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.
1
vote
1answer
79 views
How to create high voltage dividers without blowing up resistors
I figured out that it took around 75 volts to light up a neon bulb I had. I want to make a high-voltage meter with a few bulbs specifying certain amount of volts. So as a first test, I just hooked up ...
0
votes
2answers
30 views
Sharing the low voltage rail of unknown potentials… How to make Proper Floated Voltages?
I asked a previous question about running circuitry off a high voltage supply with unknown ground potential. The question is here: Generating a 10 volt rail from a High Voltage Supply with unknown ...
0
votes
4answers
75 views
Using an Opto-Isolator to detect 120VAC on a Microcontroller
I am designing a system where I need to know whether or not 120VAC is present on a specific wire.
The system is in line with a fuel pump system, and I need to check to see whether or not the pump is ...
4
votes
2answers
96 views
When is it appropriate to galvanically isolate components/subsytems?
As the question implies, how do you determine when it is appropriate to galvanically isolate parts of the same electrical system from one another?
For example, I'm currently constructing a tube ...
3
votes
2answers
98 views
Guessing power line voltage from the number of disc insulator
Is there a good way to guess the power line voltage based on the number of insulator discs that attach the line to the transmission tower?
Wikipedia seems to suggest that there is a "Typical number ...
0
votes
2answers
136 views
Is it possible to provide power using (effectively) a single wire?
I come to this question after a few thoughts on capacitors.
A capacitor essentially transfers (and stores) energy using an electric field through an insulator. The plates of a capacitor are not ...
0
votes
1answer
71 views
How to reduce VOC of solar panels to match the MPPT
My panels have VOC of 36VDC.
I like to connect 5 panels in series. But in such case the total VOC would be as high as 180V, and damage my Charge Controller.
Is there any dummy load, or shunt kind of ...
2
votes
3answers
111 views
Three Phase Input to Single Phase Output
We have three phase input and the voltages in the three input is not the same always. Sometimes, one or two or three phase will be off. I would like to connect the phase to output which lies within ...
3
votes
3answers
64 views
High voltage meter
I am working with high voltage arcs a lot but I have no way to measure the voltage. What is a good way to measure very high voltages (up to tens of thousands)?
4
votes
3answers
223 views
DC-DC converter, 12V to 400V? Is this possible?
To be able to charge a high voltage battery (~400V) from solar panels I need a dc-dc converter that can boost up the voltage from the low voltage system (~12V) to the higher voltage.
The power needed ...
-3
votes
0answers
46 views
ionization using electric field [closed]
Anybody who has this idea,thanks friends;
can the electrical resistance of copper limit the threshold value of ion generated from a sharp edged copper wire? for example with applied voltage increment ...
10
votes
2answers
662 views
The electricity grid: what keeps small power generators from being 'driven' by large ones?
This is a two part question and pertains to power generation:
What prevents a larger plant (say nuclear) from turning an itsy-bitsy gas generator into an electric motor and drive current through it? ...
1
vote
2answers
82 views
Measuring large differential voltage
I have a high voltage power supply for an electron beam system. The voltage regulator is an old analog system that works via a simple comparator and reference signal from a POT. My problem is the ...
0
votes
0answers
100 views
Is it safe to use a Relay to control my room lights with a microcontroller?
Firstly, I would just like to state that I'm a complete n00b to electrical engineering.
I'm thinking of controlling my room lights with a microcontroller.
The way I'm planning to do it is by placing ...
7
votes
1answer
171 views
Understanding a high voltage generator circuit
I found a thread in the forum about a high voltage power supply 3V to 500V DC converter and someone suggested a circuit from techlib H.V. generator for Geiger tubes:
However,when I tried to ...
4
votes
2answers
148 views
Have I fried my Arduino UNO?
So I've recently been playing with my first Arduino, until it, for some weird reason, stopped working.
What I did:
I had it attached to a breadboard. When I say attached, I mean it was supplying ...
4
votes
3answers
199 views
3.3V DAC output to 50V amplification
I have DAC 3.3V generated narrow square pulses that I need to amplify to 50Vdc. For this purpose an OPA551 single supply opamp works fine, but it's quiescent current of ~7mA @ 50V consumes too much ...
2
votes
1answer
99 views
How do plasma flames work?
I am used to arcs, where the electricity wants to go to ground, or negative, but here, I saw the electricity going up into the air just like a flame from a candle. How does this work and how can this ...
3
votes
2answers
149 views
What is the output voltage of this 555 timer high voltage circuit?
I'm trying to calculate the theoritical output voltage of the following 555 timer high voltage circuit.
It claims to output up to ...
0
votes
0answers
74 views
Help on a 5000w mercury arc ballast
Not sure where to begin as I don't think I even understand the operation. First I know there's a transformer then I guess there's an inductor on the side of the lamp that acts as a current limiter ...
3
votes
3answers
278 views
Simulation for a transmission loop using PowerWorld
I am now learning how to use PowerWorld Simulator. However, I faced some problems when I tried to enter the data given in the paper.
I want to simulate the following transmission loop:
First things ...
2
votes
2answers
161 views
2kV capacitor on ethernet?
I'm building the circuit of this article:
C7 is rated 1nF 2kV. Is this right, does this capacitor need to be able to handle 2kiloVolt? Why is that? Is ethernet dangerous?
6
votes
4answers
352 views
+50
Charging a circuit to around 10kV from 3V (two AA batteries) for discharge over 20msec
How can I design a circuit that can be charged to around 10kV (somewhere between 5 and 20kV is fine) from two AA batteries (~3V)?
I am going to draw about 20mA over a high resistance load for a short ...
2
votes
1answer
392 views
22J 6KV and 33J 6KV are two kinds of ceramic cap that seems to be burned out. What do I replace it with?
These capacitors are located in power supply module DPS-279BPA section where it is marked with high voltage area. It is a Phillips LCD television...
2
votes
1answer
180 views
Why does my PSU die everytime I test with multimeter
I've set up my PSU to use as a "lab power supply", I'm trying to obtain 12 Volts at 14 amps. I have the red, orange, yellow, black wires separated, and connected the green wire to ground to keep the ...
3
votes
1answer
148 views
Why does this insulator separate two conductors with equal voltages?
Here goes a view-from-below picture of a 3 kilovolts DC railway catenary
Here B is a suspension cable, C is a two-stranded contact wire - one which the train pantograph touches. Between B and C ...
0
votes
3answers
151 views
Can I use a standard SMA connector and cable to deliver high voltage to a PCB?
I'm designing a power circuit which I need to bring high voltage, ~3000V DC, into from an external power supply. Normally I would use an SHV connector, but they don't seem to offer these connectors in ...
3
votes
2answers
189 views
Measure current in high voltage (10kV)
In a plasma application (Helium or Argon Plasma), we would like to measure the current. The voltage is around 10kV AC and modulated with a function generator.
Currently we only have one of those ...
3
votes
2answers
123 views
Electrostatic painting on plastic
I'm attempting to create an electrostatic painting process for small plastic parts. The material is ABS and is about 4 inches by 6 inches by 1 inch high. I'm somewhat familiar with electrostatic ...
0
votes
0answers
72 views
Electrostatic Dust-Repellant For Painting
I paint small, ABS plastic parts that are very high gloss and am having a problem with dust particles and lint embedding in the wet paint while it is being sprayed. The level of gloss causes these ...
0
votes
2answers
124 views
Low Frequency, High Voltage Oscillator
I am trying to create a speed control for a brushless AC motor, like those used in fountain water pumps. Since the speed of the motor is determined by the line frequency I want to make a low ...
2
votes
1answer
230 views
Why high voltage from TV flyback shocks you without the need to complete a circuit?
Assuming the TV is plugged into an isolation transformer (although I think there is already a small transformer onboard), then ground is not part of the secondary side. Yet, high voltage from flyback ...
4
votes
1answer
281 views
Inductive “kick” and possible dangerous experiment
So I have this unmarked, unknown transformer (probably from a microwave oven so it is pretty beefy) and I thought that a safe way to determine the primary from the secondary windings would be to put 1 ...
3
votes
2answers
184 views
Is it possible to switch relay above the power spec?
I am planning to use a DC drived SPST reed relay. Below I include the spec for voltage, current and power ratings.
Contact Rating: 200W
Carry Current: 5A
Switching Current: 3A
Switching Voltage: ...
2
votes
2answers
214 views
HV DC power supply
I want to build a HV DC power supply for a tube amp ( 1.2 kV at about 500 mA).
I intend to make it light using multiple voltage multiplier stages and no transformer...
Having no transformer I am ...
1
vote
1answer
132 views
Light switch setup for bedroom [closed]
on my bedroom I want to put two 220V lights on the side of my bed, and I want to control them with 3 switches:
the main switch is beside the door, and will commute both lights on and off.
two ...
14
votes
3answers
544 views
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, ...
8
votes
6answers
3k views
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 ...
7
votes
1answer
259 views
What is residual power?
In a television show, high voltage power company workers were helping an animal to safety which climbed up a tower carrying high voltage power lines. The commentator said that though the power was ...
6
votes
1answer
379 views
Simulating an automotive load dump with a bank of charged capacitors?
I've been working on a data logging device that will eventually go into my personal vehicle. I've scoured the interwebs and built what, in theory, should be a fairly stout power supply capable to ...
-3
votes
4answers
303 views
How can I repair my old tube TV safely?
I got an old Nokia tube television from my grandmother. I tested it, but there is no picture. I can hear the audio. The filament is not glowing. I am studying EE, but there I only dealt with low ...
7
votes
1answer
335 views
Power Line Crackle
I walk to work every morning and pass under some HV power lines. On high-humidity days, there's an audible crackle/sizzle emanating from the lines. I never hear this on the way home.
I would ...
4
votes
3answers
418 views
How is oil-filled switchgear possible?
I can't find any definitive description of how oil-filled switchgear uses the oil and manages to keep it from ignition and boiling. For example, the Wikipedia article says
Oil circuit breakers ...
6
votes
1answer
181 views
What is the most common type of high voltage cables?
I'm building the model of an admittance matrix for the German Grid, most specifically the Transmission grid. I only have characteristics of cables as number of cables, wires and voltage (I'm working ...
1
vote
1answer
111 views
How to wire AC power to an integrated DPST switch?
I have an IEC C14 power connector (like those on PC power supplies). The connector has an integrated DPST switch, however the power pins are not connected directly to the switch-- I have to do that ...
0
votes
2answers
271 views
Sixteen 100v isolated power supplies
I need to create sixteen isolated power supplies on a single PCB.
Input voltage 9v DC.
Output voltage 100v DC.
Output current 10mA each.
No precise regulation needed.
Efficiency not terribly ...
3
votes
1answer
348 views
Safety precautions working with high voltages (Nixie Clock)
I'm building a nixie clock kit with these instructions. I'm up to the part where I have to test (page 17) the high voltage components (the power supply is 12V 250 mA) which is up to 170 volts (page ...
4
votes
1answer
474 views
Buying a tesla coil?
I make music with an Arduino and old floppy drives and I also saw people making music with tesla coils. I've seen tesla coils for sale for about 200$ which seemed good, but there are some doubts:
...
4
votes
3answers
251 views
Is it technically possible to divert a lightning into a moving vehicle as in “Back to the Future” movie?
In "Back to the Future" movie the characters try to power the time machine installed into a car by diverting a lighting.
They know that a lightning should strike the clock installed on a specific ...
19
votes
3answers
2k views
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 ...
