Moeller XION-PLC-CANopen, Оборудование, инженерия и описание функций

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02/05 AWB2724-1566GB
15
3 Engineering
Control panel layout
The layout of the components inside the control panel is a major
factor for achieving interference-free functioning of the plant or
machinery. During the project planning and design phase, as well
as its implementation, care must be taken that the power and
control sections are kept physically separated from each other. The
power section includes:
• Contactors
• Coupling/interfacing components
• Transformers
• Frequency inverters
• Converters
To effectively exclude any electromagnetic contamination, it is a
good idea to divide the system into sections, according to their
power and interference levels. In small control panels it is often
enough to provided a sheet steel dividing wall, to reduce
interference factors.
Ventilation
A clear space of at least 50 mm must be kept between passive
components, to ensure adequate ventilation. If the neighbouring
components are active elements, such as power supplies or
transformers, then the minimum spacing should be 75 mm. The
values given in the technical specifications must be observed.
Layout of units
Mount the PLC horizontally in a control panel:
Preventing interference
Cable routing and wiring
Cables are divided into the following categories:
• Power cables (e.g. cables that carry high currents, or cables to
converters, contactors or solenoids)
• Control and signal cables (e.g. for digital inputs)
• Measurement and signal cables (e.g. for fieldbus connections)
Take care to implement proper cable routing both inside and
outside the control panel, to keep interference as low as possible:
X
Avoid parallel routing of cable sections in different power
categories.
X
Always keep AC cables and DC separated.
X
Keep to the following minimum spacing:
– at least 10 cm between power cables and signal cables;
– at least 30 cm between power cables and data or analog
cables.
– When routing cables, make sure that the outgoing and return
leads of a circuit pair are routed together: The opposing
currents – and therefore the generated electromagnetic
fields – cancel each other out.
Suppressor circuitry for interference sources
X
Connect all suppressor circuits as close to the source of
interference (contactors, relays, solenoids) as possible.
Shielding
X
Use shielded cables for the connections to the data interfaces.
The general rule is: the lower the coupling impedance, the
better the shielding effect.
Figure 13: Control panel layout
a Spacing > 50 mm
b
Spacing > 75 mm to active elements
c Cable duct
c
b a
b a
b
a
b
a
h Always route power cables and control cables as far apart
as possible This avoid capacitive and inductive coupling.
If the cables cannot be routed separately, shield the cable
causing interference.
h Switched inductors should always have suppressor
circuitry fitted.