Emc - Emerson SKA1100025 Getting Started Manual

4.2.1 Use of earth (ground) leakage circuit breakers (ELCB) / residual current
device (RCD)
There are three common types of ELCB/RCD:
Type AC - detects AC fault currents
Type A - detects AC and pulsating DC fault currents (provided the DC current
Type B - detects AC, pulsating DC and smooth DC fault currents
• Type AC should never be used with drives
• Type A can only be used with single phase drives
• Type B must be used with three phase drives
4.3

EMC

4.3.1 Internal EMC filter
It is recommended that the internal EMC filter is kept in place unless there is a specific
reason for removing it.
If the drive is to be used on an IT supply, then the filter must be removed.
The internal EMC filter reduces radio-frequency emissions into the mains supply. Where
the motor cable is short, it permits the requirements of EN 61800-3:2004 to be met for
the second environment.
For longer motor cables, the filter continues to provide a useful reduction in emission
level, and when used with any length of shielded cable up to the limit for the drive, it is
unlikely that nearby industrial equipment will be disturbed. It is recommended that the
filter be used in all applications unless the ground leakage current is unacceptable or
the above conditions are true.
When the internal EMC filter is used on the Commander SK size D, the motor cables (U,
V and W) need to be fed twice through a ferrite ring (provided with the drive), so that the
drive meets the requirements of operating in the second environment.
4.3.2 Removing the internal EMC filter
Figure 4-3 Removal and re-fitting of internal EMC filter
Commander SK Getting Started Guide
Issue Number: 9
reaches zero at least once every half cycle)
A
B
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Internal
EMC filter
Tab fully inserted:
EMC filter fitted
Internal
EMC filter
Tab fully extended:
EMC filter disconnected
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