Johnson Controls DVN 5000 Series, Manual, Page: 13 / 46

Environmental Guidelines DVN 5000
24-10520-22 Rev. – 11
This document contains confidential and proprietary information of Johnson Controls, Inc.
© 2009 Johnson Controls, Inc.
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Use fans if you choose a vented front door with less than 68% open area,
except when the equipment has high static pressure front-intake fans built in
(which is rare). The DVN 5000 has front-intake fans, but they are not high
static pressure fans.
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Use a blower rather than a fan in situations with inlet restrictions.
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Use inlet air filters in environments with a high level of airborne particles or
dust to extend the service life of the equipment.
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Install gasketed and sealed NEMA®-rated racks in harsh environments where
filters quickly become clogged. For more information on NEMA ratings and
standards, visit the following sites:
http://www.cdynamics.com/nema-4.html
http://www.nema.org/stds/250.cfm
Avoid
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Installing the DVN 5000 rack inside an enclosed area with little or no
ventilation.
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Allowing the temperature in the room to exceed recommended temperature
levels. A room that is too hot results in DVN drive failures. A room that is too
cold can generate condensation, damaging the DVN’s internal components.
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Locating the racks directly under supply ductwork.
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Using more than one DVN/DVR in a rack in a passive convection
application.
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Selecting an enclosure with venting built-in to the top face when top-mount
fans are required.
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Downward airflows (fans blowing down), since they create mixed convection
(a mixture of forced air and convection).
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The common belief that an equipment fan working in conjunction with a rack
fan will increase the airflow. It provides greater static pressure, but does not
increase the airflow.
Thermal System
This thermal system consists of two types of airflow: how the heat travels through
the rack and how the air moves throughout the room. The interactions between these
two airflows are important and must be considered when taking a systems approach.
All heat (BTU/Hr.) generated by equipment must first be removed from the rack,
and then the room itself must have the ability to remove the total heat from all racks.
Many installations do not have the luxury of an air-conditioned environment.
Consider how the room itself will vent.