April 09, 2020

Technology, safety spare phone lines

It was an obvious question, and Vice President Al Gore took a stab at it Thursday:

How is it that this winter’s cataclysmic ice storm, which took power and heat from scores of Maine households, left phone lines relatively unscathed?

The answer, according to Maine power and telephone officials, is complicated — a little bit safety, a little bit technology.

First, take a good look at a utility pole. Most form a totem: telephone on the bottom, cable in the middle, electric on top. That way, if an accident such as a fallen tree occurs, people will be protected from electrocution.

Electrical wires carry current — 12,000 to 345,000 volts worth. Telephone wires carry information and have little in the way of voltage.

“You can touch a telephone wire,” said George Baker, manager of engineering for Bangor Hydro-Electric Co. “If you touch an electrical wire, you’re dead.”

If a tree so much as touches an electrical wire, it might look spectacular — blue arcs lighting up the night like fireworks. But in the span of a millisecond, the wire’s current will hit the ground, touching off a breaker and causing a power outage.

Telephone lines, meanwhile, buffered by their proximity to the ground, are insulated and are lodged to their utility poles with thick metal strands. “That’s pretty darn rugged,” said Dan Breton, spokesman for Bell Atlantic of Maine. “It’s unlikely anything is going to break through that strand and get to the wires.”

As long as the wires hold together, a telephone line can work just as well on the ground as it does in the air.

In an ice storm, electrical cables are like the front lines in a war — first to be hit and first to go. Telephone service, on the other hand, both relies on electrical current and can work without it.

In cities like Bangor, telephone service is run by a tower of batteries — each the size of a dishwasher — that feed off commercial power. When outages occur, an emergency generator kicks in and gives them life. On their own, the batteries can last from eight to 24 hours.

“Those generators can run infinitely,” Breton said. “So there’s no immediate problem when the power goes out.”

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