Lack of outage warning a concern
Safeguard gave no alert before Lake Worth’s April 9 blackout.
LAKE WORTH — The biggest fail of Lake Worth’s mysterious power outage two weeks ago for Lake Worth utility officials wasn’t the failure of an 8-foot-tall current transformer, which caused more than 26,000 customers to be in the dark for hours.
Rather, it was the lack of a warning signal — much like an engine service light or low gas indicator that pops up on automobile dashboards — that baffled officials.
Those warning signals are supposed to act as a safeguard.
“Up until two seconds prior to the failure, there absolutely was zero indications that this device was breaking down or beginning to fail,” Utilities Director Ed Liberty told city commissioners at Tuesday’s meeting. “Electrically, it was performing absolutely fine. That is a concern.”
The April 9 incident at the Hypoluxo substation came at 11:10 p.m., when the transformer, a device that measures the amount of amps flowing through a conductor, failed — “catastrophically” as one official put it.
“It’s unusual for these devices to fail in this manner,” Liberty said. “There was a large fireball.”
The fault current from the device caused an overhead static wire to melt and come down across the tie line 18 seconds later.
The result was an inconvenience that put many in Lake Worth out of power through most of the night — creating less-than-ideal sleeping conditions for a community used to air conditioning in 80-degree April temperatures.
Not counting Lake Worth, Liberty said more than 43,000 customers were affected instantaneously, including those living in Lantana, Boynton Beach and Quantum.
Liberty said power was fully restored at 6:47 a.m., halfway through the morning rush hour, which caused some traffic problems at intersections where stoplights failed, especially those near Palm Beach State College.
Very few residents, Liberty said, were without power from 11:10 p.m. to 6:47 a.m. Close to 50 customers were restored by 11 a.m.
“We had some problems with some circuits that were overloading as we were bringing them back into service,” he said. “If you can imagine for a period of six or seven hours, refrigerators are off, air conditioners are off, and when you first start them up, they experience a large inrush of cur- rent and that could overload the circuit.”
Liberty added the defective device will be sent to an independent lab for forensic analysis that will determine the root cause and if the city should remove the other two devices from service.
“We see no indications on those devices that they are about to fail,” Liberty said.
The failed transformer was not a new device and had been used previously. It has been stored for a number of years, but the city said tests said it was OK, Liberty said.
When the fire started, Lib- erty said it was decided to let the fire burn itself out rather than approach the substation or pour water on it.
“It was a good decision that was made,” he said. “We were able to put the fire out with a hand-held fire extinguisher.”
Workers began cleanup and repairs as soon as the line was isolated and made safe, Liberty said. All insulation in the fire’s area had to be wiped down to remove soot and to prevent a flashover once the system was started.
“It was outstanding electric teamwork,” Liberty said. “I don’t think anybody was worried about whose device failed and who was to blame. The focus was on safety, containing and returning customers to service as quickly as possible.”