Answer / amir

step voltage is the voltage between your legs in
calculation of earthing system.

Answer / rod

If a high voltage source strikes the ground the voltage is
disenpated though the ground in widening circles until it
is reduced to zero, if a person was standing near the
centre of the discharge there would be a voltage difference
between 2 points the closer to the discharge point the
higher the voltage, as an example cows have been killed
when they are close to a lightning strike but not hit by
the lightning, this is due to the voltage difference
between their legs, ie step voltage

Answer / trevor

Think of a perfectly calm lake or pond, not a ripple in it.
Then you throw a large rock out into it. Ripples start from
that point and disperse 360 degrees outwards. The ripples
near the centre are higher and closer together than the
ripples further away from the point of impact, eventually
decreasing to no ripples at all as the surface tension of
the water takes over.
Now, in place of a lake or pond you have a field with a
high voltage(tension) power line in it; let's say 13,800
volts.
In place of the rock you have one of the high voltage lines
from the power pole that dropped into the field and is
making contact with the ground.
As the energy leaves the line and enters the ground, it
disperses outwards 360 degrees, gradually being absorbed by
the earth (or meeting enough resistance from the earth to
negate the energy) Unlike a pond, however, the energy
doesn't disperse evenly as different types of soil provide
less or more resistance than others.
As in the pond, the voltage that is nearer the point of
impact is higher than the voltage further out, i.e., 13,800
volts at impact, 9,000 volts a metre away, 6,000 volts a
metre from that and so on.
The concern is this; if you started walking towards the
downed line (at around one metre per step) from let's say a
hundred metres away, at first you'd be walking on ground
that has no voltage present. As you got closer the voltage
between your forward leg and back leg would be 100 volts.
Next step, 400 volts, then 1,000 volts. At some point
closer to the centre, you would take a step that is of a
high enough voltage (difference in potential between your
front and back foot) to either go through the footwear you
have on or jump over your footwear and go directly into
your legs. You are then creating a pathway for the voltage
to travel in and would have all of that voltage and
ampacity go through you.

Answer / hajhooj

when hv strikes ground it creat a voltage on the ground
mass around the point of the strike.this voltage is fading
as the point goes further from the point of strike.voltage
level at equal distance from the the center is equal.now
the step voltage is the difference in voltage between two
point which are located one meter apart from each other on
one line that is coming from the point of strike.

Answer / k.prakashchandra

If a phase wire falls on the ground ,if you stand almost on
the line between the neutral grounding point and fault point
you receive the maximum step voltage, if your are feet are
apart along this line.The intensity increases if the fault
is at a short distance from the neutral grounding and you
get a heavy jolt depending on the phase voltage.The step
voltage is equal to phase voltage x distance between your
feet / the distance between fault and neutral ground.
Luckily ,line trips almost instantly.

Answer / abdul

correct term is "Step potential"
It is voltage formed between legs when walking in a high
voltage area ie a substation. we have to make small steps
while walking in such substation yard. Lambs and small cows
usually kills when thy jumb.

Another term is "Touch potential"
This is also dangeorous. to reduse the risk, all substation
yards filled with stone metals.

Answer / benji

It is the voltage waveform that occurs when a switch is
turned on.

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