Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [spark]

117 questions
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Do you need high voltage or current to produce a spark?

An electric spark can be formed when there is high potential energy between two conductors, right? My question is can a spark be formed with high current and low voltage or only vice-versa?
JingleBells
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How far can mains voltage arc in air?

I wondered this while soldering a mains voltage circuit board and was surprised by how close together the traces were. It has obvious implications in design of electrical plugs, and the proximity of wires when doing anything to do with mains…
M_M
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Why is Ethernet not intrinsically safe?

I understand from a training session that ProfiBUS is considered intrinsically safe, while ProfiNET is not. Some googling indicates that ProfiNET can never be intrinsically safe, because Ethernet can not be. This surprises me, as Ethernet over fiber…
Stephen Collings
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Arduino resetting/hanging due to sparks in ac line

This is the PCB design of the project I have been working on recently (my first pcb design). The idea is to control ac appliances (fans, bulbs etc) without relays. I am using triacs which are better than relays for such applications. I am using…
Whiskeyjack
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Voltage required for a spark plug - dielectric constant of air

The dielectric constant of air is approximately 3 kV/mm. The typical space between car spark plugs is between 0.6 and 1.8 mm. By multiplying those numbers in mm by the dielectric constant of air, we figure that a spark plug would work for between…
William Garske
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Why did a spark occur between my HDMI cable and metal lamp base?

Edit: Update 1/2/22 @ 2:27 UTC: outlet tester shows that all outlets and power strip outlets being used were normal. Update 1/2/22 @ 21:07 UTC: performed various continuity tests which suggest to me that the monitor, HDMI cord, and PC are normal,…
dfncrbl
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In the recent Con-Ed transformer "fire", what exactly produced the color of the huge blue glow over New York City?

Blue is often linked with technology (e.g. "big blue", glowing pools of water with Cherenkov radiation, aliens in general, Nobel prizes for blue LEDs) as well as traditional things like sparks. In a huge transformer "fire" event like this, what…
uhoh
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Will a spark gap transmit a signal an FM receiver can "hear?"

Forgive me if this question is a duplicate, I looked around but did not see anything that quite fit. The scenario: I found a box of old FM receivers, the kinds used (I think) for assistive listening or something like it, from Williams Sound,…
Jesse
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I have 5 kV available to create a spark. Is limiting the current to 500 µA as simple as putting a 10 MΩ resistor in series?

Haven't worked with high voltage much before, I'm trying to use a spark gap to ionize some gas. I have 5 kV on one side, and a plate attached to ground on the other. The 5 kV will switch on as needed, but I want to make sure the current doesn't…
Shredder
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Detecting sparks at the output of a high voltage flyback transformer

I was trying to generate plasma inside a cylinder for a hobby project, so I decided to use a flyback transformer from an old TV and drive it with a 555 timer as shown in the schematics. It solves my problem and the plasma looks something like…
Kadyan
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Measuring current with a multimeter - What did I do wrong?

I wanted to measure the current of a generic lithium ion battery charger. I set I plug my red lead in the A 10A max fused and black into COM. The charger is rated at 600 mA and my other lead plug is fused to 250 mA so obviously that wouldn't…
TheMidnightNarwhal
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How can I prevent inrush current from causing sparks when I connect my project to a power source?

It is a common problem with my projects that when I plug connector in (DC connector to DC jack), sparks can be seen, although it hardly takes 10 watts of power. On commercial products, this is not a problem. For example, why doesn't my laptop…
Bhavya Gupta
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Sparks on grounded metal bodies on lighting strikes in the nearby (two miles)

I have a strange phenomenon in our mountain cabin, on the Italian alps: lightning strike on the nearby (not so near: < 2 miles) causes audible / visible sparks on: electric / fire wood water heater pipes (very frequently) LED spotlights…
SpecialFx
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Any tricks for finding the path taken by small ESD sparks across a PCB?

A small ESD spark is able to find its way across my PCB at a relatively low voltage (low kV). It is not obvious which path the spark is taking and the sparks only jump when the board is sealed up inside an assembly so it is not possible to visually…
bigjosh
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Ignition coil arc initiation with protected low voltage continuation?

I'd like to initiate a spark plug arc with an ignition coil and then power the resulting (highly conductive) plasma with an ultracapacitor (low voltage, say 12V to 24V, and high current) without damaging the ultracapacitor during the initiation. …
James Bowery
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