for 415V phase to earth min clearance is 25mm pallav
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You cannot have a voltage between a 'phase' and earth. You should be asking the clearance between a 'line' and earth.
In 32 years of commercial electrical work, I have never seen a clearance specification for phases in a 480V, high volt panel. I have never seen it adressed in the N.E.C. (electrical code). Main lug clearance is typically 3 to 6 inches depending on size (amp rating) of the panel. Some manufacturers install a dialectric material (insulator) between main phase lugs allowing closer clearance. Underwriters Labratories which approves and tests all electrical equipment sold in the U.S. may have specs for clearance. Note that the clearance between breaker busses of different phases in 480V panels is often only a few inches. Again here, many maufacturers install a dialecric shield between buss phases.
Phase to phase clearance is the distance between phase conductors a person must stay. If someone is working on one phase conductor, they cannot get closer than the phase to phase clearance to another phase conductor.
AnswerThere is no such thing as a 'phase conductor', so you are actually referring to 'line' conductors. The spacing between line conductors of separate circuits depend on the operating voltages of the two circuits, so there is no one simple answer. These distances will be laid out in the utility company's standards manual based on national electrical standards.
A clearance is defined as shortest distance through the air between two conductive elements.
Practically all generators and many motors and high-power motors have 3 power conductors: the 3 phase wires.
Many also have a 4th "ground" or "earth" wire.
It is important to keep the physical distance (typically measured in inches or mm) between any one phase conductors and any other phase conductor, and between any one phase conductor and anything else (such as the earth conductor) big enough so that
(a) the normal voltage between the conductors should not cause a spark to arc between them, and
(b) the common surges of voltage caused by distant lightning strikes should not cause a spark to arc between them.
Many systems deliberately put the ground conductor relatively close to each phase conductor through a glow-discharge tube or other lightning arrester, such that
(c) the surge of voltage on a phase conductor, caused by nearer lightning strikes, causes an arc to the safety ground through the arrestoer and dissipates most of the energy relatively harmlessly.
See the related links for some information on how big those clearances should be.
phase to phase implies: voltage measuring between two lines at different voltages
while latter implies:" b/n one line to ground at zero potential"
The minimum separation for a voltage of 34.5kV and conductor spans of 50 meters or less is 600 mm. For countries that never changed to the metric system 50 meters is about 150 feet and 600 mm is about 24 inches.
The spacial distance between line legs increases as the line voltage increases. This also holds true from line voltage to ground. So as no voltage was stated then no correct answer can be given.
As for as I know, the clearance is based on voltage. For 415V AC the minimum clearance required between phases as per standard is 19.5mm.
140mm phase to phase 120mm phase to earth
255mm phase to phase 140mm phase to earth
space
120
If the Moon is between Earth and the Sun, it is not a phase, at all . . . it is a solar eclipse.
New moon.
Full Moon.
When the moon is positioned between the Earth and the sun.
When Venus goes behind the Sun (as viewed from Earth), its phase is full. You can't see it, of course. When it transits the Sun (passes between the Sun and the Earth), it's in its dark phase.
When dealing with a 3 phase power supply the safe clearance zone between each phase is usually within an arms reach, there are exceptions to this rule like a 3 phase socket or a distribution board.
If the Moon is between Earth and the Sun, it is not a phase, at all . . . it is a solar eclipse.
Your question should read, 'How much clearance is needed between LINES.... (not 'phases')?' The answer will depend on local authority regulations. The clearances in air tolerated by REC companies in the UK is 90 mm line to line and 127mm phase to earth. Even though there is a greater potential difference between line to line, the gap is less. I think it's to do with public safety if it flashes to earth.
Phase to phase clearance should be around 11.5 inches.
The clearance between 33-kV line (not 'phase'!) conductors depends on whether they are rigid (e.g. busbars) or can move (e.g. overhead lines); whether they are insulated or in air; etc.. So there are several 'clearance' distances. All are published on the internet -so you can do a search to find out for yourself.
1.2 meter
The phase of the moon depends on it position in relation to the earth and the sun. For instance, when the moon is in between the earth and the sun, this is the new of full moon phase.
full moon
an eclipse not an ellipse
new moon
New moon.
Depends on country.