Rockwell Automation 7000A PowerFlex Medium Voltage AC Drive - Air-Cooled (A Frame) - Manual (Page 45)

Drive Installation 2-15
7000 “A” Frame 7000A-RM001A-EN-P – January 2011
External Ducting The PowerFlex 7000’s design allows for its exhaust air to be ducted
outside of the control room. In this case, consideration must be given
to the conditions present in the atmosphere outside the control room.
When externally ducting the exhaust air and bringing in cleansed
outside air, the following requirements must be met:
A T T E N T I O N A T T E N T I O N If the drive configuration has more than one
exhaust outlet, ensure that each outlet is
ducted separately to prevent back-feeding of
hot exhaust into the drive.
External ducting including an external filtering system must not
add more than 50 Pa (0.2 inches of water) pressure drop to the
PowerFlex 7000 drive air flow system.
The control room must provide slightly more make-up air
creating a pressurized room. This slight pressurization ensures
no unfiltered air is drawn into the room.
The drive is intended to operate in conditions with no special
precautions to minimize the presence of sand or dust, but not in
close proximity to sand or dust sources. This is defined by IEC
7211 as being less than 0.2 mg/m
3
of dust. If outside air does not
meet this condition, the air must be filtered to ASHRAE
(American Association of Heating, Refrigeration and Air-
Conditioning Engineers) Standard 52.2 MERV 11 (Minimum
Efficiency Reporting Value). This filtration eliminates from 65%
to 80% of the particulate in Range 2 (1.0 – 3.0 µm) and 85% of
the particulate in Range 3 (3.0 – 10.0 µm). This filter system
must be cleaned or changed regularly to ensure proper flow.
The make-up air must be between 0 – 40 degrees C.
Relative humidity must be less than 95% non-condensing.
Approximately ten percent of drive losses will still be rejected
into the control room and must be addressed to maintain the
temperature in the control room within specification.
Failure to maintain proper flow of cooling air into the control
room can result in the drive stopping on low differential pressure
across the heatsinks.