Author Topic: HV phenomena  (Read 608 times)

Offline Andy Kay

  • High Voltage Enthusiast
  • *
  • Posts: 15
  • Karma: +0/-0
    • View Profile
HV phenomena
« on: May 05, 2018, 09:03:32 PM »
Whilst playing around with HV I've noted three different kinds of phenomena:

1. The basic spark.. small lightning strike and accompanying sharp crack
2. Beautiful violet arc that may be silent and may hiss
3. Cream-coloured arc that looks more like a flame and sounds more like a hum or buzz

Can anyone enlighten me as to the physics of these phenomena -- i.e. what is happening at the molecular level? I'd like to know what to expect under what conditions.

Thanks for reading.

Offline StaticBuildup

  • High Voltage Enthusiast
  • *
  • Posts: 4
  • Karma: +0/-0
    • View Profile
Re: HV phenomena
« Reply #1 on: May 06, 2018, 01:38:34 AM »
I have noticed this too and it appears to be down to voltage, current and frequency.

Type 1 is usually a discharge of static electricity, or a low frequency spark which is essentially a series of very short discharges.
(Van de Graaff generator, Wimshurst machine, some induction coils)

Type 2 is a DC or high frequency AC arc. From what I have observed, the thin arc and violet colour are associated with low current.
(CRT flyback transformer, ioniser, plasma ball)

Type 3 is a low frequency AC arc with high current. The flame appearance is because the heat caused by the high current pulls it up into a flame shape. The hum or buzz is the 50Hz or 60Hz frequency of the mains.
(Neon sign transformer, microwave oven transformer)

Offline Andy Kay

  • High Voltage Enthusiast
  • *
  • Posts: 15
  • Karma: +0/-0
    • View Profile
Re: HV phenomena
« Reply #2 on: May 06, 2018, 07:10:26 PM »
I have noticed this too and it appears to be down to voltage, current and frequency.

Type 1 is usually a discharge of static electricity, or a low frequency spark which is essentially a series of very short discharges.
(Van de Graaff generator, Wimshurst machine, some induction coils)

Type 2 is a DC or high frequency AC arc. From what I have observed, the thin arc and violet colour are associated with low current.
(CRT flyback transformer, ioniser, plasma ball)

Type 3 is a low frequency AC arc with high current. The flame appearance is because the heat caused by the high current pulls it up into a flame shape. The hum or buzz is the 50Hz or 60Hz frequency of the mains.
(Neon sign transformer, microwave oven transformer)
Thanks SB.
That would seem consistent with my experience... I get sparking from a ten-stage voltage multiplier but a violet plasma arc when current limited using ten 720k resistors in series, and I get the cream-coloured flame on a Jacob's Ladder driven by a flyback transformer (the driver draws around 5A). I was wondering what is happening to the air (oxygen and nitrogen molecules) to give these different phenomena.

Offline Uspring

  • High Voltage Experimenter
  • **
  • Posts: 77
  • Karma: +5/-0
    • View Profile
Re: HV phenomena
« Reply #3 on: May 07, 2018, 01:30:15 PM »
The different colors are due to the differing mechanisms which create the light. For high power arcs that is thermal radiation from the plasma. Typical temperatures are from around 4000K, which corresponds to a bright orange up to 10000K (white blueish) in an arc lamp. Often evaporating substances contribute to the color of the arc.

In low power discharges, e.g. corona or from power supplies with a low duty cycle or in low pressure, there is not enough power to heat up the gas significantly. The light comes from excited atoms or molecules, which were hit by high speed electrons causing the excitation. The color depends on the properties of the involved gas. It is often a line spectrum, which differs considerably from the smooth spectrum emitted from hot objects.

Offline Andy Kay

  • High Voltage Enthusiast
  • *
  • Posts: 15
  • Karma: +0/-0
    • View Profile
Re: HV phenomena
« Reply #4 on: May 07, 2018, 06:02:52 PM »
The different colors are due to the differing mechanisms which create the light. For high power arcs that is thermal radiation from the plasma. Typical temperatures are from around 4000K, which corresponds to a bright orange up to 10000K (white blueish) in an arc lamp. Often evaporating substances contribute to the color of the arc.

In low power discharges, e.g. corona or from power supplies with a low duty cycle or in low pressure, there is not enough power to heat up the gas significantly. The light comes from excited atoms or molecules, which were hit by high speed electrons causing the excitation. The color depends on the properties of the involved gas. It is often a line spectrum, which differs considerably from the smooth spectrum emitted from hot objects.
That makes sense. Violet arcs are cooler than whitish arcs then, which would be consistent with the Jacob's Ladder drawing 5A from a 15V supply and the voltage multiplier drawing 0.25A from a 13V lead-acid battery. Thank you.

High Voltage Forum

Re: HV phenomena
« Reply #4 on: May 07, 2018, 06:02:52 PM »

 


* Recent Topics and Posts

post Re: My First DRSSTC
[Dual Resonant Solid State Tesla coils]
sjsimmo
Today at 08:08:58 AM
post Re: How to calculate VA rating and other things for Ferrite Core? (SMPS)
[Transformer (ferrite core)]
sjsimmo
Today at 01:24:15 AM
post How to calculate VA rating and other things for Ferrite Core? (SMPS)
[Transformer (ferrite core)]
FilipŠebík
January 18, 2019, 07:32:38 PM
post Re: How to design a 7.5kV AC source?
[Transformer (ferrite core)]
profdc9
January 18, 2019, 04:25:14 PM
post How to design a 7.5kV AC source?
[Transformer (ferrite core)]
CristianM
January 18, 2019, 03:48:06 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
the_anomaly
January 17, 2019, 02:01:36 AM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
petespaco
January 16, 2019, 04:26:38 AM
post AC vs DC fuses, high current, explosive destructive testing and theory
[Capacitor banks]
Mads Barnkob
January 15, 2019, 09:48:48 PM
post Re: My X-Ray Machine
[X-ray]
neukyhm
January 15, 2019, 10:51:46 AM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
petespaco
January 14, 2019, 05:08:38 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
the_anomaly
January 14, 2019, 01:15:53 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
Mads Barnkob
January 14, 2019, 12:22:07 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
petespaco
January 11, 2019, 05:10:39 AM
post Re: My X-Ray Machine
[X-ray]
Max
January 10, 2019, 10:59:25 PM
post Re: 迎词、来
[General chatting]
profdc9
January 10, 2019, 06:56:59 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
petespaco
January 10, 2019, 05:33:48 PM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General chatting]
black.yang
January 10, 2019, 02:11:58 AM
post Re: My X-Ray Machine
[X-ray]
Mads Barnkob
January 09, 2019, 09:14:59 PM
post Acoustic spectra of sung vowels by the FFT analyzer HP 3561A
[Electronic circuits]
Physikfan
January 08, 2019, 08:44:16 PM
post Re: IGBT failure in DRSSTC
[Dual Resonant Solid State Tesla coils]
Felix Bieri
January 08, 2019, 05:33:55 PM
post Re: Huawei RRU3928 1800MHz radio base station teardown (part 1 of 2)
[Radio frequency]
Mads Barnkob
January 08, 2019, 08:25:08 AM
post Re: SimpleDriver v2.3, my phase-shifting QCW DRSSTC controller
[Dual Resonant Solid State Tesla coils]
flyglas
January 08, 2019, 08:25:02 AM
post Re: SimpleDriver v2.3, my phase-shifting QCW DRSSTC controller
[Dual Resonant Solid State Tesla coils]
Hydron
January 08, 2019, 02:01:50 AM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Hydron
January 07, 2019, 10:23:38 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Laci
January 07, 2019, 08:53:32 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
petespaco
January 07, 2019, 08:17:44 PM
post Re: SimpleDriver v2.3, my phase-shifting QCW DRSSTC controller
[Dual Resonant Solid State Tesla coils]
Netzpfuscher
January 07, 2019, 07:37:53 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Uspring
January 07, 2019, 01:30:36 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Laci
January 07, 2019, 12:43:26 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Hydron
January 07, 2019, 08:09:49 AM
post Re: SimpleDriver v2.3, my phase-shifting QCW DRSSTC controller
[Dual Resonant Solid State Tesla coils]
NEYi
January 07, 2019, 07:43:50 AM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General chatting]
Mads Barnkob
January 07, 2019, 06:48:06 AM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Mads Barnkob
January 07, 2019, 06:39:56 AM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Laci
January 06, 2019, 09:23:19 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
petespaco
January 06, 2019, 07:11:25 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Uspring
January 06, 2019, 07:02:14 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
flyglas
January 06, 2019, 12:43:46 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Laci
January 06, 2019, 11:55:09 AM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
TDAF
January 06, 2019, 09:48:06 AM
post Re: First SSTC build, need help troubleshooting
[Solid state Tesla coils]
TDAF
January 06, 2019, 09:45:17 AM
post 关于: 这个便宜的 drsstc 驱动程序从 aliexpress 1.3 b 类型?
[Dual Resonant Solid State Tesla coils]
black.yang
January 06, 2019, 08:34:46 AM
post 迎词、来
[General chatting]
black.yang
January 06, 2019, 08:20:21 AM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
flyrod
January 06, 2019, 12:34:15 AM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
petespaco
January 05, 2019, 05:27:23 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
flyrod
January 05, 2019, 03:46:29 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Laci
January 05, 2019, 09:51:10 AM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Mads Barnkob
January 04, 2019, 11:02:25 PM
post Re: (DR)SSTC II
[Dual Resonant Solid State Tesla coils]
Laci
January 03, 2019, 08:38:15 PM
post Re: SimpleDriver v2.3, my phase-shifting QCW DRSSTC controller
[Dual Resonant Solid State Tesla coils]
flyglas
January 03, 2019, 08:15:48 PM
post Re: Component questions
[Dual Resonant Solid State Tesla coils]
Mads Barnkob
January 03, 2019, 02:05:31 PM

Sitemap 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30