Questions related to the design of circuits that supply or use a high voltage. There are a few definitions but the IEC definition of a high-voltage supply system is above 1000 Vrms AC or 1500 V DC.
Questions tagged [high-voltage]
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What are these boxes mounted inline on each of the 3 phase wires of a high voltage power line in Miami?
They were only on this run and not any of the lines in the area. And what is the function of the flat u-shaped guards in front of each?
bigjosh
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Is this video fake? I thought Tesla coils only worked on AC
This video shows a 9-volt battery connected to a wire as a primary.
The first reason I think this is fake is that he is powering a Tesla coil with 10 volts.
The second reason is that Tesla coils work on AC, or at least I thought so, and he wouldn't…
Gabriel ashmore
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Why am I not dead after repeatedly touching a high-voltage source?
While playing with mosquito racket in my home, I unscrewed the racket and touched the 2 wires with my hands. I felt that my bones were dislocated, I got shocked, but I am not dead.
My calculations say that I should die:
the output voltage is 5 kV to…
pankaj prasad
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Creepage distance for PCBs handling line voltage AC?
What is the required creepage (e.g. trace-to-trace) distance for PCBs handling 240VAC rms? What about 120VAC?
This is for UL and CE certification.
The standards for PCB Creepage (e.g. the distance across the surface of a PCB between high-voltage…
Connor Wolf
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How do transposition towers in transmission lines work?
There're such things as transposition towers in power distribution powerlines. The idea is that for example you have three conductors running in parallel at the same height and the leftmost of them is phase A and after transposition the middle one…
sharptooth
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Why are the high voltage overhead power lines with the same potential being isolated?
Photo #1
Photo #2
Photo #3 - A zoom of Photo #1
Photo #4 - A zoom of Photo #2
I shot these photos while travelling in a highway. In each line-group has three separate lines. I think that the three lines in each group carry the same electrical…
hkBattousai
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Can a high voltage line kill a person without touching it?
It's common (for me) to hear that a HV power line can kill a person without touching it "if they entered its field." I'm not convinced by this reason and I think it quite naive and that it doesn't clarify anything.
Warning: Video shows people…
iMohaned
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Why the arc when bonding-on during high voltage repairs?
When working on high voltage power-lines via helicopter the technician will "bond-on" with a steel wand called a hot-stick. During this process an arc is conducted from the line to the wand. Now, since the helicopter is floating both literally and…
Salbando Jones
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How can a high-voltage transistor be in such small packaging?
For example:
STN0214 - Very high voltage NPN power transistor
It is said to accept more than 1 kV between its collector and emitter. It comes in a SOT-223 package (3 pins plus a tab). With a dielectric strength of 1 kV/mm for humid air, cannot an…
julienfr112
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Why are consumers located near high-voltage lines typically not connected to those lines but instead are connected through a lower high-voltage line?
A typical grid uses 110..500 kilovolts lines to deliver electricity to substations which lower that to 6..20 kilovolts and then lines with that lower voltage get to consumers where yet other substations are located which finally lower those 6-20…
sharptooth
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Why do high voltage power lines hiss when it's raining?
I noticed when walking home the other day that the high voltage (200kv I believe) lines running through here were hissing in the rain. What is causing them to hiss?
pfyon
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Circuit for measuring high voltage DC voltage (up to 1000V)
I am a final year E&E student and I am trying to built a power meter that must be able to measure quite high DC voltages, up to 1000 V DC. I am measuring with a simple 12-bit ADC that has an input voltage range of 0 - 2.5 V. Would a simple voltage…
Eduan Shuda
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How to read high voltages on microcontroller?
I want to read high voltages, like ~50V, using a microcontroller. I plan to put this as an input into the microcontroller's A/D line. But of course, you shouldn't have voltage that high on the input of a microcontroller or it'll fry.
How might I…
Jack
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How does this mosquito zapper circuit work?
For the purpose of learning, I have tear down a small mosquito zapper racket.
I am now trying to understand how the circuit is working (which goal is to produce high voltage).
(yellow = resistor, black = transistor, red = led, gray = diode, blue…
tigrou
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How can a faulty USB charger kill you?
This question relates to this incident here, where a women in Australia died from a faulty USB charger that allowed the full 240V mains voltage through the USB cable.
Now from my understanding you would have to be connected to the mains ground or…
timonsku
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