A lightning arrester that failed at a substation on Sheron Avenue Monday night is to blame for a small fire and a power outage that affected the southeastern part of Rolla.

A lightning arrester that failed at a substation on Sheron Avenue Monday night is to blame for a small fire and a power outage that affected the southeastern part of Rolla.

Rolla Municipal Utilities (RMU) Rodney Bourne informed The Rolla Daily News that a total of 2,902 customers lost power for just over a half hour after 9:11 p.m. June 10 and another 784 customers in and south of the downtown area experienced a short "blink" in their electrical service.

That translates to about 30 percent to 40 percent of RMU customers that lost power or experienced a short outage.

Bourne said the arrester, which protects the transformer from being struck, failed on its own. There was no failure to the transformer, he said.

Bourne said the lightning arrester "went into full failure mode and tripped off a line that feeds five substations."

Bourne said power at his residence went off and a RMU board of public works member informed Bourne that he heard a bang from the incident. Bourne said the fire extinguished itself on the approximate 1-foot-tall arrester.

Crews from both RMU and City of Rolla Fire and Rescue responded to the substation on Sheron Avenue.

Bourne said two joggers who were running along a walking/bicycle trail near the substation and another individual saw the fire, which allowed Bourne and responding crews to find exactly where the problem was.

"I can't tell you how much those kind of calls help us if they can point us in the right direction," Bourne said, adding that without help from witnesses, it would take much longer for crews to locate the exact problem.

The lightning arrester has since been replaced, Bourne said.

During the outage, several people called the Rolla Police Department, which on its Facebook page, asked people not to call the 911 to report power outages and to remind individuals that 911 is for emergencies only.

Bourne also noted at night when outages occur, people may have trouble getting through to RMU because usually just one person is available to answer phone calls, but that employee also is working to get a hold of RMU crews to address the problem.

RMU's spring 2011 newsletter provided the following information for what to do when your power goes out and how to prepare for outages:

What to do if your power goes out

Take a deep breath. Wait a few minutes to see if the power will come on by itself. Many times it does.

If it does not, check your neighbors to see if they are off too.

If they are off too, no need to panic. RMU has a sophisticated system and we probably are already aware of the problem.

But, if you have heard or seen something that may be the cause of the outage, like a squirrel on fire or a tree limb in the lines, call and let us know. This information will allow our crews to get the power back on faster.

If your neighbors are not out of power, check your fuses or circuit breakers. If the fuses or breakers are good, report the outage by calling RMU. It is also important to report an outage during or after a major storm ... Be patient and call back after a couple hours have passed if the power hasn't been restored.

How can I be prepared for an outage?

Make sure you have at least one good flashlight. Better yet, make sure there's a flashlight on every floor of your home and one for each family member. Make sure the batteries are fresh ... Have a battery-powered radio with the appropriate batteries ready.

If you or someone you know depends on electrically-operated medical equipment, coordinate an emergency plan with friends and relatives. Have back-up power if you need it.