MLGW workers invent cost-saving pump system

The Commercial Appeal ran a great story on the solid state sump pump control that was developed by our employees and recently patented.

MLGW workers invent cost-saving pump system
Device saves equipment from underground floods

By Daniel Connolly

Originally published 12:00 a.m., February 18, 2012
Updated 12:09 a.m., February 18, 2012

Hidden under AutoZone Park is a "transformer vault," a big room full of electrical equipment.

"And we've got a picture of almost eight feet of water in that vault," said Roderick Truitt, 52, who works for Memphis Light, Gas and Water Division. Truitt said workers once ran pumps for two or three days to remove enough water to allow people to go in with hip waders and repair damaged equipment at the site.

Transformer vaults are common in dense urban areas such as Downtown Memphis. They contain equipment that converts electricity into a type of power that can energize nearby buildings. But these underground rooms often flood.

Truitt was among a group of five MLGW workers who invented a new way to bring such floods under control.

The U.S. government issued a patent on Nov. 1 for the team's "solid state sump pump control." The award capped a period of trial, error and applications to the government that had begun in 2004.

It's not the first time that MLGW workers have won a patent, but it's a rare event, and MLGW's board honored the inventors at recent ceremonies.

Besides Truitt, the inventors are Rick Cox, 49; David K. Morton, 53; Curtis Washington, 44; and retiree Alfred M. Bourell Jr., 65, who was a supervisor at the time the team began the work.

Members of the invention team all worked in the utility's electric motor shop, which Truitt compares to the military's special forces.

"Everybody has common talents and different talents where as a team, we can go in and get a lot of different jobs done," he said.

The five men received most of their tech training through two-year institutions such as the former State Technical Institute at Memphis, as well as the military and other certificate programs.

In a group interview, several of the men excitedly talked over one another as they described the invention.

"We wanted it to be the toughest ... " Truitt began. "Of the tough!" another worker interjected.

The inventors say they created the device to solve a practical problem. The underground rooms had pumping systems, including a control device on the wall that told the pump to turn on and off.

But water would sometimes rise so high that it covered the control system.

The result: a flooded vault and a ruined pump control system.

The pumps were designed to work underwater, and MLGW asked various companies if they sold a control system that could do the same.

There was no such device.

"So then we start discussing in the shop, 'maybe there's a way we can make what we want,'" Truitt said.

They invented a pump control device that's protected by a capsule that works like a diving bell -- even as water rises around the capsule, a pocket of air stays trapped inside and keeps the electronic components dry.

Transformers in the underground rooms can sometimes leak oil, and the new pump control system only pumps away water, not oil. MLGW wouldn't want to pump oil, a pollutant, into the wastewater system.

The utility makes its pump control devices by hand for a cost of about $300 each in materials, and has installed them in about 260 of the roughly 500 vaults around the city, the inventors said. The utility says the innovation saves at least $70,000 per year.

The patent protects MLGW from the possibility that someone will steal the idea and charge the utility money to buy devices that it currently makes itself, said Cox, one of the inventors. The utility is also considering selling the device on the market, MLGW spokesman Richard Thompson said.

"Any big city with underground utilities would have a need for this," said Morton, a member of the invention team.

Though the men's names are on the patent, the "intellectual property" belongs to MLGW, which means the workers wouldn't receive extra money if the utility sells the invention, spokesman Glen Thomas said.