Why humming sound occur in extra high tension transmission lines?
The noise is better described as 'buzzing', rather than 'humming', and it is caused by the breakdown of the air's insulating properties, due to stress caused by electric fields set up in the vicinity of where the conductors are supported from insulators. The noise is accompanied by a pale blue discharge which becomes visible after dark.
2 people found this useful
YES BUT INSULATED CABLE ARE USED
There's an electronic control in the transmission, called a pressure control module, that could be out. Mine does the same thing every now and then, but corrects after a cool-…down and restart. If the problem doesn't go away on its own you'll have to have the tranny serviced. A new PCM is about $300 plus labor. I didn't do this myself, so I don't know how hard it is to get to.
Usually HV is 33KV and 66KV, EHV is 132KV, 220KV and 400KV and UHV is 800KV and 1200KV
To reduce the power losses or conduction losses in transmission lines. - Yes its right. I will give a slightly improved answer. The size of coper conductor used for tran…smission lines is inversely proportional to the square of voltage transmitted. Hence normally for long transmission lines the voltage is increased to a very high value so as to reduce the amount of copper conductor used, hence reduce losses. Answer For a given load, the higher the supply voltage the lower the load current. The primary reason for using high-voltage transmission lines is to reduce the otherwise enormous voltage drops that would take place along the lines. The secondary reasons are to enable the use of conductors of practical size, and to minimise line losses.
More than 11KV over head conductor called as High Tension .... Another Answer 'High tension' is an archaic term for 'high voltage'.
Whenever there's something vibrating, in the upper range of human hearing, there may be a high pitch sound.
Current flowing along the wire sets up a magnetic field. Thecurrent in the next wire, in the field of the first wire, causes aforce. The current changes direction, cycling 50 …or 60 times persecond, and that is the hum you hear - it's all the wires vibratingslightly.
the current causes alternating magnetic fields which shake the wires and they get warm so snow and rain sizzle off the wires.
I think you're confusing "tension" with "voltages". Current flowsin loops, so if there is no place for the current to "escape"between what you're referring to as the "high ten…sion line" and the"low tension line", then the current will be the same in both. Another Answer The two lines are independent of each other, so there is norelationship between their currents.
from what i can remember its so that less energy is wasted when the electricity travels through the national grid . the voltage is then decreased afterwards .
bulk oil circuit breaker
bulk oil circuit breakers
ya its very simple. Due to the high potential, there is a greater electric field developed around the conductors. This field ionizes the air present around the conductors. D…ue to the air to being ionized, the current wants to flow around it. So the sparking occurs. Which is actually the form of current.
expansion and contraction
I don't know LOL
It is necessary for transmitting power over long distances, becausethe use of a higher voltage enables the power loss in theresistance of the cables. A useful guide to the vol…tages used is 2 kV per kilometre.