Installation 215
14.11 Installation guide for EMC
Special consideration must be given to installations in member states of the European Union regarding noise
suppression and immunity. According to IEC 1800-3 (EN618 00-3) the drive units are classified as Basic Drive
Modules (BDM) only for professional assemblers and for the industrial environment. Although CE Marking is
made against the EMC Directive, application of EN 61800-3 means that no RF emission limits apply. The
drive manufacturer is responsible for the provision of installation guidelines. The resulting EM C behaviour is
the responsibility of the manufacturer of the system or installation. The units are also subject to the LOW
V OLT A GE DIRECTIVE 73/23/EEC and are CE marked accordingly.
Following the procedures outlined will normally be required for the drive system to comply with the European
regulations, some systems may require different measures.
Installers must have a level of technical competence to correctly install. Although the drive unit itself
does not require control of RF emissions, it has been designed and tested to comply with the most stringent
emissions and immunity requirements on all ports.
14.11.1 3-phase pow er supply port
The 3-phase po wer supply port is subject to alternative guidelines, as described belo w. Compliance with
emissions limits on this port may or may not be required depending on the environment. If requi red then
compliance can be achieved by fitting a separate filter unit, contact supplier for details.
EN618 00-3 specifies 2 alternative operating environments. These are the domestic (1
st
environment) and
industrial (2
nd
environment). There are no limits specified for conducted or radiated emissions in the Industrial
environment, hence it is usual for the filter to be omitted in industrial systems.
Definition of an industrial environment: Includes all establishments other than those directly connected
to a lo w voltage pow er supply net w ork which supplies buildings used for domestic purposes.
In order to meet mains conducted emissions limits on this port for the 1
st
environment, a separate filter is
required. Please refer to supplier for a suitable filter to meet the Class A (EN 618 00-3 restricted distribution,
domestic environment).
14.11.2 Earthing and screening guidelines
Important points to note are:
A separate earth conductor is taken from the motor housing and is run adjacent to the drive conductors right
up to the main earth terminal on the drive. This conductor should not be grounded separately to any other
earth point.
The drive earth terminal should be separately taken to the cabinet star earth point or earth busbar, as should
the 0 V connection reference at Terminal 13.
Motor drive and three-phase supply cables should be segregated from other cables in the cabinet, preferably
by a distance of at least 300mm.
Motor drive cables can be screened or armoured, especially if they pass near other sensitive apparatus, and
the screening should be bonded to the motor housing and the point of entry of the cabinet using 360º gland
techniques.
It is understood that the bonding of both ends of the screening and earth conductors may result in significant
earth current flo w if the motors and control cabinet are in widely different locations, so that there are large
earth potential differences. In these circumstances it is recommended that a separate parallel earth conductor
(PEC), which may be a bonded metal conduit, is used alongside the drive cables to give a preferential route
for this current. See IEC 61000-5-2 for more detail. Installation in conformance with this standard is regarded
as good practice and will result in improved EMC of the whole system.
WARNING Safety earthing always takes precedence over EMC earthing.
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