Cooperative News

Reliability on the lines: lightning arresters

These simple devices reduce outages by protecting expensive equipment

They may not look like much from below. But they’ve prevented outages, saved our equipment and protected your home electronics more times than we can count.

Lightning arresters — the squat, screw-shaped devices you may notice on our lines and around our transformers — are a relatively cheap and simple technology. But when it comes to keeping voltage spikes at bay, they pack a mighty punch.

“It’s a self-sacrificing device designed to protect much more expensive equipment,” PEC Technical Services Manager Bryan Harbuck explained.

How do they work?

Each lightning arrester is designed to allow only a certain voltage of energy to pass. If extreme, high-voltage energy tries to travel through, the arrester breaks apart, creating a temporary fault in the system (a quick, “blink”-style outage) while it channels the excess energy to the ground.

So instead of that lightning bolt blowing up an expensive piece of equipment like a transformer — or traveling to your house and frying your electronics — it’s halted in its tracks by a simple, inexpensive device.

Or, to be more precise, by a fleet of devices: PEC has upwards of half a million lightning arresters in the system.

“Let’s say a lightning strike occurs here [in Johnson City] without any arresters,” Harbuck said. “Cedar Park would see it. A wide area of the grid would see it. It’s just that by the time the strike has passed through all those lightning arresters, the voltage spike has been quelled so far that Cedar Park doesn’t really see anything.”

In addition to saving money by protecting expensive equipment — savings we pass on to our membership — the lightning arresters help prevent the lengthier outages that accompany transformer and other major equipment damage.

“With the terrain we have here in our service territory, lightning storms are a present threat,” PEC Technical Services Supervisor Eric Bitzko said. “A strike really does affect everybody that has a meter on our system. The arresters are one way we help mitigate that.”