To prevent the risk of out-of-phase supplies mixing, sections of line fed from different feeder stations must be kept strictly isolated. This is achieved by Neutral Sections (also known as Phase Breaks), usually provided at feeder stations and midway between them although, typically, only half are in use at any time, the others being provided to allow a feeder station to be shut down and power provided from adjacent feeder stations. Neutral Sections usually consist of an earthed section of wire which is separated from the live wires on either side by insulating material, typically ceramic beads, designed so that the pantograph will smoothly run from one section to the other. The earthed section prevents an arc being drawn from one live section to the other, as the voltage difference may be higher than the normal system voltage if the live sections are on different phases and the protective circuit breakers may not be able to safely interrupt the considerable current that would flow. To prevent the risk of an arc being drawn across from one section of wire to earth, when passing through the neutral section, the train must be coasting and the circuit breakers must be open. In many cases, this is done manually by the drivers. To help them, a warning board is provided just before both the neutral section and an advance warning some distance before. A further board is then provided after the neutral section to tell drivers to re-close the circuit breaker, although drivers must not do this until the rear pantograph has passed this board. In the UK, a system known as Automatic Power Control (APC) automatically opens and closes the circuit breaker, this being achieved by using sets of permanent magnets alongside the track communicating with a detector on the train. The only action needed by the driver is to shut off power and coast and therefore warning boards are still provided at and on the approach to neutral sections.
What was the main requirement for electric feeder stations?
line fed from different feeder stations must be kept strictly isolated

The company, which benefited from the imperial patronage, soon expanded its commercial trading operations, eclipsing the Portuguese Estado da India, which had established bases in Goa, Chittagong, and Bombay, which Portugal later ceded to England as part of the dowry of Catherine de Braganza. The East India Company also launched a joint attack with the Dutch United East India Company on Portuguese and Spanish ships off the coast of China, which helped secure their ports in China. The company established trading posts in Surat (1619), Madras (1639), Bombay (1668), and Calcutta (1690). By 1647, the company had 23 factories, each under the command of a factor or master merchant and governor if so chosen, and 90 employees in India. The major factories became the walled forts of Fort William in Bengal, Fort St George in Madras, and Bombay Castle.
who helped join the East India company in a joint attack on Portuguese and Spanish ships?
Dutch

The television industry developed in New York and is a significant employer in the city's economy. The three major American broadcast networks are all headquartered in New York: ABC, CBS, and NBC. Many cable networks are based in the city as well, including MTV, Fox News, HBO, Showtime, Bravo, Food Network, AMC, and Comedy Central. The City of New York operates a public broadcast service, NYCTV, that has produced several original Emmy Award-winning shows covering music and culture in city neighborhoods and city government.
What comedy channel on cable television is headquartered in New York?
Comedy Central