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APEX615n Installation Guide
General Considerations Applicable to all Products
External enclosures
The measures described in these recommendations are primarily for the purpose of controlling
conducted emissions. To control radiated emissions, all drive and control systems must be
installed in a steel equipment cabinet which will give adequate screening against radiated
emissions. This external enclosure is also required for safety reasons. There must be no user
access while the equipment is operating. This is usually achieved by fitting an isolator switch
to the door assembly.
Packaged products must be mounted to a conductive panel. If this has a paint finish, it will be
necessary to remove the paint in certain areas where specified.
To achieve adequate screening of radiated emissions, all panels of the enclosure must be bonded
to a central earth point. The enclosure may also contain other equipment and the EMC
requirements of these must be considered during installation. Always ensure that drives and
controllers are mounted in such a way that there is adequate ventilation.
AC supply filtering
These recommendations are based on the use of proprietary screen filter units which are readily
available. However the full EMC test includes a simulated lightning strike which will damage
the filter unless adequate surge suppression devices are fitted. These are not normally
incorporated into commercial filters since the lightning strike test can be destructive. This test
is normally carried out on the overall system and not on individual components, therefore the
surge protection should be provided at the system boundary.
Try to arrange the layout of drive and filter so that the AC input cable is kept away from the
filter output leads. It is preferable for the current path to be as linear as possible without
doubling back on itself - this can negate the effect of the filter. Mount the filter within 2
inches (50mm) of the drive or transformer, if required, and run the input cable and any earth
cables close to the panel.
The next section of this Appendix lists the recommended AC Input Power Filter for the
APEX615n.
Control signal connections
High-quality braided-screen cable should be used for control connections. In the case of
differential inputs, it is preferable to use cable with twisted pairs to minimize magnetic
coupling. This applies to both analog and digital signals. Control cables leaving the enclosure
should have the cable screen returned to a local ground point near the product. Where screened
leads are used in control circuits that are only opto-isolated at one end, the screen must be
referenced to earth at the non-isolated end. Where there is isolation at both ends of the
connection, earth the screen at the receiving end. This is to give protection against coupled
noise impulses and fast transient bursts.
Remember to route control signal connections well away (at least 8 inches) from relays and
contactors. Control wiring should not be laid parallel to power or motor cables and should
only cross the path of these cables at right angles. Bear in mind that control cables connected
to other equipment within the enclosure may interfere with the controller or drive, particularly
if they have come from outside the cabinet. Take particular care when connecting external
equipment with the cabinet door open, for instance a computer or terminal; static discharge
may cause damage to unprotected inputs.
Motor Cabling
In order to prevent electrical cross-talk, motor cables not incorporating a braided screen shield
must remain within earthed metal conduit the entire exposed length of travel. It is advised that
each high power motor cable utilize its own conduit.
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