Data Center Design/Build Firm Presented With A Rare Challenge
Reliability is the ability of a system to routinely perform and maintain its functions even in unstable environments or unexpected circumstances.
By ASCO Power Technologies
Every professional holds a special place for reliable systems. Even the Yellow Pages dedicate commercials to reliable people and companies and how to identify “the good guys.”
So when Technology Site Planners (Tech Site) received a phone call from a client to design and build a highly reliable data center in a former warehouse, they anticipated a number of challenges coming their way.
Tech Site is an engineering design / build firm that specializes in evaluation, design, construction and post-construction services for business-critical facilities.
The client, a global company located near Cincinnati, Ohio that processes orders and tracks materials for several subordinate enterprises, has worked with the design/build firm for several years.
“The client retains us to help ensure reliability of their current data center,” said William W. Schrader, a project engineer with Tech Site. “We are professionals whose expertise lies in designing and building data centers.”
The client required a 4,000 sq. ft. data center be designed and built from the “ground up” within the warehouse and be fully operational in six to seven months. An impossible task? Typically, that size data center would require a minimum of nine to 12 months to design, build and commission. The firm was confident the work could be accomplished within the short time frame, but knew it would require a colossal effort from all the vendors they would work with on the project.
The company accepted the challenge and immediately faced two considerable hurdles.
First, they needed to devise a strategy which would ensure the short timeline could be met. The client’s current, aged data center already operated over capacity. Additionally, they wanted to consolidate data processing services from other companies they had acquired. That’s why the client needed another data center up and running almost immediately. The firm suggested the design reflect a data center that could be doubled in size to 8000 sq. ft. to accommodate further growth, modifications and equipment additions. The client agreed.
The base design would use only half the space and have a designed energy consumption level of 100 watts sq./ft. The remaining 4000 sq. ft. would provide the ability to upgrade the data center’s power system in the future by replacing or adding additional equipment.
The company’s second hurdle: build the data center without exceeding the recommended budget in the demanding timeline. While this is always a challenge, the expedited deadline left no room for error.
Tech Site and the client decided the best approach to address the time frame and budget challenges was to go with a flexible design that would be modified and finalized while initial construction was underway.
“We had a design in place but we were still finalizing portions with the client and we were working with vendors and contractors to complete all the specifications and agreements. The company focused on the critical path items. We knew going in that some of the engineering and project management would be ‘on the fly.’ This requires an experienced project management team working closely with our engineering department and a high level of trust in and cooperation with our vendors. It becomes a real team effort,” Schrader said.
Needless to say, the firm knew this would be one of the most creative and challenging assignments they had ever accepted and it would test their project management skills to the limit.
Just as the client depended on the company’s reliability, Tech Site sought reliability from each manufacturer and service company in terms of equipment costs, expedited delivery and responsive customer support. The company had vendors bid on the project to ensure it stayed within the budget, of course, but they selected only the absolute best vendors from each industry. With little to no margin for error, the firm demanded to work only with industry leaders.
Construction on the data center began with redesigning the facility-side feed from the utility source, which comprises a single substation, roadside utility vault and utility transformer. The utility transformer dropped 3 phase power to 12.5 kV, 200 amps for parallel runs to two, independent transformers that serviced the warehouse.
Data center best practices call for a dedicated transformer and this project was no exception. So a new, pad-mounted 2500 kVA transformer was installed for the data center.
Inside the building, utility power feeds a switchboard that distributes power to two main transfer switches through separate breakers, each breaker supplying power to the “normal” side of one transfer switch. These transfer switches establish a dual bus power feed arrangement to provide reliable, redundant power to the data center.
After establishing the utility power source, a 1250 kVA, 1000 kW generator was selected and placed, with space set aside for a second generator in a subsequent expansion. The generator feeds a switchboard that also distributes power to the two main transfer switches. It features an input from the existing generator and two 3000 amp breakers that independently feed the emergency side of the transfer switches.
The distribution switchboards keep power flowing, through the uninterruptable power supplies (UPSs), to the 75 server racks that manage information for national and international customers. Power also is supplied to four command center office units: a “War Room,” print room, build room and the data center command and control room. A 230 amp secondary transfer switch directs power from both busses to lighting panels and generator-backed receptacles. In addition, each CRAC unit is powered by a dedicated transfer switch that is supplied from both of the dual bus power feeds. Under normal conditions half of the CRAC units are fed from power bus “A” and half from power bus “B”. In the event one bus fails, the CRAC transfer switches shift all CRAC units to the remaining bus to retain full cooling capacity.
During the construction phase, many adjustments occurred to accommodate the budget and schedule. As the firm and the client expected, vendors reacted well to last-minute changes.
”Some of those last-minute changes came right down to the wire, too,” Schrader said. “After we ordered the ASCO Transfer Switches, for example, I would go back to the company to discuss necessary modifications as the project progressed and they made the changes.”
The main transfer switches are of the closed-transition transfer, bypass-isolation mode of operation. The bypass-isolation capability allows these transfer switches to be maintained and tested while they are hot to ensure power continuity to critical loads. Each is rated at 3000 amps, 480 volts and features 3 phase, three-pole architecture. The majority of the critical power infrastructure is designed for 3000 amp service.
Three thousand amps are about twice what the first half of the data center will need, but it will save money in the long run. As the center expands, it will avoid the expense and difficulty of replacing not only transfer switches, but cabling, bus duct, switchgear and transformer.
The dual busses are independent of each other and each bus feeds power to its own 500 kVA UPS unit.
“The distribution switchboards and the floor plan in the UPS room are designed with the intention of replacing both UPS units with 1000 kVA models,” Schrader explained. “Everything about this new data center is ready to accommodate or can be replaced to accommodate an 8000 sq. ft. mission-critical facility without disrupting data center operation.”
To ensure selective coordination of breakers throughout the facility, the firm decided that any breaker greater than 400 amps would have a long, short, instantaneous and ground (LSIG) fault trip on it. This ensures that if a fault occurs downstream, the breaker will open to minimize equipment damage by preventing tripping further up the line.
After completing construction, the client contracted with Tech Site to provide maintenance services to the data center.
Tech Site and the client monitor the facility’s critical functions such as the generator, switchboards, utility power and transfer switches. The Ethernet-based monitoring system also tracks power usage of equipment within the infrastructure, giving both parties an accurate status update.
“When we selected vendors at the beginning of the project, we knew we would need these vendors and their service and support as well,” Schrader said.
The company looked for vendors with well-established service reputations who would be available in the middle of the night or early morning hours to resolve an issue immediately.
“That’s just one of the many reasons the firm recommended to the client that we go with ASCO for the transfer switches.” Schrader said. “Their customer support is extremely responsive and ASCO Services has an impeccable reputation.”
In all, the company pulled off an incredible victory with their team of reliable vendors. When it comes to designing and building data centers with less than ideal and unexpected circumstances, Tech Site is “one of the good guys.”