FRANKLIN – One Franklin engineering company took on the challenge of creating the brightest LED beacon in the world that sits atop the Freedom Tower in New York City, the tallest building in the Western Hemisphere.

Now, Carpe Diem Technologies has parts of the beacon that shines light from the skyscaper - also called One World Trade Center - back on their bench for repairs.

CEO John Berg and his team designed the lights for the Freedom Tower when it was constructed, starting in 2006, after the World Trade Center complex was destroyed by the 9/11 attacks. The beacon they created remains the brightest in the world.

It was a challenging job. Including the observation deck and antennae, the building reaches 1,776 feet into the sky to celebrate the year that the Declaration of Independence was signed. It has 104 floors and 94 actual stories.

The lights of the beacon are installed about 400 feet above the observation deck, Berg said. There is a ring of lights, about 8 feet wide when arranged, on the bottom of the beacon, and above those, another smaller set. Together they produce light that's reflected off two mirrors on each side of the beacon, creating a beam that is visible from 50 miles away.

“It is the brightest LED light ever built,” Berg said, as he turned the beam from an already blinding 25 percent power to make it brighter and brighter.

The complete beacon is divided into pieces, and each segment is called a petal. When arranged together, it looks like a flower. In total, there are 264 lights that create the beacon.

Berg said the LED light is very focused, in a laser-like fashion, a tricky thing to design, but possible using solid acrylic reflectors.

Now, pieces of the beacon are being returned to Berg’s shop so the company can figure out a way to stop lightning strikes from causing damage to the lights. Berg said the building is struck a few times during every storm because the building's enormous height naturally attracts lightning.

“If you Google it, you’ll see picture after picture of these spectacular lighting strikes,” he said.

The average lightning strike on the tower contains about 50 million volts, Berg said. After lightning hits a rod on the spire of the Freedom Tower, the voltage is greatly reduced, but does not completely dissipate.

“If you’re near it, you’re still going to get thousands of volts,” he said.

Using a Van de Graaff generator, basically a mini-lightning simulator, Berg can shock his prototype to test it. He showed how he added a device to one of the lights that stops electricity from spreading through the LED.

“Think about it like high-pressure steam,” he said. “We basically added a relief valve.”

With the new changes, he said, the excess electricity will be contained before it’s able to damage the LED. Hopefully, this will mean the lights can go years without another repair of this nature, he said.

As they climb up to collect and take down the petals for repair, workers must wear special suits to protect them from microwaves emitted from the tower's antennae on the tower, Berg said.

"If you get close enough to any of those antennae, you'll get cooked like microwave popcorn," he added.

The petals will then be shipped to Carpe Diem for repairs. The company is currently evaluating the scope of project.

Berg said this isn’t a project he did for the money, since he’s hardly made a profit, but rather about passion.

“In a way, it’s a tribute to what happened on 9/11,” he said. “It was a project that a lot of people didn’t want to do. I think they were afraid of the project.”

Scott Calzolaio can be reached at scalzolaio@wickedlocal.com or 508-734-0389. Follow him on Twitter @ScottCaz