A couple of electrical contracting firms from the community of Minot, Main Electric Construction Inc. and Holmes Electric, began working on the original construction of the base, and just like the Air Force, have been there ever since. While the two firms were competitors in the 1950s, they have been a single entity since 1979, when Main Electric bought out Holmes Electric.

“We’ve been there at the Air Force Base since the first shovel was turned,” said Bill Brunner, Main Electric Construction Inc. vice president. “There are few buildings on that base that Holmes or Main have not been involved with over the years.”

“We pretty much have 10 to 15 guys out there all the time,” said Brunner. “But all of the work still goes out to bid,” he said, an attestation to the satisfaction of the owner with their electrical contracting services.

Currently, Holmes Electric is working on the new Security Forces Vehicle Building at Minot AFB, which is scheduled for completion by July 2007. The project includes 58,000 square feet of parking garage and 3,500 square feet of office/classroom space. While the companies have had completely integrated operations since earlier this decade with Main Electric as the official name of the corporation, they still use the two different company names, depending on the project.

Vehicle building install

Work on the Security Forces Vehicle Building, which is a U.S. Army Corps of Engineers project, began outside of the actual building footprint. The existing base power distribution grid near the site of the new building was above ground, but the military wants to continue to move away from exposed power to buried lines.

The first step in the project was to remove about 1,000 feet of overhead primary conductor on five poles and install about 2,000 feet of primary feeder in underground concrete-encased raceway with above-ground sectionalizers or transformers. That included a four-way distribution switch that ties into the existing overhead distribution system. Cooper Power Systems provided the primary distribution system materials.

Electricians also installed a 300 kVA, three-phase, four-wire 12.5 kV primary service-entrance transformer where the voltage steps down to a 480V, three-phase, four-wire main distribution system. The company then installed three step-down 480V to 120/280V transformers. Siemens provided the electrical switchgear, the interior distribution system materials, the motor control systems, the electrical panels and the smaller electrical transformers. All of the interior electrical equipment is mounted in the building’s single 6-by-6 foot electrical room.

Fiber deployment

The outside work also included an Optical Cable Corp. 12-strand single-mode fiber optic cable into the building from an outdoor pedestal that will cross connect into base fiber optic network infrastructure; the fiber will service both of the building’s computer and telephone communications systems. Holmes already terminated both ends of each fiber with ST connectors for cross connection; termination devices were produced by 3M.

The company also installed cathode protection for corrosion control on all of the building’s underground mechanical systems, using devices from CP Solutions Inc. Inside the structure, all electrical and low-voltage cables are being installed in conduit.

“That is pretty typical for the military, because it really likes the added security that comes with eliminating exposed cable,” Brunner said.

Lithonia Lighting provided all of the lighting devices on the project. In the office and training areas, there is a tile-drop ceiling into which the electrical crew is installing energy-efficient T8 fluorescent lamps with electronic ballasts. The installation also will include 400W metal halide high-bay lamps in the parking garage and single 250W metal halide high-bay lamps on seven 30-foot poles in the outside parking lot. On the walkways, Holmes will install 16 42-inch lights, each with a 70W metal halide lamp.

One unusual element of the building’s design is its use of ground-source heat pumps for heating and cooling.

“The heating and cooling system in this building must be remarkably robust, especially in the outdoor parking garage where the temperatures can really dip,” said Ray Johnson, project electrical specialist in Minneapolis for Leo A Daly, the architect and engineer on the design/build project and one of the 10 largest architecture, engineering, planning and interior design firms in the United States.

The ground-source heat pump system uses six 200-foot wells that provide heating and cooling for the facility. Holmes Electric has provided the electrical hookups for both the circulating pumps and controls of that system.

In addition to the interior electrical system, electrical contractors installed the building telecommunications cabling using Hitachi Category 6 cabling and Leviton termination devices. There is one telecommunications room with a single LAN rack, and the network includes about 50 voice and data drops. The largest concentration is in a classroom/training facility.

It’s no surprise that a building for Air Force Security Forces will include a stalwart access control and intruder alert security system, provided by SimplexGrinnell. Holmes will install the entire system, which includes electronic strike door locks throughout, along with touchpad entry devices and a microphone paging intercom at each of four personnel entrances. The building fire alarm also is from SimplexGrinnell, and it will be programmed and certified by the manufacturer after Holmes electricians install all of the system cabling and devices.

The Cold War is over, but there is still plenty of work for the U.S. Air Force around the world, so it appears Minot AFB will be there for some time. Together, as a single entity serving distinct and different electrical contracting functions is the way Main Electric and Holmes Electric get the job done effectively for government, military and a host of other customers.