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.

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66 views

Where to salvage inductors?

I need a toroidal inductor for my ZVS flyback driver. The value should be between 47uH to 200uH. It should be able to handle 6A. Where can I salvage them from?
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3answers
84 views

NE555 Flyback Driver MOSFET failiure

simulate this circuit – Schematic created using CircuitLab I made this simple NE555 Flyback driver. I used a 9V Battery to power the NE555 and a 24V 6A power supply to power the flyback. ...
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50 views

How to get better output out of flyback driver?

simulate this circuit – Schematic created using CircuitLab I used this circuit to power my flyback... I used an MJE3055T Power NPN and 10kOhm pot. The flyback is FKD15A001. I used the ...
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2answers
68 views

Cheap high-voltage low-current source

I'm looking to make a high voltage supply for some geiger-mueller tubes (the ubiquitous sbm-20 russian surplus tubes that everyone uses). these don't require much current at all, so creating high ...
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1answer
64 views

IC555 flyback driver troubleshooting

I made a flyback driver which just uses an astable 555 circuit to drive the flyback. The 4 and the 8 pins were connected to the positive rail. 7 pin was connected to the positive rail via a 1K ...
2
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2answers
58 views

Switchgear vs. power distribution center (PDC) vs. motor control center (MCC) - what's the difference?

Here's what I've observed so far: All three contain circuit breakers. All three supply power to motors, although switchgear and PDC-fed motors are obviously higher-voltage, larger motors. ...
3
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3answers
257 views

Digital logic input with very wide input voltage range

We are developing an industrial controls product that will be used to monitor the presence or absence of voltage ranging from 5V to 480V. Since the unit will be generic and programmable, this input ...
2
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1answer
73 views

Disconnectors Symbol in Single Line Diagrams (SLD)

where should the moving part of a disconnector be located when breaking gets applied, on the energized side or on the disconnected side? Is there any standard?? Suppose a non ring, simple grid and ...
2
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2answers
65 views

Safety concerns using metal switches near 300V (low current) lines?

I am building a nixie tube clock whose power supply in the best (or worst) case scenario will put out ~300V. This is obviously quite hazardous if not handled correctly. I need to use at least 1 spdt ...
2
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1answer
56 views

How uniform fields obtained between a set of electrodes in High Voltage Engineering?

In high voltage engineering, sometimes we need uniform fields between a set of electrodes. Parallel plate electrodes are not solution for that because they are finite so they will have fringing ...
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2answers
115 views

Marx Generator or Voltage multiplier

I am building a coilgun and I have constructed a coil with several thousand turns, an ohm meter measures its resistance at 300 ohms, so I am having trouble powering it, I ran 240v through it and got ...
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0answers
60 views

MOT Power supply issues

I am working on a quad MOT (microwave oven transformer) tesla coil. We tore apart 5 microwaves and got some MOTs. We first tested each MOT individually. They did not seem to have any problems. We ...
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0answers
27 views

Interrupting Current Limit Contactor; Circuit Breaker interrupting current

I am developing a contactor, an electromagnetic contactor. Magnet coil pushes a moving contact to make or break with a fixed contact. Now the design guideline says that there is an interrupting ...
2
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1answer
107 views

How can I control high voltage signals? (1 to 15kV.)

I'm an embedded s/w guy, but I'm able to do low voltage circuits without too much trouble. So I will try to ask this question on high voltages! I've got a power supply running at 1 to 15kV. It runs ...
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2answers
201 views

How can a small device produce two million volts? [closed]

After reading a shopping magazine, one of its products featured a stun gun the size of a large wireless car door opener* with the ability to produce two million volts. How can a small device ...
5
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1answer
153 views

Why do ceramic insulators have a stacked disc structure?

I've seen these stacked-disc structures on high voltage power lines everywhere. I could not find any information regarding this particular shape, though. From what I've noticed, high voltage ...
3
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3answers
226 views

How is transition from three-phase distribution without neutral to three-phase consumption with neutral achieved?

A typical distribution grid supplies 6 or 10 kilovolts AC to a substation near the consumers. This is typically done with a three-phase line without neutral - just three wires going in parallel. Then ...
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2answers
164 views

Would the FCA47N60F work for a ZVS flyback driver?

I have built a few flyback drivers from 555 controlled to the ZVS. I always have one problem, the power transistors keep burning out. For the ZVS driver, I used the IRFP250 and Keep having the problem ...
2
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2answers
368 views

Charging a small 100uF 450V capacitor with a small battery?

How can I easily charge a 450V capacitor with a small battery such as a 1.5V or 9V while stepping the voltage up in between so as to provide a voltage near 450V for the capacitor? I'm looking to ...
2
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0answers
84 views

High voltage, high frequency, pulser

For a rather unusual application, I need to generate high voltage (>500V) pulses with a very short rise time (10-100ps). Is there something that can do this off-the-shelf? Assume money is no object. ...
3
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2answers
169 views

Why would high-voltage cables have semiconductive layers in their design?

Turns out a high voltage cable can have semiconductive layers in its design. For example here's a rather old patent covering some specific way of producing such cable. This doesn't make much sense. ...
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2answers
89 views

What kind of cable can be used to power a mobile electric machine running of 6 kV AC?

I'm looking into the specifications of Hitachi hydraulic excavator model EX8000E-6 with electric motor. The spec says the motors are of type HITACHI TFOA-KK and run off AC 6 000 - 6 600 V / 50 Hz, ...
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3answers
75 views

Voltage Multiplier from Flash Camera Components [closed]

I have a bunch of Flash Camera capacitors and charging boards. I'm hoping to make some fun little projects with them. I couldn't figure out how to run a CRT flyback after getting it out of the tv so ...
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4answers
1k views

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 ...
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2answers
295 views

High Voltage input and output microcontroller

I am new to this, but I am looking to regulate a few ballast controlled fluorescent lamps with a micro-controller. Everything I look at has a low operating voltage and below 10 volt input/output ...
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2answers
157 views

How much current can these diodes handle in real world?

I came across these diodes on ebay today and was very surprised! So surprised that I probably have read something wrong. So I'm asking you guys just to make sure. Can these little guys literally ...
0
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2answers
121 views

Slowly supplying power to a very high load

Is it possible to supply power to a very high load within a huge time range? This question particularly regards MOSFETs. I know that a MOSFET must switch fast so that a little power would develop ...
2
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2answers
110 views

Does a conductor that is heavily negatively charged affect the number of free electrons or conductivity?

If a conductor is charged with several megavolts of static electricity, does it have a larger number of free electrons? If so, wouldn't they render the conductor more conductive? To truly test the ...
2
votes
1answer
95 views

Preventing Arc Discharge

I am repairing some ozone generators and one of them has a tower with a discharge path I can't seem to get rid of. Back in the heyday of television, my dad ran a side (hobby) business repairing bw ...
4
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1answer
173 views

MOSFET based switch for high voltages

I'm struggling with the design of a MOSFET based switch for high input voltages. See schematic of the basic circuit that I've come up with: simulate this circuit – Schematic created using ...
7
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2answers
341 views

Feeding a Full-Bridge from a Boost Converter?

I have been researching about designing a 3kW DC-DC Converter (Vin 12V from a battery, Vout 350VDC) and actually wired up a simple isolated Full-Bridge based DC-DC converter a few days back converting ...
1
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2answers
291 views

Advice on safe discharge circuit for HV Capacitors (400v)

In designing a relatively high voltage DC-DC converter, my output capacitor happens to be a 100uF electrolytic charged to 400v nominal. Efficiency is a design constraint, so I would like to know of ...
1
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1answer
128 views

Troubleshooting ZVS flyback failure

I built a ZVS flyback driver a couple months ago, and it worked great and amazed people with the arcs it managed to create. I used 2 IRFP250 MOSFETS and the results were great. One day I was wanting ...
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2answers
137 views

Most compact high voltage source for making long arcs

Out of curiosity, I have a question about high voltage electricity sources. Hypothetically, the requirements are that the source must be no larger than a water bottle (although smaller is better), and ...
1
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1answer
157 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
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2answers
53 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 ...
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4answers
620 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
195 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 ...
4
votes
2answers
784 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 ...
1
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2answers
210 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
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1answer
394 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
471 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
132 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)?
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3answers
2k 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 ...
10
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2answers
937 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? ...
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2answers
161 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 ...
7
votes
1answer
451 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 ...
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2answers
579 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
455 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
107 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 ...