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Precision Cooling For Business-Critical Continuity™

Liebert ® DCW ™ Family Chilled Water-Based High Density Cooling For The Data Center

Flexible Approaches For Energy Efficient Cooling

Save up to 70% in cooling energy usage

Normalized Annual Energy Usage

Data center managers are constantly faced with the challenge of reducing energy consumption and increasing processing capacity, without compromising business activities. The Liebert DCW chilled water-based high density cooling family provides energy savings of up to 70% over traditional cooling. The modular approach allows additional cooling to be added as compute capacity grows, without disruption of the data center.




70% in Energy

Adding targeted cooling is more cost-efficient than trying to lower the temperature of the entire data center by increasing the overall room air conditioning capacity. Liebert DCW missioncritical cooling systems are specifically designed to address the higher heat loads generated by tightly packed electronic rack enclosures.




Liebert DCW Water-Based Systems Liebert DCW is a family of water-cooled systems that offers a cost-efficient cooling alternative. They are designed to work in any size space from a small computer room to a large data center with loads from 5 to 35 kW per rack. Business continuity professionals are demanding an integrated high heat density cooling solution — one that considers both room-level and rack-level needs.

Effective Solutions need to be flexible Added as heat loads increase, Liebert DCW cooling capacity allows your facility to adapt as heat loads rise — allowing cooling solutions to be added to react to the changes in your environment.

Traditional Chilled Water Floormount

Liebert DCP + Liebert DCD System

Benefits of the Liebert DCW approach include: Lowest Total Cost of Ownership

Total energy savings potential of up to 70%

More cost-effective than increasing the overall room air conditioning capacity using floor-mounted cooling units only.

Minimal floor space requirements.


Can cool more than 35 kW per rack.

Designed to work with or without the hot aisle/cold aisle.

Works with or without raised floor.

Higher Availability


Ensures continuous operation of critical IT systems under extreme heat conditions

Local service and support experts, and 24 hour support call center

Total Data Center Cost (less land) Total Data Center Cost (less land) ($000) ($000)

Data Center Cost (New Construction)

Liebert DCW Solutions Cut Capital Costs

Fixed Load of 4,000 kW


Cooling System Building Cost Less Cooling

$25,000 $20,000 $15,000 $10,000

Data Center Cost (New Construction)

50 W/sq.ft 150 W/sq.ft 400 W/sq.ft Fixed Load of 4,000 kW (500 W/m ) (1500 W/m ) (4000 W/m ) $30,000 $5,000 Cooling System Investing in a facility that utilizes a higher rack density design — along with a cooling system designed especially for this 2



$25,000 $0 size and energy usage. type of installation — offers a significant cost savings advantage in terms of building

80,000 sq.ft. 8,000 m2


Building Cost Less Cooling 10,000 sq.ft. 1,000 m 2

27,000 sq.ft. 2,700 m 2

The flexible configuration of the Liebert DCW system modules also allows scalability andSize significantly Building $15,000 for future growth improves floor space utilization compared to an installation using only floor-mounted cooling units. Installing more $10,000 50 W/sq.ft 150 W/sq.ft 400 W/sq.ft Liebert DCW capacity uses little or no additional floor area. (500 W/m ) (1500 W/m ) (4000 W/m )

Cooling System Building Cost Less Cooling

$25,000 $20,000 $15,000 $10,000 $5,000 $0

50 W/sq.ft (500 W/m2)

80,000 sq.ft. 8,000 m2

150 W/sq.ft (1500 W/m2)

400 W/sq.ft 2 (4000 W/m )

27,000 sq.ft. 2,700 m 2

10,000 sq.ft. 1,000 m 2

Building Size

The capital costs of a data center are significantly reduced as higher densities of IT equipment are housed in smaller sized areas. Liebert DCW - Supplemental Cooling Requires less Chiller Capacity


Chiller Capacity Latent Load

kW Chiller Capacity per kW Of Sensible Heat Load

Fan Load Study — Data Center Cost (New Construction) 1.20 Sensible Load

400 racks with an average heat load of 10 kW each. Cost 1.00 for building, power, cooling, lighting, fire protection, 15% Lower 0.80 security, etc. included. Cost of land not included. 0.60

0.40 Building 1: 80,000 sq.ft. (8000m2), 18” (450mm) Raised 0.20 Floor, Designed for 50 W/sq.ft (500W/m2), Raised-floor 0.00 Precision Air Conditioning units for cooling. CW CRAC

Liebert DCW

Building 2: 27,000 sq.ft. (2700m2), 36” (900mm) Raised Floor. Designed for 150 W/sq.ft (1500W/m2), Raised-floor Precision Air Conditioning units for cooling. Liebert XD(1000m2), - Supplemental Building 3: 10,000 sq.ft. 18”Cooling (450mm) Raised wer to cool 1 kW of sensible heat

with Operating Costs Floor. Designed for 400Lower W/sq.ft (4000W/m2), Raised-floor Power Usage 0.60 Precision Air Conditioning units (for basic Fan cooling and Pump (XD) humidity control) and Liebert XD. Pump (CW) 0.50 Chiller

0.40 0.30 0.20 0.10

kW Chiller Capacity per kW kW Chiller Capacity per kW Of Sensible Heat Load Of Sensible Heat Load



Fixed Load of 4,000 kW



Liebert DCW -27,000 Supplemental Cooling 80,000 sq.ft. sq.ft. 10,000 sq.ft. Requires 8,000 m2 less Chiller 2,700Capacity m2 1,000 m 2


Chiller CapacityBuilding Size Latent Load Fan Load Sensible Load

1.20 1.00 0.80

15% Lower

Liebert DCW - Supplemental Cooling

0.60Requires less Chiller Capacity 0.40Chiller Capacity 1.40 0.20 1.20 0.00 1.00 CW CRAC 0.80

Latent Load Fan Load Sensible Load

Liebert DCW 15% Lower

0.60 One of the major areas of savings identified with the use of 0.40 Liebert DCW equipment is the ability to reduce chiller plant size. This is because 0.20 the chiller typically is sized for the total gross capacity 0.00 of theLiebert raised-floor cooling units. The 65% lower XD - Supplemental Cooling CW CRAC Operating DCW with Lower Costs fan load of the Liebert DCW System Liebert modules and the fact Power Usage in a capital chiller size savings of they are 100%0.60 sensible results Fan Pump (XD) 15% or more. kW power to cool 1 kW of sensible heat kW power to cool 1 kW of sensible heat

Total Data Center Cost (less land) ($000)

Data Center Cost (New Construction)




Pump (CW) Chiller

0.40 0.30

Liebert XD - Supplemental Cooling with Lower Operating Costs

32% Lower 0.20 Power Usage 0.60 27% LowerFan 0.10 Pump (XD) Pump (CW) 0.50 0.00 Chiller CW CRAC CW CRAC Liebert XD Liebert XD 0.40 at 100% at 50% at 100% at 50%






32% Lower 27% Lower

0.10 0.00


CW CRAC at 100% Capacity

CW CRAC Liebert XD Liebert XD at 50% at 100% at 50% Capacity Capacity Capacity

The smaller chiller plant and lower fan load result in significant energy savings as well. A 27% energy savings is very conservative.

32% Lower 27% Lower


High Heat Density. High Temperatures.

This compacted capacity means higher heat densities. What was once a 1 kW rack or 10 kW rack may now exceed 30 kW. This requires a shift in focus from a traditional room-based view of cooling to a rack-based view. IT decision makers must consider both “watt per square foot” and “kW per rack” when evaluating cooling solutions.

10,000 8,000 6,000 4,000 2,000 1,000 800 600 400 200 100 60

ity ens eD rem t x n-E icatio mun rs Com Serve r te u Comp ers rv e S ge ne) Stora ndalo ns (sta statio Work

Storage Servers Workstations (standalone)

Tape Storage

age Tape Stor













100,000 60,000 20,000 10,000 6,000 4,000 2,000


Year of Product Announcement

ASHRAE, Datacom Equipment Power Trends and Cooling Applications, 2005. © American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc.,

And, They Attack Your Facility in Two Ways Hotter Facilities Hot Spots As processor capabilities increase, so do computer room power densities—from 50 Watt per square foot (540W/m2) to over 300 Watt per square foot (320W/ m2). Your whole data center just keeps getting hotter.

50W to 300W


eme Density Communication - Extr and Custom Blade 1U, rs Serve Computer y Communication - High Densit and Greater 2U Computer Servers

Heat load per equipment footprint (watts/equipment sq.m.)

No Relief in Sight: Heat Loads Rising Heat load per equipment footprint (watt/equipment sq.ft.)

With constant introduction of new technology, the computing capacity that once filled an entire room can now be contained within a single rack. Blade servers, communication switches and other electronics are packed into racks — creating increased heat densities that cannot be effectively cooled by traditional cooling solutions.

The Liebert DCW cooling solution can provide 200 kW of sensible cooling, with modules capable of providing localized cooling up to 35 kW per rack.

Compounding the problem, this higher heat load is not evenly distributed throughout the room. Sometimes, power densities can grow into hundreds of Watt per square foot, creating localized “hot spots” of extreme heat.


Room-Neutral Cooling













80 / 27 73 / 23 66 / 19 60 / 16

Heat Load = 3 kW Per Rack With Hot Aisle /Cold Aisle Layout ˚F ˚C








98 / 37 88 / 31 79 / 26 69 / 21 60 / 16 Heat Load = 6 kW Per Rack With Hot Aisle /Cold Aisle Layout ˚F ˚C COLD AISLE






115 / 46 HOT AISLE

The Liebert XDK-W enclosed rack contains and cools the hot air within the cabinet.

˚F ˚C 87 / 31


70 / 21

Heat Load = 3 kW Per Rack Without Hot Aisle /Cold Aisle Layout


The Liebert DCD door neutralizes the server’s exhaust air before it leaves the rack.

80 / 27 60 / 16


90 / 32


Some room and equipment designs preclude the hot aisle/cold aisle configuration. These are often well-suited to cooling with the Liebert DCW system.

˚F ˚C 100 / 38


A common way to improve performance of existing raised floor cooling applications has been the “hot aisle/cold aisle” approach. In this configuration, rows of equipment racks are arranged in alternating “hot” and “cold” aisles. Only the cold aisles have perforated floor tiles that allow cool air to come up from under the raised floor. The Liebert DCW solution is compatible with existing hot aisle/cold aisle application.

Unfortunately, even when using a hot aisle/cold aisle configuration, the limits of standard underfloor cooling are soon reached as rack heat loads increase.

101 / 38 87 / 31 73 / 23 60 / 16

Heat Load = 10 kW Per Rack With Hot Aisle /Cold Aisle Layout Side views of Computational Fluid Dynamics (CFD) by Fluent showing limitations of hot aisle/cold aisle approach as heat load increases.


Liebert DCW Cooling Solutions

200 kW of Sensible Cooling The Liebert DCP Coolant Pumping Unit is the key to the performance, efficiency and space saving design of the Liebert DCD passive chilled water door and Liebert XDK-W water- cooled rack enclosure. The unit houses the isolating heat exchanger between the Liebert DCD/XDK-W circuit fluid and building chilled water, the control valve, the dual redundant pumps and the system controls. It controls the fluid temperature above the actual room dewpoint. The Liebert DCP can also be used with other brands of rack cooling equipment.

Building Chilled Water Building Chilled Water

Liebert DCP Pumping Unit

Liebert DCP Pumping Unit

Liebert DCD or Liebert XDKW Chilled Water

Liebert DCD or Liebert XDKW

Liebert DCD or Liebert XDKW Chilled Water

Liebert DCD or Liebert XDKW

The Liebert DCP isolates the building’s chilled water circuit from the chilled water circuit within the data center. Separating the data center from the building chiller also minimizes the impact of a leak within the data center. Should a leak occur, the volume of water is limited to the amount within the secondary piping system instead of the entire building chiller system. The separation from the building chiller system also ensures proper water quality to the cooling modules in the data center by creating a closed loop system. The Liebert DCP circulates the chilled water to cooling modules (Liebert DCD or Liebert XDK-W) while preventing condensation by maintaining the water temperature above the room dew point.

Intelligent System Control The Liebert iCOM control system on the Liebert DCP features maintenance history, spare parts list, Liebert IntelliSlotÂŽ for up to two cards (web compatibility and BMS), and comprehensive monitoring. The enhanced Liebert iCOM with its IT-focused user interface allows real-time monitoring and data capture. Status may be reported back to the BMS via Liebert IntelliSlot communications cards.


Room-neutral Cooling Over 35 kW Per Rack High density cooling that won’t add heat to your room.

Liebert DCW Cooling Modules Open Architecture Liebert DCD Rack Door Cooling Module Replaces the back door of a server enclosure, providing cooling without increasing the rack footprint. The module uses the server fans within the protected rack to provide airflow, providing the most energy efficient design.

Can cool over 35 kW per Rack No electrical components No noise Stationary connections Full access to rear of rack Adapts to Emerson Network Power DCM racks or racks by other manufacturers

Closed Architecture Liebert XDK-W High Density Cooling Enclosure Utilizes closed air circulation, the racks are completely sealed from room air. The server heat load is dissipated into the process chilled water system through an air-towater heat exchanger in the bottom of the rack. Redundant high-performance fans drive closed loop air circulation in the rack’s interior, while servers are supplied with cold air at the front of the rack.

Can cool over 35 kW per Rack Completely sealed rack N+1 redundant variable speed fans Quiet operations Automatic emergency door opening

Open and Closed Architecture Systems as defined by ASHRAE

Open architecture systems utilizes cooling coils near the heat load either inside or outside the open server rack and use the room air volume as a thermal storage to ride through short power outages.

Closed architecture fully encloses the rack with the cooling coils inside. Other provisions are required for power loss ride through.

For refrigerant-based systems, the Liebert XD system is designed to maximize cooling efficiency while avoiding the electrical hazards that may be present in a water-based system. The Liebert XD system can cool rack loads from 8 to 40 kW per rack in rooms 1200 sq ft or larger. (See Liebert XD Brochure SL-11265 for more details.)


Emerson Network Power, a business of Emerson (NYSE:EMR), delivers software, hardware and services that maximize availability, capacity and efficiency for data centers, healthcare and industrial facilities. A trusted industry leader in smart infrastructure technologies, Emerson Network Power provides innovative data center infrastructure management solutions that bridge the gap between IT and facility management and deliver efficiency and uncompromised availability regardless of capacity demands. Our solutions are supported globally by local Emerson Network Power service technicians. Learn more about Emerson Network Power products and services at

Emerson Network Power Liebert Corporation World Headquarters 1050 Dearborn Drive P.O. Box 29186 Columbus, Ohio 43229 United States Of America 800 877 9222 Phone (U.S. & Canada Only) 614 888 0246 Phone (Outside U.S.) 614 841 6022 FAX Emerson Network Power European Headquarters Via Leonardo Da Vinci 8 Zona Industriale Tognana 35028 Piove Di Sacco (PD) Italy 39 049 9719 111 Phone 39 049 5841 257 FAX Emerson Network Power Asia Pacific 29/F, The Orient Square Building F. Ortigas Jr. Road, Ortigas Center Pasig City 1605 Philippines +63 2 687 6615 +63 2 730 9572 FAX 24 x 7 Tech Support 800 222 5877 Phone 614 841 6755 (outside U.S.) While every precaution has been taken to ensure accuracy and completeness in this literature, Liebert Corporation assumes no responsibility, and disclaims all liability for damages resulting from use of this information or for any errors or omissions. © 2011Liebert Corporation. All rights reserved throughout the world. Specifications subject to change without notice. All names referred to are trademarks or registered trademarks of their respective owners. ® Liebert is a registered trademark of the Liebert Corporation. SL-17355 (R12/11)

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Liebert DCW Family Brochure  

Liebert DCW Family Brochure

Liebert DCW Family Brochure  

Liebert DCW Family Brochure