Parker Hannifin
Appendix C Regulatory Compliance – UL and CE 193
Figure 52 360° Bonding Techniques
All braid termination connections must remain secure. For small
diameter cables, it may be necessary to fold back the braid to increase
the effective diameter of the cable so that R-Clamps are secure.
Within the cabinet itself, all the motor cables should lie in the same
trunking as far as possible. Keep the cables separate from any low-level
control signal cables. This applies particularly where the control cables
are unscreened and run close to the drive.
There must be no break in the 360° coverage that the screen provides
around the cable conductors.
A steel equipment cabinet will screen radiated emissions provided all
panels are bonded to a central earth point. Separate earth circuits are
commonly used within equipment cabinets to minimize the interaction
between independent circuits. A circuit switching large currents and
sharing a common earth return with another low-level signal circuit could
conduct electrical noise into the low level circuit, thereby possibly
interfering with its operation. For this reason, so called ‘dirty earth’ and
‘clean earth’ circuits may be formed within the same cabinet, but all
such circuits will eventually need to be returned to the cabinet’s main
star earth point.
Mount the individual drives and EMC filter on a metal earth plane. The
earth plane will have its own individual star point earth that should be
hard wired (using an insulated copper conductor) back to the cabinet’s
‘clean earth’ connection point.
Panel mounting can provide a similar measure of EMC performance if
strict attention is paid to cable screen termination and cable layout.
Again, the machine builders primary focus should be on ensuring
operators are kept safe from all hazards.
• Install a Mains filter. Aries drives require an EMC mains supply filter
to meet EMC emission requirements. It is recommended that the
drive is mounted on a conductive panel which is shared with the
EMC filters. If the panel has a paint finish, it will be necessary to