
(e.g. digital input cables)
Measuring and signal cables (e.g. field bus
cables)
In order to keep interference to a minimum ensure
that the cabling both inside and outside the control
cabinet is laid correctly as follows:
왘
Avoid long, parallel cable runs with adjacent
cables of different power ratings.
왘
Always lay AC cables separately from DC cables.
Observe the following minimum clearances:
At least 10 cm (4
″
) between power cables and
signal cables.
At least 30 cm (12
″
) between power cables and
data/analog cables.
왘
Make sure that the supply and return cables
belonging to each circuit are laid together. The
opposing direction of current flow means that the
sum of all the currents is zero so that any fields
which are produced are compensated.
Power, control and signal cables must always be
laid as far apart from one another as possible, in
order to prevent capacitive and inductive
interference. If separate cabling is not possible,
the cables that represent the potential source of
interference must be screened above all.