It (Ungrounded) Systems; Setting The Earth Fault (Ground Fault) Trip Level; Grounded Systems - ABB ACS800-07-0610-3 Hardware Manual

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• Note: Moisture inside the motor casing will reduce the insulation resistance. If this
is suspected, dry the motor and repeat the measuring.
ohm

IT (ungrounded) systems

EMC filter +E202 is not suitable for use in an IT (ungrounded) system. If the drive is
equipped with EMC filter +E202, disconnect the filter before connecting the drive to
the supply network. For detailed instructions on how to do this, please contact your
local ABB representative.
WARNING! If a drive with EMC filter +E202 is installed on an IT system [an
ungrounded power system or a high resistance-grounded (over 30 ohms) power
system], the system will be connected to earth potential through the EMC filter
capacitors of the drive. This may cause danger or damage the unit.

Setting the earth fault (ground fault) trip level

Grounded systems

See page 28.
IT (ungrounded) systems
On ungrounded systems, an external monitoring unit (Bender IRDH265 or IRDH275,
option +Q954) is used. Refer to its documentation for set-up instructions.
Note: On ungrounded systems, the internal earth current monitoring must be
deactivated. See page 28.
Electrical installation
Phone: 800.894.0412 - Fax: 888.723.4773 - Web: www.clrwtr.com - Email: info@clrwtr.com
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