The American Power Conversion (APC®) Rack Air Distribution Unit (ADU) works with an existing
precision air conditioning system to deliver cool air to equipment contained in a NetShelter
SX
enclosure or other 19-inch EIA-310-D enclosure with a removable floor. The ADU, installed at
the bottom of the enclosure, pulls supply air directly into the enclosure, preventing the conditioned
air from mixing with warm ambient air before it reaches the equipment. Dual fans provide the
increased air flow needed to cool densely-packed equipment and improve air delivery in poor static
pressure areas, solving many of the heat issues facing data centers.
Features
Features of the ADU include:
• Compact size (2 U)
• Dual input connectors for redundant power
®
VX or
• Two fans with independent switches
• Replaceable air filter — 30% efficient by ASHRAE standard 52.1–1992
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Safety Information
Disconnect power to the enclosure before installing the ADU. Failure to do so may result
in personal injury or damage to equipment.
Warning
Check to see that a fan guard is securely in place over each of the air inlet openings.
Do not apply power to the unit until the installation is complete. The ADU contains
moving parts, which are potentially hazardous when operated outside of the enclosure.
Keep fingers and clothing away from the fans. When receiving power, they have moving
parts which can cause personal injury.
Keep the included alcohol swab away from sparks or open flames.
Check that the power cord plugs and sockets are in good condition before installation.
Connect the ADU to a three-wire, 115 Volt outlet. The outlet must be connected to
appropriate branch circuit/mains protection (fuse or circuit breaker). Connection to any
other type of outlet may result in a shock hazard.
Heavy
This equipment contains potentially hazardous voltages. Do not attempt to disassemble
the unit.
Always install and operate the ADU as shown in this manual.
Do not attempt to move a heavily-loaded enclosure by yourself. Doing so introduces risk
of injury due to muscle strain or the tipping of the enclosure. Fully loaded enclosures
require at least two persons to move safely.
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Before You Begin
Inventory
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ItemDescriptionQuantity
Stop bracket1
Left- and right-side guide and rail assembly1 each
Accessories and fasteners:
• Caged nut
• Caged nut installation tool
• Screw—M6 × 12-mm Phillips pan-head
• Alcohol wipes
• Plastic washers
Power cords (NEMA 5-15)2
Bellows 2
Blanking plate1
Duct1
Replaceable air filter (ACF001RF)1
Air intake fan guards2
Fan assembly1
16
1
16
3
16
Receiving inspection
Inspect the package and contents for shipping damage, and make sure that all parts were sent. Report
any damage immediately to the shipping agent. Report missing contents, damage, or other problems
immediately to APC or your APC reseller.
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Overview
Tools required
PencilJigsawCaged nut tool
Installation overview
Cold air exhaust
cooling rack
components
Raised floor
(provided)
7-mm wrench or
nutdriver
Rack
ADU
Hole in
floor
#2 Phillips
screwdriver
Sub floor
SX rack shown
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Cold air intake from
below raised floor
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General Information: Overview
Equipment placement
To avoid interference with air flow, use the uppermost part of the enclosure for any equipment that
extends forward over the air outlet of the ADU.
Deeper
equipment
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Installation
Guides and Rails
To install the guide and rail assemblies:
1. Remove the bottom panel of the enclosure.
2. Locate the position for the guide and rail assembly on each of the four vertical mounting rails of
the enclosure, at the second U-space from the bottom of the rack. (To identify a U-space on a
mounting rail, see the documentation included with your enclosure.)
3. Using the caged nut tool (provided), install caged nuts in the mounting holes 2 U-spaces from
the bottom on the interior of each vertical rail.
4. If necessary, adjust the length of the guide and rail assemblies to fit the depth of your enclosure
by loosening the 7-mm nuts on the outside of each rail.
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5. From the front of the enclosure, attach the front guide and rail flanges to the outside of the
vertical rails using four M6 × 12 Phillips pan-head screws and four plastic washers. Push and
hold each bracket firmly toward the outside of the enclosure when tightening the screws.
6. At the rear of the enclosure, attach the rear guide and rail flanges to the outside of the vertical
rails using two M6 × 12 Phillips pan-head screws and two plastic washers in the top hole of
each guide and rail assembly. Push and hold each bracket firmly toward the outside of the
enclosure when tightening the screws.
7. Mount the stop bracket over the guide and rail assemblies by fastening four M6 × 12 Phillips
pan-head screws and four plastic washers in the bottom holes of each guide and rail.
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Installation: Guides and Rails
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8. After the rails are in position, retighten any 7-mm nuts loosened in step 4.
Mounting rail modifications for shallow vertical rail spacing
This section applies only to shallow rack vertical-rail spacing applications. The
repositioning of the rear mounting bracket is necessary when mounting rails are used in
Note
shallow rack vertical-rail spacing applications.
Shallow rack vertical-rail distance-
16.25 to 19.0 in (412.8 to 482.6 mm)
Perform this procedure for both the left and the right mounting brackets.
Note
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Installation:Guides and Rails
1. Remove and discard the two adjusting
screws that attach the rear mounting
bracket to the mounting rail.
2. Reposition the rear mounting bracket
by sliding it onto the forward tab of
the mounting rail.
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Note
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The rear mounting bracket will slide freely on the forward tab of the mounting rail until
the rail assembly is attached to the enclosure.
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Bellows and Ducts
Installation: Guides and Rails
The bellows seals the area between the fan duct and the floor. To install
the bellows in a NetShelter SX rack, see “NetSheltet SX rack bellows
assembly” on this page. To install the bellows in a NetShelter VX rack,
see “NetShelter VX rack bellows assembly” on page 10.
The kit contains two flexible bellows. For NetShelter SX rack
installations, only one flexible bellows is required.
Note
NetShelter SX rack bellows assembly.
1. Unfold one flexible bellows.
SX rack bellows
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VX rack bellows
2. Fold the top and bottom hook and loop
tape on all four sides of the bellows.
3. Proceed to “Duct assembly” on page 12.
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Hook-and-loop tape on
underside of folds
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Installation:Guides and Rails
NetShelter VX rack bellows assembly.
1. Unfold both flexible bellows as shown.
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2. Orient one bellows so that the hook-and-
loop tape material is on the top outside
edge. Fold down the top edges on all four
sides of the hook-and-loop tape. This is
considered the top section of the bellows.
Top section
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Hook-and-loop tape on
underside of folds
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Installation: Guides and Rails
3. Orient the second bellows so that it has the
hook-and-loop tape material on the bottom
outside edges. Fold all four bottom insides
edges of the hook-and-loop tape. This is
considered the bottom section of the
bellows.
4. Remove the hook portion of the hook-
and-loop tape from all four edges of the
inside (top section). Remove the loop
portion of the hook-and-loop tape from
all four edges of the outside (bottom
section).
Bottom section
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Hook-and-loop tape on
underside of folds
Remove hook tape
Top section
Bottom section
Remove loop tape
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Installation:Guides and Rails
5. Assemble the top and bottom
sections, securing them with the
hook-and-loop tape on all four
sides (as shown).
Duct assembly
1. Place the duct on the guide and rail assemblies with the slotted holes to the rear of the enclosure.
Slide the assembly to the back of the enclosure as far as it will go.
Top section
Bottom section
Loop tape on
top inside
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Hook tape on
bottom outside
2. Locate the holes in the bottom of each rail flange that align with the center of the duct. Using
the caged nut tool, install a caged nut in each of the holes.
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3. Fasten the duct to the rail assemblies using two M6 × 12 Phillips
pan-head screws and the caged nuts installed in the preceding step.
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Cutting an opening in the floor tile
1. Using the inside edge of the duct opening as a template, mark the location for the opening to be
created in the raised floor tile.
2. Move the enclosure to provide access to the floor tile.
3. Remove the floor tile and cut an opening in the tile at the location marked. Use tools that will
provide a clean, accurate cut.
Installation: Guides and Rails
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4. Using the supplied alcohol swab, clean the edges of the opening in the floor tile.
5. Remove the hook portions of the hook-and-loop tape from the bottom lip of the fabric portion of
the duct. Remove the protective plastic that covers the adhesive. Place the tape along the
perimeter of the opening, adhesive-side down.
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6. Reinstall the floor tile in its original position.
7. Move the enclosure to its original position and stabilize it.
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Installation:Guides and Rails
Bellows installation
1. Push the bellows through the duct opening and attach the bellows to the floor using the
hook-and-loop tape.
2. Pull the bellows material up through the duct opening. Remove the loop halves of the
hook-and-loop tape from the top lip of the bellows. Remove the protective plastic covering the
adhesive. Place the tape along the perimeter of the duct opening, adhesive-side down.
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3. Attach the top lip of the bellows material to the duct perimeter using the hook-and-loop tape.
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Fan Assembly
1. Place the filter in the filter housing of the duct so that the arrow on the filter points upward to
match the intended air flow of the Air Distribution Unit.
2. With the front of the fan assembly facing the front of the enclosure, insert the rails on the sides
of the fan assembly into the guides on the guide and rail assemblies.
3. Slide the fan assembly toward the rear of the enclosure until the rails lock into place.
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4. Tighten all the screws holding the guide and rail assemblies to the vertical rails.
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5. Close the front door of the enclosure and, from the rear, push the fan assembly fully forward
until it touches the front door of the enclosure.
6. Using a 7-mm wrench or nutdriver, adjust the stop bracket to prevent the fan assembly from
sliding back toward the rear of the enclosure.
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Installation:Fan Assembly
Blanking plate installation
If the 3 U-space position immediately above the Air Distribution Unit is open, you must
cover it with the blanking plate provided for proper operation and maximum cooling.
Note
1. Using the caged nut tool, install caged nuts on the inside of each vertical rail at the location that
corresponds to mounting holes on the blanking plate.
2. Attach the blanking plate using four M6 × 12 Phillips pan-head screws and four plastic washers.
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Other openings
For proper operation and maximum cooling, cover all other openings in the enclosure with blanking
plates, part number AR8136BLK (not provided).
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Connecting to the power supply
To supply power to the Air Distribution Unit:
1. Using one of the supplied power cords, insert the connector to the “A” input receptacle on the
rear of the unit. Plug the other end into a UPS or other device that provides protected power.
Installation: Fan Assembly
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AC
A B
FAN
1 2
2. To provide redundant power to the unit, use the remaining “B” receptacle to connect the Air
Distribution Unit to a source of protected power.
3. Cords may be bundled and tie-wrapped to provide clearance for other components.
Replacing the perforated floor tile
The perforated floor tile in front of the enclosure containing the Air Distribution Unit can be replaced
with solid floor tiles under these conditione:
• Other equipment in the vicinity is not dependent on the airflow.
• Under-floor pressure is a concern.
Replacing the perforated floor tile can increase air flow in the other areas of the data center.
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Operation and Maintenance
Start-up
Before applying power to the Air Distribution Unit, remove any debris that may be
located in or near the fan rotors. Failure to remove debris can result in damage to
equipment or cause bodily harm.
Warning
Check operation of the unit:
1. Apply power to Fan 1 by pressing the
Do not apply power to the unit with the air intake fan guards removed.
corresponding switch on the rear of the unit,
air should be flowing out of the Air
Distribution Unit
AC
A B
FAN
1 2
2. Turn off Fan 1, and repeat the test for Fan 2.
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When to use only one fan
Depending on the height of the enclosure and the heat output of installed equipment, you may choose
to operate only one fan, reducing energy consumption. Smaller enclosures often require only one
operating fan.
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You may also choose to operate both fans during normal operation, and turn off one fan in the event
of a loss of utility power. This will conserve run-time of the uniterruptible power supply (UPS)
battery.
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Operation and Maintenance: Start-up
Replacing the air filter
Replace the air filter whenever other system air filters are scheduled to be replaced, or at least once a
year.
1. Turn off both fans in the fan assembly, and wait for the fans to stop.
2. Unplug the power cord(s) from the back of the Air Distribution Unit.
3. Open the front of the enclosure and slide the fan assembly forward as far as it will go.
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4. From the rear of the enclosure, remove the old filter, and replace it with a new filter
(ACF001RF).
Note
The air filter might need to be accessed from the front of the enclosure because of
interfering wires and cables. To access the filter from the front, slide out and remove the
fan assembly.
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Warranty and Service
Limited warranty
APC warrants the Rack Air Distribution Unit to be free from defects in materials and workmanship
for a period of two years from the date of purchase. Its obligation under this warranty is limited to
repairing or replacing, at its own sole option, any such defective products. This warranty does not
apply to equipment that has been damaged by accident, negligence, or misapplication or has been
altered or modified in any way. This warranty applies only to the original purchaser.
Warranty limitations
Except as provided herein, APC makes no warranties, expressed or implied, including
warranties of merchantability and fitness for a particular purpose. Some jurisdictions do not
permit limitation or exclusion of implied warranties; therefore, the aforesaid limitation(s) or
exclusion(s) may not apply to the purchaser.
Except as provided above, in no event will APC be liable for direct, indirect, special, incidental,
or consequential damages arising out of the use of this product, even if advised of the possibility
of such damage.
Specifically, APC is not liable for any costs, such as lost profits or revenue, loss of equipment, loss of
use of equipment, loss of software, loss of data, costs of substitutes, claims by third parties, or
otherwise. This warranty gives you specific legal rights and you may also have other rights, which
vary according to jurisdiction.
Obtaining service
To obtain support for problems with your Rack Air Distribution Unit:
0
1. Note the serial number. This is on the back of the Fan Assembly.
2. Contact Customer Support at a phone number at a phone number on the back cover of this
document. A technician will try to help you solve the problem by phone.
3. If you must return the product, the technician will give you a return material authorization
(RMA) number. If the warranty expired, you will be charged for repair or replacement.
4. Pack the unit carefully. The warranty does not cover damage sustained in transit. Enclose a
letter with your name, address, RMA number and daytime phone number; a copy of the sales
receipt; and a check as payment, if applicable.
5. Mark the RMA number clearly on the outside of the shipping carton.
6. Ship by insured, prepaid carrier to the address provided by the Customer Support technician.
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Life-Support Policy
General policy
American Power Conversion (APC) does not recommend the use of any of its products in the
following situations:
• In life-support applications where failure or malfunction of the
expected to cause failure of the life-support device or to affect significantly its safety or
effectiveness.
• In direct patient care.
APC will not knowingly sell its products for use in such applications unless it receives in writing
assurances satisfactory to
customer assumes all such risks, and (c) the liability of American Power Conversion is adequately
protected under the circumstances.
APC that (a) the risks of injury or damage have been minimized, (b) the
APC product can be reasonably
Examples of life-support devices
The term life-support device includes but is not limited to neonatal oxygen analyzers, nerve
stimulators (whether used for anesthesia, pain relief, or other purposes), autotransfusion devices,
blood pumps, defibrillators, arrhythmia detectors and alarms, pacemakers, hemodialysis systems,