UNIPOWER’s PDUAC3U Series AC power distribution units accept a 3-phase input and
provide single phase outputs that are distributed from the phases to ensure load babance on
the source. They provide AC distribution and overload protection for up to 12 load circuits
distributed through eld wireable terminal blocks.
There are 3 basic congurations operating from nominal 120VAC, 208VAC or 230VAC
outputs respectively. Each of these is available with either 4, 8 or 12 2-pole load circuit
breakers rated at 25A.
Model with and without input surge protection are available.
PDUAC3U SERIES
OPERATING MANUAL
OPERATING MANUAL
These panels are only 3RU high and are supplied with brackets that allow mounting in a
19” frame.
.
Figure 1. PDUAC3U AC Power Distribution Unit
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POWERING TECHNOLOGY
2.0 FEATURES & OPTIONS
The following is a summary of the important features of the PDUAC3U Series.
The following table lists the 18 available standard congurations of the PDUAC3U series.
MODEL NUMBER
PDUAC3U-120-04
PDUAC3U-120-088 x 25A
PDUAC3U-120-1212 x 25A
PDUAC3U-208-04
PDUAC3U-208-088 x 25A
PDUAC3U-208-1212 x 25A
PDUAC3U-230-04
PDUAC3U-230-088 x 25A
PDUAC3U-230-1212 x 25A
PDUAC3U-120-04-SP
PDUAC3U-120-08-SP8 x 25A
PDUAC3U-120-12-SP12 x 25A
PDUAC3U-208-04-SP
PDUAC3U-208-08-SP8 x 25A
PDUAC3U-208-12-SP12 x 25A
PDUAC3U-230-04-SP
PDUAC3U-230-08-SP8 x 25A
PDUAC3U-230-12-SP12 x 25A
Notes:
1. Alternative ratings are available, consult factory.
SURGE
PROTECTION
NO
YES
NOMINAL
AC INPUT
120/208VAC
3-phase
4 wire + GND
120/208VAC
3-phase
4 wire + GND
230/400VAC
3-phase
4 wire + GND
120/208VAC
3-phase
4 wire + GND
120/208VAC
3-phase
4 wire + GND
230/400VAC
3-phase
4 wire + GND
NOMINAL
OUTPUT
120VAC
Line-Neutral
208VAC
Line-Line
230VAC
Line-Neutral
120VAC
Line-Neutral
208VAC
Line-Line
230VAC
Line-Neutral
AC
OUTPUTS
4 x 25A
4 x 25A
4 x 25A
4 x 25A
4 x 25A
4 x 25A
1
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POWERING TECHNOLOGY
4.0 SAFETY & INDUSTRY STANDARDS
4.1 PDUAC3U Series power distribution panels meet the following safety
4.2PDUAC3U Series power distribution units (PDU) are CE marked to indicate
conformance to the European Union’s Low Voltage Directive.
4.3These PDUs operate at voltages that could potentially be hazardous.
Furthermore, inadvertent short circuiting by mis-connection or other error
could be harmful. This product should be handled, tested and installed only
by qualied technical persons who are trained in the use of power systems
and are well aware of the hazards involved.
PDUAC3U SERIES
OPERATING MANUAL
4.4All connections to the PDU should be carefully checked for errors before
applying power to them.
4.5The internal voltages may be at hazardous potentials. The top cover should
not be removed. There are no user-serviceable components in these units.
Removing the top cover will void the warranty.
5.0WARRANTY(summary)
PDUAC3U Series PDUs are warranted for two (2) years from date of shipment against defects
in material and workmanship. This warranty does not extend to products which have been
opened, altered or repaired by persons other than persons authorized by the manufacturer or
to products which become defective due to acts of God, negligence or the failure of customer
to fully follow instructions with respect to installation, application or maintenance.
For a complete text of UNIPOWER’ s warranty conditions please request a copy from your
local Sales Oce.
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POWERING TECHNOLOGY
CB12
CB11
CB10
CB9
CB8
CB7
CB6
CB5
CB4
CB3
CB2
CB1
CB1
CB12
CB11
CB10
CB9
CB8
CB7
CB6
CB5
CB4
CB3
CB2
CB1
CB1
6.0 DESCRIPTION OF OPERATION
6.1 Power Distribution Circuits. Simplified schematic diagrams of the
distribution panels is shown in Figure 2. The inputs from each phase and
Neutral connect to a internal copper bus bars from which the circuit breakers
distribute power to the loads, either one phase and neutral for each circuit
(gure 2a) or two phases for each circuit (gure 2b) where neutral is not
distributed. This latter provides a 208VAC output.
PDUAC3U SERIES
OPERATING MANUAL
25A
CB12
25A
CB11
25A
CB10
25A
CB9
25A
CB8
25A
CB7
25A
CB6
25A
CB5
25A
CB4
25A
CB3
25A
CB2
25A
GND
L3
L2
L1
N
N
L1
L1
L2
(Option SP)
L3
PE
N
L2
L3
Figure 2a. Block Diagram - 4-wire 3-phase to single phase L-N
L3
L2
L1
N
GND
L1
L2
(Option - SP)
L3
PE
N
Figure 2b. Block Diagram - 3-wire 3-phase to two phase L-L (208V)
N
L1
L2
L3
25A
CB12
25A
CB11
25A
CB10
25A
CB9
25A
CB8
25A
CB7
25A
CB6
25A
CB5
25A
CB4
25A
CB3
25A
CB2
25A
N
N
L2 L3
N
L1
N
L3
N
N
L1 L2
N
L3
N
L2
N
L1
N
L3
N
L2
N
L1
L3
L1
L3 L2
L2
L1
L3
L2
L1
L2
L1 L3
L3
L2
L1
L3
L2
L1
L3
L2
L1
L3
L2
L1
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POWERING TECHNOLOGY
(OPTION)
7.0 SPECIFICATIONS
The following specications are typical at 25°C unless otherwise noted.
PDUAC3U SERIES
OPERATING MANUAL
INPUT/OUTPUT
Input Voltage............................3-phase, 120/208 or 230/400VAC
4 wire & GND
Input Current...............................................100A Max. per phase
Load Circuit Breakers
-04 ...............................................................................4 x 25A
-08 ...............................................................................8 x 25A
-12 .............................................................................12 x 25A
The front panel of the PDUAC3U, shown in Figure 3 below, consists of two sections.
The left section contains the output circuit breakers; there are 4, 8 or 12 tted
depending on the exact model. They are each rated at 25A as standard. The right
section accommodates an optional surge protection feature. When this option is
not tted blanking panels are installed.
ENVIRONMENTAL
Operating Temp. Range .........................................-20°C to 50°C
Storage Temp. Range ...........................................-40°C to +85°C
Humidity..........................................0% to 90%, Non-Condensing
PHYSICAL SPECIFICATIONS
Case Material/Finish ............................ Steel/Black Powder Coat
Dimensions, Inches (mm) .........................5.1h x 16.75w x 11.5d
(43.2 x 425.5 x 292.1)
Rack Mounting................................................19” or 23”, 3U High
9.1 Back View. Figure 4 shows the back of of the PDUAC3U. Inputs are at the left
hand end. The outputs are to the right of this and consist of three barrier strips with
associated ground screws. There are sucient connections for connecting to a total
of 3 rectier shelves, each with 4 separate AC inputs.
PDUAC3U SERIES
OPERATING MANUAL
AC INPUT
LOAD CONNECTIONS
LOAD CONNECTIONS
Figure 4. Back Panel View
9.2 Input Connections. The AC power inputs to the PDU are made through the ve
compression terminal blocks marked GND, N, L1, L2 & L3. The recommended
cable size for these connections is #2AWG.
9.3 Output Connections. Output connections are shown in Figure 4. There are 3 sets
of barrier strip terminals. The connections are numbered to correspond with the
numbers of the front panel breakers. Each barrier strip is intended for making output
connections to a single rectier shelf. Above the barrier strips are separate screws
which are used to make the ground connections.
Barrier strip connection use No. 6-32 screws. Recommended wire size is #10AWG.
Figure 5 below shows detailed spacing of the terminals.
(9.53)
0.65
(16.5)
Manual No. pduac3u-3
0.32
Figure 5. Output Barrier Strip Detail
The ground connections use No. 8-32 screws. The recommended wire size for these
connections is #10AWG. Note that it is important to use separate wires for each
ground connection to the rectier shelf.
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POWERING TECHNOLOGY
10.0 UNP ACKING AND INSPECTION
10.1 This PDUAC3U Series PDU was carefully tested, inspected and packaged for
shipment from our factory . Upon receipt of the unit it should be carefully unpacked
and inspected for any damage in shipment.
10.2If there is evidence of damage, do not attempt to test the unit. The freight carrier
should be notied immediately and a claim for the cost of the rectier system should
be led with the carrier for direct reimbursement. Be sure to include the model and
serial number of the damaged unit in all correspondence with the freight carrier.
Also save the shipping carton and packing material as evidence of damage for the
freight carrier’s inspection.
10.3
UNIPOWER will cooperate fully in case of any shipping damage investigation.
10.4Always save the packing materials for later use in shipping the unit. Never ship the
unit without proper packing.
PDUAC3U SERIES
OPERATING MANUAL
11.0 INSTALLATION
11.1 Mounting. This PDU can be mounted in 19-inch racks by using the supplied
brackets. Mount it from the front of the rack using the correct osets to align with
existing rack-mounted equipment.
11.2 Input Connections. Input connections should be made with stripped end wire of
size #2AWG. See Section 9.2.
Connections should be made according to the source voltage as follows:
120VAC Line-Neutral
Connect each phase to L1, L2 & L3 respectively. Connect neutral to N.
208VAC Line-Line
Connect each phase to L1, L2 & L3 respectively. Connect neutral to N.
230VAC Line-Neutral
Connect each phase to L1, L2 & L3 respectively. Connect neutral to N.
11.3 Output connections are made to barrier strip connectors and grounding screws. See
Section 9.3 and Figure 5.
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POWERING TECHNOLOGY
PDUAC3U SERIES
OPERATING MANUAL
Each output provides a single phase voltage of 120VAC, 208VAC or 230VAC
depending on the model. Models with 4 output breakers tted use CB1-4, those
with 8 breakers use CB1-8 and those with 12 breakers use CB1-12.
The internal wiring of the PDU ensures that the phases are distributed as evenly
across the outputs as possible. Make ALL connections to each rectier shelf from
a single barrier strip even if the system does not initially have a full compliment
of rectiers. This will ensure proper load balancing across the input phases and
also allow rectiers to be added at a later date without the need to install additional
cables.
11.4 Checking Connections. Carefully check the input connections to the PDU and
output connections to the load before operating the panel. In particular pay attention
to the input wiring as described in section 11.2. Incorrect connections will not harm
the PDU but may cause serious harm to the load. Check to make sure that the safety
ground connections is made. Make sure that all connections are clean and secure
to minimize contact resistance.
11.5 UL Requir ements. The following should be adhered to when installing this PDU:
Elevated Operating Ambient - If installed in a closed or multi-unit rack assembly,
the operating ambient temperature of the rack environment may be greater than
room ambient. Therefore, consideration should be given to installing this PDU in
an environment compatible with the maximum specied ambient temperature.
Reduced Air Flow - Installation of this PDU in a rack should be such that the amount
of air ow required for safe operation of this PDU is not compromised.
Mechanical Loading - Mounting of this PDU in the rack should be such that a
hazardous condition is not achieved due to uneven mechanical loading.
Circuit Overloading - Consideration should be given to the connection of this
PDU to the supply circuit and the eect that overloading of the circuits might have
on overcurrent protection and supply wiring. Appropriate consideration of PDU
nameplate ratings should be used when addressing this concern.
Reliable Earthing - Reliable earthing of this rack-mounted PDU should be
maintained. Particular attention should be given to supply connections other than
direct connections to the branch circuit (e.g. use of power strips).”
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POWERING TECHNOLOGY
13.0 SETUP AND TESTING
13.1It is not necessary to have the PDU mounted in a rack for initial testing. This can
be done on a bench. It is also not necessary to have loads connected to the panel
for this testing.
13.2 With the input power source o, connect the input wires to the PDU. Set all circuit
breakers to on.
13.3
Turn on the input power source. Check the output voltage at each set of output
terminals with a digital voltmeter.
13.4 Switch o all circuit breakers and disconnect the AC source.
13.5 The PDU may now be connected to its intended application.
13.6 If the distribution panel did not operate properly in the above tests, go back and
double check the connections to make sure it is correct.
PDUAC3U SERIES
OPERATING MANUAL
Please note that there are no user serviceable parts inside either the modules or the shelves
and that opening either will void the warranty. If you are unable to resolve any problem
call your nearest UNIPOWER sales oce for support:
US +1 954 346 2442 UK +44 1903 768200
technical.support.repair@unipowerco.com
This document is believed to be correct at time of publication and UNIPOWER LLC accepts no responsibility for
consequences from printing errors or inaccuracies. Specications are subject to change without notice.