Peco and representatives of the three biggest smart-meter manufacturers indicated the overheating problems are most likely caused by "external" problems in the panels mounted to walls into which the meter is plugged, not by a defect in the device itself. Peco says that fires caused serious damage in two homes when flames spread beyond the meter panels.
Innocenzo said the $650 million program, supported by a $200 million federal stimulus grant, is the largest technology investment in Peco's history. "We are committed to doing this well and doing it right," he told the commissioners.
He also told the commissioners the utility would pay for any damage associated with smart-meter installations. Peco has installed 201,642 of an initial deployment of 600,000 meters. Eventually, all 1.6 million Peco customers will get a device.
Peco's suspension of the program has attracted unwanted attention to a new technology that regulators consider a key ingredient to modernizing the state's electrical distribution system.
The meters, which take readings at least every hour and are equipped for two-way communication, allow utilities to improve outage management, to better understand energy consumption patterns and to fashion rate offerings to induce more efficient energy use.
The commissioners' mostly polite questions indicated they have no desire to undermine the statewide changeover to smart meters, which is mandated by a 2008 law. Smart meters have attracted opposition from some customers who worried about health effects of the wireless technology and loss of privacy, concerns that regulators say are overblown.
Robert F. Powelson, the commission chairman, said the meeting was intended only to gather information about the "isolated incidents" involving overheating meters, and public questions were not permitted. He praised Peco for being "extremely proactive" working with the PUC to determine the cause of the problem.
"This hearing is not a debate about whether or not to meter," he said. "We are moving forward with metering in Pennsylvania."
Commissioner James H. Cawley agreed. "We want this done," he said. "We want it done safely, of course, because the benefits to customers are enormous."
The manufacturers emphasized that 40 million electrity smart meters have been installed nationwide with few incidents. Peco has reported only a few dozen meters overheating out of more than 200,000 installed.
But Cawley's questions occasionally were pointed, as he asked Peco how contractors managed to install the new meters into customer-owned boards if they suspected there was a problem with loose wiring. Innocenzo said Peco had repaired 4,500 faulty boards, but some loose connections beneath the boards "are not always visible."
Peco and its primary meter vendor, Sensus Metering Systems Inc., of Raleigh, N.C., are rapidly installing software in the meters this month that shuts off electrical service in case the devices overheat.
Joseph McCormick, the Sensus vice president of North American operations, said the company had devised the fix after Peco and utilities in several other states reported overheating incidents.
"So the public can safely assume if this feature is installed on all the meters that they do not have to fear the meter overheating?" Cawley asked?
Innocenzo said that the new system had already worked - "several" customers had been shut off since the new safety measure was installed this month.
Peco initially reported that 15 meters had overheated when it suspended the installation program in August. Its latest count is that 29 meters have overheated, and that seven were caused by faulty wiring on meter panels, seven were caused by "localized" conditions such as water infiltration or tampering. Fifteen are still under investigation.
All incidents involved Sensus meters, which make up most of the devices the utility has installed. Peco has swapped about 30,000 of the Sensus devices with smart meters manufactured by Landis & Gyr AG to determine if one manufacturer's products are more susceptible to overheating.
Peco is also buying meters from Elster Group S.E. for industrial and commercial customers.
Peco says customers with concerns should call 855-741-9011.
Contact Andrew Maykuth at 215-854-2947, @Maykuth on Twitter or firstname.lastname@example.org.