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Unidrive M Modular Installation Guide
Issue Number: 2
5.2.6 Electromagnetic compatibility
Variable speed drives are powerful electronic circuits which can cause
electromagnetic interference if not installed correctly with careful
attention to the layout of the wiring.
Some simple routine precautions can prevent disturbance to typical
industrial control equipment.
If it is necessary to meet strict emission limits, or if it is known that
electromagnetically sensitive equipment is located nearby, then full
precautions must be observed. In-built into the drive, is an internal EMC
filter, which reduces emissions under certain conditions. If these
conditions are exceeded, then the use of an external EMC filter may be
required at the drive inputs, which must be located very close to the
drives. Space must be made available for the filters and allowance made
for carefully segregated wiring. Both levels of precautions are covered in
section 6.13
M70X Position feedback connections on page 83
.
5.2.7 Hazardous areas
The drive must not be located in a classified hazardous area unless it is
installed in an approved enclosure and the installation is certified.
5.3 Terminal cover removal
5.3.1 Removing the terminal covers
Unidrive M size 9/10 D and E are installed with three terminal covers:
Control, input and output terminal covers.
Unidrive M Rectifier is installed with two terminal covers: Input and
output terminal covers. The terminal covers and housing must be
removed to gain access to all the terminals.
Isolation device
The AC supply must be disconnected from the drive using an
approved isolation device before any cover is removed from
the drive or before any servicing work is performed.
Stored charge
The drive contains capacitors that remain charged to a
potentially lethal voltage after the AC supply has been
disconnected. If the drive has been energized, the AC
supply must be isolated at least ten minutes before work
may continue.
Normally, the capacitors are discharged by an internal
resistor. Under certain, unusual fault conditions, it is possible
that the capacitors may fail to discharge, or be prevented
from being discharged by a voltage applied to the output
terminals. If the drive has failed in a manner that causes the
display to go blank immediately, it is possible the capacitors
will not be discharged. In this case, consult Control
Techniques or their authorized distributor.
WARNING
WARNING
Summary of Contents for 09201760D
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