Generally, electric utilities may be liable for failing to insulate, warn about, properly maintain, de-energize, or place their wires.
|
|
"That system detects electrical faults and directs circuit breakers to isolate and de-energize those faults," the company said in a statement.
|
|
As a result, Walmart informed Tesla on May 31, 2018, of its intent to "de-energize" its roofs, or disconnect Tesla's systems.
|
|
However, PG&E said Thursday it didn't de-energize a 230,000-volt transmission line near Geyserville that malfunctioned minutes before the fire erupted.
|
|
Last week, Walmart slammed Tesla with a lawsuit claiming the , forcing the retailer to de-energize all 240 locations where panels had been installed.
|
|
It also adopted a more aggressive policy regarding when to de-energize its lines as a precaution in the event of high winds, she said.
|
|
The Arizona Public Service, a state electric company, said via Twitter that it was "coordinating with emergency personnel" and was ready to de-energize lines if needed.
|
|
Furthermore, local solar and batteries can help communities, particularly vulnerable populations, when utilities must de-energize power lines to avoid greater harm caused by natural disasters like wildfires.
|
|
CRC Press, 1998. Page 358. and either annunciate an alarm to notify the operator or automatically de-energize the motor when a faulty condition occurs. For overloaded conditions, motors are protected with thermal overload relays.
|
|
Bi-metal thermal overload protectors are embedded in the motor's windings and made from two dissimilar metals. They are designed such that the bimetallic strips will bend in opposite directions when a temperature set point is reached to open the control circuit and de-energize the motor. Heaters are external thermal overload protectors connected in series with the motor's windings and mounted in the motor contactor. Solder pot heaters melt in an overload condition, which cause the motor control circuit to de-energize the motor.
|
|
A pressure switch will energize the pump if hydraulic pressure falls below a preset level and de-energize the pump when pressure returns to normal. A duty cycle of 3 minutes on and a cooling period of 20 minutes off is required to avoid overheating the pump motor.
|
|
High voltage switchgear A section of a large switchgear panel. Tram switchgear This circuit breaker uses both SF6 and air as insulation. In an electric power system, switchgear is composed of electrical disconnect switches, fuses or circuit breakers used to control, protect and isolate electrical equipment. Switchgear is used both to de-energize equipment to allow work to be done and to clear faults downstream.
|
|
Diodes are frequently used to conduct damaging high voltages away from sensitive electronic devices. They are usually reverse-biased (non- conducting) under normal circumstances. When the voltage rises above the normal range, the diodes become forward-biased (conducting). For example, diodes are used in (stepper motor and H-bridge) motor controller and relay circuits to de-energize coils rapidly without the damaging voltage spikes that would otherwise occur.
|
|
Consider a relay that has to energize to show a green light. If a wire breaks, or the battery is drained, then the relay will de-energize and the signal will show a red light, which is fail-safe. If a stray wire from another circuit touches the wire connected to that same relay, then that would be a wrong side failure, which is potentially dangerous. This stray wire can be guarded against by ensuring that the insulation on the relay wire is of good quality, and that all terminals are locked away.
|
|
The tank of liquid filled transformers often has radiators through which the liquid coolant circulates by natural convection or fins. Some large transformers employ electric fans for forced-air cooling, pumps for forced-liquid cooling, or have heat exchangers for water-cooling. An oil-immersed transformer may be equipped with a Buchholz relay, which, depending on severity of gas accumulation due to internal arcing, is used to either alarm or de-energize the transformer. Oil- immersed transformer installations usually include fire protection measures such as walls, oil containment, and fire-suppression sprinkler systems.
|
|
Upon arrival and while eating breakfast, the first deckhand conducted a safety briefing, which was interrupted when a passenger fainted; after the passenger was revived, the captain continued the briefing. Conception then sailed to the eastern side of the island and anchored in Smuggler's Cove overnight. As part of their regular nighttime routine, the crew had an unwritten policy to shut down the circuit breakers to de-energize the galley burners and griddle. The excursion held a night dive at Quail Rock, on the northern coast near the western end of the island, from 8:30 p.m.
|
|
Depending on the sequence, the rotor may turn forwards or backwards, and it may change direction, stop, speed up or slow down arbitrarily at any time. Simple stepper motor drivers entirely energize or entirely de-energize the field windings, leading the rotor to "cog" to a limited number of positions; more sophisticated drivers can proportionally control the power to the field windings, allowing the rotors to position between the cog points and thereby rotate extremely smoothly. This mode of operation is often called microstepping. Computer controlled stepper motors are one of the most versatile forms of positioning systems, particularly when part of a digital servo-controlled system.
|
|
A video describing the dangers of arc flashes and measures that can be taken to reduce risk to workers There are many methods of protecting personnel from arc flash hazards. This can include personnel wearing arc flash personal protective equipment (PPE) or modifying the design and configuration of electrical equipment. The best way to remove the hazards of an arc flash is to de-energize electrical equipment when interacting with it, however de- energizing electrical equipment is in and of itself an arc flash hazard. In this case, one of the newest solutions is to allow the operator to stand far back from the electrical equipment by operating equipment remotely, this is called remote racking.
|
|
The current to the coil windings is provided by a high current, very low voltage DC power supply, since in steady state the only voltage across the magnet is due to the resistance of the feeder wires. Any change to the current through the magnet must be done very slowly, first because electrically the magnet is a large inductor and an abrupt current change will result in a large voltage spike across the windings, and more importantly because fast changes in current can cause eddy currents and mechanical stresses in the windings that can precipitate a quench (see below). So the power supply is usually microprocessor-controlled, programmed to accomplish current changes gradually, in gentle ramps. It usually takes several minutes to energize or de-energize a laboratory-sized magnet.
|
|
However, as the firefighting operation progressed, it became apparent that the refinery's sewage system was not up to the task of properly draining the foam, water and petroleum-naphtha product mixture that was accumulating on the ground along Avenue Y, between 4th Street and 5th Street to the east, running in front of the refinery's administration building. These drainage problems were further exacerbated by a decision by refinery personnel to shut off drainage pumps. These pumps were shut off as part of a decision to de-energize overhead power lines that ran adjacent to Tank 231 along 4th Street. As the liquid mixture continued to build up in Avenue Y, Engines 16 and 40 were sent to Avenue Y and 5th Street to draft from a sewer intake and pump the material to a diked area some distance away.
|
|
Citing the said ruling, the Makati RTC in October 2008 obliged the National Transmission Corporation (TransCo) to "de-energize" the Sucat–Paco–Araneta–Balintawak Transmission Line. TransCo vice president for operations Carlito Claudio warned in November 2008 that complete retirement of the transmission line could trigger "hours-long rotating blackouts, just like during the power crisis in the 1990s," that might adversely impact the country's leading economic hubs of Makati and Ortigas, and added the unfeasibility of building an alternate underground cable line that would cost billion. Former TransCo president Alan Ortiz noted the transmission line as a crucial line, and said claims of electromagnetic radiation associated with high-voltage transmission lines like this "have yet to be 100-percent scientifically established." TransCo submitted a motion to the Supreme Court asking that they be granted until January 31, 2009 to carry out activities and coordination works in alleviating the impact of the impending shutdown, but was refused and instead supported the Makati RTC's decision in shutting the transmission line down.
|
|