1000a?

[capwizard]

5000 Amp Fuse + Tools Melt With High Current
https://www.youtube.com/watch?v=DJOX0c60wQE

220v x 10a =2200w 2000w /2v=1000A?

[budm]

Re: 1000a?

"220v x 10a =2200w, 2000w/2v=1000A?" What's the question?

[capwizard]

Re: 1000a?

i don't think the variac transformer would last too long and the AC wires to Toroidal Transformer are so tiny. 3 turns of wires into toroidal transformer will give out roughly how much voltage and current ?

PS: Electric Man from UK

[budm]

Re: 1000a?

I think you need to look into the relationship between input/output power, and transformer.
http://www.amadamiyachi.com/servlet/...1530000000Jybm

[redwire]

Re: 1000a?

Who is dumb enough to short things on their Persian carpet? LOL

It is easy to make very high currents with a few turns on a transformer.
Microwave oven transformers output almost 1V/turn and for a 1,200VA transformer it can easily make 1,200A theoretical but I2R losses in the wires and connections give you less.

In the oilfield, they flash-butt weld sucker rod, about a 1" steel rod (20-30mm OD). It is done shorting a bank of car batteries on a truck.
They wanted to know if the weld was good or not. So I did math on the current waveform.
I measured currents of 10,000A for over 15 seconds. Open-circuit is 12V. Some trucks could make 12,000A DC.

[capwizard]

Re: 1000a?

"I measured currents of 10,000A " Oh! It almost likes A thunder.

What is the voltage and current at the time of thunderstorm?

1.The estimated peak power per lightning stroke is 10^12 watts (1,000,000,000,000 watts or 1,000 Giga Watts). The total energy in a large thunderstorm is thought to be enough to power the whole of the USA for 20 minutes.

2.A tall thunderstorm cloud can hold over a 100 million volts of potential. The voltage potential in a lightning bolt is proportional to its length, and varies depending on the diameter of the bolt, air density and impurities of the air (humidity, dust, ash). The electrical breakdown of air (ionization) normally take 3,000,000 volts per meter, however with the ambient electric fields of a charged thunder cloud and impurities in the air, ionization normally takes place at much lower voltages during a storm. Lab tests have shown a leader will advantage if the tip of the streamer is about 4.5kV (4500v) for a negative charge and 5.5kV (5500v) for a positive charge.

3.An average lightning strike discharges about 30,000 amperes (20,000 amperes in the UK). The current in a lightning strike typically ranges from 5,000 to 50,000 amperes depending on the strength of storm. NASA has recorded strikes of 100,000 amperes and there are other reports of strikes over 200,000 amperes.

4.The resistivity of clear, fair-weather air ranges from around 4 x 10^13 ohm meters at sea level, to around 1.3 x 10^16 at 12km elevation. Typically air is considered an electrical insulator, however with impurities (water, dust ash) its resistance is lowered and varies further. Unlike metals whose resistance increases with temperature, when the temperature of air increased it has similar characteristics to semiconductors in that its resistance lowers. So when air is ionised into a plasma state and then super-heated to 25000 degree Celsius it conducts electricity very well.

5.Lightning can and does strike the same place twice. On average lightning strikes the Empire State Building in New York City (USA) about 100 times every year. 49 strikes have been recorded in a single day.

6.Positive lightning from the top of storm clouds is normally over 6 times stronger than negative lightning due to the longer distances it typically has overcome. Sometimes referred to as “bolts from the blue” they can occur when there is very little cloud activity compared to the thunderstorms associated with negative lightning. The unexpectedness and the greater strength make positive lightning the most dangerous type of lightning. Positive lightning makes up less than 5% of all lightning strikes.

PS: Franklin flying a kite with a key in an electrical storm!................

[diif]

Re: 1000a?

PS: Franklin flying a kite with a key in an electrical storm!................

There is no proof this ever happened. He theorised and wrote about it. If it had happened as he wrote it, it would have killed him. As proved by Mythbusters.

Why is an average lightening strike 30,000 amps but only 20,000 in the UK ? What causes this difference ?

[capwizard]

Re: 1000a?

The lightning strike current discharges buy ocean? Too many lightning strikes it has no more power! I guess...

http://www.aharfield.co.uk/lightning...bout-lightning

Research by Nasa shows lightning is more likely to hit land than sea and that it is rare for strikes to occur in deep ocean areas. Waters just off coasts are more often affected.
Risks also vary according to seasons. "You expect more strikes nearer to land because that's where the most heat and updrafts and storms build up, especially in the summer," says Shonk. "That can change in winter, but that's obviously a time when there are fewer people in the sea."

The lightning current is likely to radiate across the surface. Various different estimates have been given for the distance over which it would dissipate to the point where it would not be a harmful to a person.