The grounding slot is important for devices with a metallic casing or metal-cased power supply, like computers. The grounding wire is connected much like the neutral, as it also connects to a grounded neutral tie block. Most modern sockets in North America have a grounding slot in addition to the hot and neutral(see figure 3). In a non-polarized plug, the switch may only open the circuit at the neutral lead, which means that most of the internal circuitry of the device is still considered "hot" and can lead to shock hazards. The benefit of polarization is that polarized plugs can only be inserted in one orientation, so the switch to turn any device connected to the socket on or off can be built into the hot lead. Of course, to complete the circuit all the way back to the generator, the neutral is also connected back to the original distribution system in addition to being grounded at multiple locations. Instead, the hot slot supplies the voltage required to draw current, and when a plug is inserted into the socket, the energy flows in from the hot slot, through the circuit, and ends at the neutral, which disperses the energy into the ground. The neutral is connected by a wire to ground, so its voltage is 0 V. In North America, this is accomplished by having two differently sized slots in addition to the rounded grounding slot, the larger of which is called the neutral line, and the smaller called the hot line (see figure 2). Polarized plugs can only be inserted into them one way (which seems annoying, but is actually an important safety feature). A labelled diagram of a polarized two-pronged outlet. The panel later retreated under opposition from Manchin and Senate Republicans.Figure 2. Manchin also blasted a move by FERC’s Democratic majority to more closely scrutinize the impact of natural gas projects on climate change. Manchin, a strong supporter of fossil fuels, sharply criticized Biden’s remarks about shutting down coal plants and replacing them with renewable energy. Manchin, a West Virginia Democrat, has not given a reason for his refusal, but a spokeswoman said last month that “the chairman was not comfortable holding a hearing.″ Joe Manchin, chairman of the Senate Energy Committee, has refused to schedule a confirmation hearing. President Joe Biden renominated Glick to another term as chairman, but Sen. Thursday’s meeting was likely Glick’s last as chairman, after his term expired earlier this year.
Glick, a Democrat, told reporters after the meeting that while he is always concerned about costs: “How concerned are you about the cost when the power goes out? Would you rather pay now or later?″
“I hope this does not flow through to ratepayers,″ he said. The substations are a different ballgame.″ Power transformers are highly visible in thousands of sites across the country and “are really vulnerable - sometimes to a drunk with a gun and an attitude,″ said FERC commissioner Mark Christie. Grid security experts have said the attacks demonstrate anew the vulnerability of the nation’s electric grid, which includes more than 50,000 substations and more than 700,000 miles of transmission lines. Attackers used firearms in at least some of the incidents, and some power customers in Oregon temporarily lost service. Law enforcement officials say they have found no evidence linking incidents in the two states, although multiple state and federal agencies continue to investigate.Īt least four electrical substations have been targeted in separate attacks in Oregon and Washington state since November, Oregon Public Broadcasting and other outlets reported. 7 near another Duke facility in South Carolina. “In light of the increasing number of recent reports of physical attacks on our nation’s infrastructure, it is important that we fully and clearly review the effectiveness of our existing physical security standard to determine whether additional improvements are necessary to safeguard the bulk power system,″ Glick said.Įven as power was restored, Duke Energy Corp., which owns the two North Carolina substations, reported gunfire Dec. “The security and reliability of the nation’s electric grid is one of FERC’s top priorities,” FERC Chairman Richard Glick said at a commission meeting Thursday. The order by the Federal Energy Regulatory Commission directs officials to study the effectiveness of existing reliability standards for the physical security of the nation’s power grid and determine whether they need to be improved. WASHINGTON (AP) - Federal regulators on Thursday ordered a review of security standards at the nation’s far-flung electricity transmission network, following shootings at two electric substations in North Carolina that damaged equipment and caused more than 45,000 customers to lose power.
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