Moog G396-026, Руководство по эксплуатации

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Programmable Multi-Axis Servo Drive Power Supply Unit Operation Manual
ID no.: CA97556-001 Date: 03/2015
moog
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Electrical installation
3.2.3 Earthing
All earthed points and components must, as far as possible, be routed by low-resistance,
highly conductive means directly to the central earthing point (e.g. PE rail, main earth).
This creates an earthing system which connects all connection locations in a star
configuration to the earthing point. This central earthing point must be unambiguously
defined. This earthing point can be expanded across the entire backing plate with an
EMC connection.
Pay attention to the following points in relation to earthing:
y Earthed surfaces act as shields and reduced electromagnetic fields in the
surrounding area. Consequently, metallic surfaces should be connected to earth
via low-resistance HF connections. In EMC terms, it is not the cross-section of
the cable which is decisive, but the surface on which high-frequency currents
(caused by the skin effect) can discharge.
y Connect the PE conductors of the components in a star configuration inside the
cabinet.
y Avoid plug-in connections.
y
Also connect the walls and doors of the cabinet to earth.
y Large openings in the cabinet (windows, fans, display) will impede the shielding
effect of the cabinet and must be protected by additional shielding for the HF
area.
y Earth residual wires on at least one side, so as to prevent static.
y
Remove paint and corrosion from contact points and connect them across a
wide area.
y Tin-plated, galvanised, aluminised or cadmium-plated elements should be
preferred to painted components. This will also avoid having to scratch off
varnish layers. Avoid plug-in connections, or use multiple contacts for the shield
connection in the connector. The Power Supply Units have a rear panel made of
aluminised and galvanised sheet steel.
y For more information on the PE conductor cross-section see Table 3.2, p. 33.
3.2.2 Cable laying
Pay attention to the following points when laying cables:
y Lay mains, motor and signal cables isolated from each other. Observe a
minimum clearance of 200 mm (7.87 in).
y
When installing close, use isolating plates mounted directly and conductively on
the backing plate as shielding.
y Lay the conductors tight to the earth potential. When using plastic cable ducts,
they must be mounted directly on the backing plates or the frame. Cables must
not be spanned over free space, otherwise they might act as antennas.
y Avoid unnecessary cable lengths and “spare loops”.
y Lay long cables at locations not susceptible to interference. Otherwise
additional coupling points may be created.
y
Lay motor cables without interruptions (e.g. not via terminals) and by the
shortest route out of the cabinet.
y Twist cables of the same circuit.
y Ideally, lay the signal cables isolated from the encoder cables.
y All signal cables should be grouped together and routed away upwards.
y Avoid extending cables by way of terminals.
y Earth residual wires on at least one side, so as to prevent static.