Magazine Article | May 1, 2000

Uninterruptible Power Supplies Solve Grocery Store's ‘Noise' Problem

Food Mart's compressors operated its refrigeration units, but wreaked havoc with the store's point of sale (POS) system. Installing power protection devices throughout the networked system quickly controlled the problem.

Business Solutions, May 2000
Dave McCarthy didn't anticipate any power problems when his company, DUMAC Business Systems, completed an installation at the Food Mart in Corning, NY. After all, DUMAC Business Systems (Syracuse, NY) had a company policy that requires its customers to use power protection devices for the PCs and to have proper wiring. Point of sale (POS) systems integration company DUMAC Business Systems, founded in 1952, specializes in the grocery, hospitality, and retail markets. The family-owned company has 54 employees at its three locations in New York state. McCarthy is the company president.

McCarthy doesn't install point of sale (POS) hardware unless the electrical specifications have been met. "We require our customers to have clean power – power that is free of noise - and isolated ground wires," said McCarthy. "Food Mart had met all of our initial electrical requirements; however, the POS system we installed kept locking up." Food Mart is owned by Olean Wholesale Grocery Cooperative, Inc. Corning, NY is home to the Corning Museum of Glass and approximately 15,000 people. Food Mart is located in a heavily traveled tourist area of the city. According to Food Mart Manager Brian Wilson, the store has 10 checkout lanes, including four express lanes. The store is open seven days a week. DUMAC Business Systems replaced Food Mart's NCR POS terminals with NCR's networked ScanMaster terminals in all 10 lanes. Dumac also installed commercially available uninterruptible power supply (UPS) devices on the server, the EFT (electronic funds transfer) terminal, and three back office computers. Shutdown software was also included. In the event of a power failure, Food Mart would have an orderly shut down of its POS system. The store could continue to operate for approximately 20 minutes after a power failure.

Refrigeration Compressors vs. POS System
So what was causing Food Mart's new POS system to lock up? McCarthy was puzzled. "Something was causing noise in the power lines and shutting down the system," said McCarthy. Two representatives from POWERVAR, Mark Engle and Mike Ference, visited McCarthy at Food Mart to help solve the problem. "We used a device called a Drantz meter and a special Oscilloscope from POWERVAR to check the store's power lines for noise," explained McCarthy. "The noise was coming from the large compressors in the store's basement." The bank of wall-high compressors, which cannot be moved, runs the store's refrigeration units. The solution was to add more UPS devices. "A POWERVAR UPS was attached to each POS terminal, PC terminal, and PC workstation on the network," said McCarthy. The results were immediate; the system lockups stopped.

Overcoming Obstacles To UPS Sales
McCarthy is adamant about including power protection devices in every sale. "The customer can spend the money on the UPS devices up front, or pay more for an electrician later," he said. McCarthy also uses POWERVAR's GroundGuard product. GroundGuard eliminates the need for both dedicated electrical circuits and isolated ground wiring.

McCarthy's salespeople initially balked at his policy of always incorporating power protection in a sale. "Now the salespeople include UPS devices in their quotes," said McCarthy. "Using power protection in our systems has cut down our service calls by 95%."

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