Author Topic: First revision  (Read 313 times)

Offline thedoc298

  • High Voltage Experimenter
  • **
  • Posts: 65
  • Karma: +0/-0
    • View Profile
First revision
« on: October 12, 2019, 12:26:44 AM »
https://drive.google.com/open?id=1sL2R1a7om4OT4U0Gt8UwrXXuiRFYxg8b

After some tips, made a change for the better. The cap cage is easy to pop apart and now can watch the caps.  Thanks for the help.
« Last Edit: October 31, 2019, 11:08:09 PM by thedoc298 »

Online MRMILSTAR

  • High Voltage Technician
  • ***
  • Posts: 114
  • Karma: +4/-0
  • Cedar Rapids, Iowa
    • View Profile
Re: so far video
« Reply #1 on: October 12, 2019, 02:38:43 AM »
It looks like things are progressing nicely. With 7200 volts from your pole transformer you will have to run some tight gap spacing on your RSG, probably no more than about 1 mm per gap but it is doable.

You may regret putting the capacitors inside that tube. Even though they do fit nicely, you can't see what's going on. You can't see if there is excessive corona, flash-over, blown capacitors, etc. I like to be able to observe everything in operation so that I can anticipate problems and to make everything easily serviceable.

Looking forward to see it in operation.
Steve White
Cedar Rapids, Iowa
Retired electrical engineer

Offline thedoc298

  • High Voltage Experimenter
  • **
  • Posts: 65
  • Karma: +0/-0
    • View Profile
Re: so far video
« Reply #2 on: October 12, 2019, 02:56:17 AM »
It looks like things are progressing nicely. With 7200 volts from your pole transformer you will have to run some tight gap spacing on your RSG, probably no more than about 1 mm per gap but it is doable.

You may regret putting the capacitors inside that tube. Even though they do fit nicely, you can't see what's going on. You can't see if there is excessive corona, flash-over, blown capacitors, etc. I like to be able to observe everything in operation so that I can anticipate problems and to make everything easily serviceable.

Looking forward to see it in operation.


Well now is the time for making the change, I have been thinking about a different setup for the cap anyway, something will pop up. The spark gap will be close because of the low voltage of 7200 is that correct...? Maybe just ought to junk it.  Got one more question what is you no load current draw on your transformer.

Offline thedoc298

  • High Voltage Experimenter
  • **
  • Posts: 65
  • Karma: +0/-0
    • View Profile
Re: so far video
« Reply #3 on: October 12, 2019, 02:58:19 AM »
It looks like things are progressing nicely. With 7200 volts from your pole transformer you will have to run some tight gap spacing on your RSG, probably no more than about 1 mm per gap but it is doable.

You may regret putting the capacitors inside that tube. Even though they do fit nicely, you can't see what's going on. You can't see if there is excessive corona, flash-over, blown capacitors, etc. I like to be able to observe everything in operation so that I can anticipate problems and to make everything easily serviceable.

Looking forward to see it in operation.


Got a idea to remove the center tub and repace with 4 pvc poles around the cap.

Well now is the time for making the change, I have been thinking about a different setup for the cap anyway, something will pop up. The spark gap will be close because of the low voltage of 7200 is that correct...? Maybe just ought to junk it.  Got one more question what is you no load current draw on your transformer.

The pig going to the back corner of the basment till a later time. Going to start the mod for the center support tomorrow, thanks much for the heads up.
« Last Edit: October 12, 2019, 03:48:07 AM by thedoc298 »

Online MRMILSTAR

  • High Voltage Technician
  • ***
  • Posts: 114
  • Karma: +4/-0
  • Cedar Rapids, Iowa
    • View Profile
Re: so far video
« Reply #4 on: October 12, 2019, 05:13:28 AM »
I think that you can make 7.2 KV work, its just that your gap spacing will have to be about 1 mm using 3 KV/mm as a rule of thumb. Remember that 7.2 KV RMS is 10.18 KV peak so your gap spacing is not quite as critical as first appears. Each of my gaps is about 1 mm even though I could get away with more since I am operating with 14.4 KV RMS. Its best to get the gaps as close as you can for the most reliable firing anyway. Some people have made 4 MOTs in series work and that is only about 8 KV RMS. I would try the 7.2 KV pole pig. No harm in trying.  If you find another 7.2 KV pig, you can put them in series.  :D I have seen that done.

One more thing to mention is that a higher voltage transformer is also better because of

E=0.5*C*(V**2)

where the capacitor energy, which also determines spark length, is proportional to the square of the voltage. The more charge you can put on that capacitor, within its safety limits, the better for discharge length.

I've never checked the no-load current on my pole transformer. There is usually a spec on this if you can find it or probably easier just to measure it yourself.

You may want to look at lots of pictures of how others have implemented their coils. It may give you some ideas. I looked at lots of pictures of coils before I built mine.
« Last Edit: October 12, 2019, 04:40:29 PM by MRMILSTAR »
Steve White
Cedar Rapids, Iowa
Retired electrical engineer

Offline thedoc298

  • High Voltage Experimenter
  • **
  • Posts: 65
  • Karma: +0/-0
    • View Profile
Re: so far video
« Reply #5 on: October 12, 2019, 05:28:01 PM »
I think that you can make 7.2 KV work, its just that your gap spacing will have to be about 1 mm using 3 KV/mm as a rule of thumb. Remember that 7.2 KV RMS is 10.18 KV peak so your gap spacing is not quite as critical as first appears. Each of my gaps is about 1 mm even though I could get away with more since I am operating with 14.4 KV RMS. Its best to get the gaps as close as you can for the most reliable firing anyway. Some people have made 4 MOTs in series work and that is only about 8 KV RMS. I would try the 7.2 KV pole pig. No harm in trying.  If you find another 7.2 KV pig, you can put them in series.  :D I have seen that done.

One more thing to mention is that a higher voltage transformer is also better because of

E=0.5*C*(V**2)

where the capacitor energy, which also determines spark length, is proportional to the square of the voltage. The more charge you can put on that capacitor, within its safety limits, the better for discharge length.

I've never checked the no-load current on my pole transformer. There is usually a spec on this if you can find it or probably easier just to measure it yourself.

You may want to look at lots of pictures of how others have implemented their coils. It may give you some ideas. I looked at lots of pictures of coils before I built mine.


Thanks, working on something different today.

Offline davekni

  • High Voltage Technician
  • ***
  • Posts: 119
  • Karma: +4/-0
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: so far video
« Reply #6 on: October 14, 2019, 05:40:27 AM »
I'll second that 7.2kV RMS should be plenty.  My RSG coil uses two MOTs in series with resonant charging, so gets to about 9kV peak, which works well (with close gap spacing).

Did you say 27nF primary capacitance at 32kV?  I have no familiarity with pole-pig transformers.  Is there some resonant-charging effect that will get you much above 10kV?  If not, 27nF will be rather low energy per spark.  For my two-MOT coil, I used 680nF with a 3-turn primary coil to get reasonable energy per spark.
David Knierim

Offline thedoc298

  • High Voltage Experimenter
  • **
  • Posts: 65
  • Karma: +0/-0
    • View Profile
Re: so far video
« Reply #7 on: October 18, 2019, 04:42:52 AM »
I'll second that 7.2kV RMS should be plenty.  My RSG coil uses two MOTs in series with resonant charging, so gets to about 9kV peak, which works well (with close gap spacing).
Thanks, the 27nf is for the 60ma nst. The pig is 7200 rms and for a later build. Glad to know it will work.
Did you say 27nF primary capacitance at 32kV?  I have no familiarity with pole-pig transformers.  Is there some resonant-charging effect that will get you much above 10kV?  If not, 27nF will be rather low energy per spark.  For my two-MOT coil, I used 680nF with a 3-turn primary coil to get reasonable energy per spark.

High Voltage Forum

Re: so far video
« Reply #7 on: October 18, 2019, 04:42:52 AM »

 


* Recent Topics and Posts

post Re: Sense coil fabrication?
[Induction launchers, coil guns and rails guns]
klugesmith
Today at 09:54:31 PM
post Re: SGTC MK1 - An Accomplishment in Progress
[Spark gap Tesla coils]
jturnerkc
Today at 09:48:21 PM
post Re: Sense coil fabrication?
[Induction launchers, coil guns and rails guns]
klugesmith
Today at 08:59:57 PM
post Re: Cost reduction in consumer electrics
[Electronic circuits]
MRMILSTAR
December 06, 2019, 08:35:29 PM
post Re: Full bridge showing half the voltage
[Beginners]
plasma
December 06, 2019, 05:19:26 AM
post Re: Cost reduction in consumer electrics
[Electronic circuits]
davekni
December 06, 2019, 03:48:34 AM
post Re: Cost reduction in consumer electrics
[Electronic circuits]
the_anomaly
December 06, 2019, 03:35:39 AM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General chatting]
AstRii
December 06, 2019, 01:27:03 AM
post Re: Full bridge showing half the voltage
[Beginners]
plasma
December 05, 2019, 11:38:59 PM
post Re: Cost reduction in consumer electrics
[Electronic circuits]
Mads Barnkob
December 05, 2019, 07:33:01 PM
post Re: Cost reduction in consumer electrics
[Electronic circuits]
sjsimmo
December 05, 2019, 11:09:20 AM
post Cost reduction in consumer electrics
[Electronic circuits]
klugesmith
December 05, 2019, 07:25:20 AM
post Re: HV resistor in oil
[Voltage Multipliers]
MRMILSTAR
December 05, 2019, 05:52:11 AM
post Re: HV resistor in oil
[Voltage Multipliers]
davekni
December 05, 2019, 05:21:07 AM
post Re: HV resistor in oil
[Voltage Multipliers]
MRMILSTAR
December 04, 2019, 06:05:11 PM
post Re: Full bridge showing half the voltage
[Beginners]
shrad
December 04, 2019, 02:57:02 PM
post Re: Sense coil fabrication?
[Induction launchers, coil guns and rails guns]
Uspring
December 04, 2019, 12:40:51 PM
post Re: Full bridge showing half the voltage
[Beginners]
plasma
December 04, 2019, 11:20:25 AM
post Re: Sense coil fabrication?
[Induction launchers, coil guns and rails guns]
klugesmith
December 04, 2019, 08:28:15 AM
post Re: Full bridge showing half the voltage
[Beginners]
klugesmith
December 04, 2019, 07:41:21 AM
post Re: Sense coil fabrication?
[Induction launchers, coil guns and rails guns]
MRMILSTAR
December 04, 2019, 05:15:49 AM
post Re: HV resistor in oil
[Voltage Multipliers]
MRMILSTAR
December 04, 2019, 05:06:39 AM
post Re: HV resistor in oil
[Voltage Multipliers]
davekni
December 04, 2019, 04:31:16 AM
post Re: Full bridge showing half the voltage
[Beginners]
davekni
December 04, 2019, 04:26:38 AM
post Re: Sense coil fabrication?
[Induction launchers, coil guns and rails guns]
klugesmith
December 04, 2019, 04:10:16 AM
post Re: Sense coil fabrication?
[Induction launchers, coil guns and rails guns]
klugesmith
December 04, 2019, 12:28:15 AM
post Re: Full bridge showing half the voltage
[Beginners]
plasma
December 04, 2019, 12:11:32 AM
post Re: HV resistor in oil
[Voltage Multipliers]
johnf
December 03, 2019, 07:58:41 PM
post Re: Driving Nixie-tubes with arduino
[Electronic circuits]
johnf
December 03, 2019, 07:54:08 PM
post Re: Full bridge showing half the voltage
[Beginners]
klugesmith
December 03, 2019, 07:41:00 PM
post Re: Driving Nixie-tubes with arduino
[Electronic circuits]
kamelryttarn
December 03, 2019, 02:14:00 PM
post Re: Driving Nixie-tubes with arduino
[Electronic circuits]
Mads Barnkob
December 03, 2019, 01:24:00 PM
post Re: Driving Nixie-tubes with arduino
[Electronic circuits]
klugesmith
December 03, 2019, 10:45:58 AM
post Driving Nixie-tubes with arduino
[Electronic circuits]
kamelryttarn
December 03, 2019, 09:04:42 AM
post Re: Full bridge showing half the voltage
[Beginners]
plasma
December 03, 2019, 07:29:48 AM
post Re: HV resistor in oil
[Voltage Multipliers]
MRMILSTAR
December 03, 2019, 05:07:28 AM
post Re: HV resistor in oil
[Voltage Multipliers]
davekni
December 03, 2019, 04:34:46 AM
post Re: HV resistor in oil
[Voltage Multipliers]
MRMILSTAR
December 02, 2019, 09:06:07 PM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
T3sl4co1l
December 02, 2019, 10:51:33 AM
post Re: SGTC MK1 - An Accomplishment in Progress
[Spark gap Tesla coils]
jturnerkc
December 02, 2019, 05:49:05 AM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic circuits]
petespaco
December 02, 2019, 04:10:14 AM
post Re: SGTC MK1 - An Accomplishment in Progress
[Spark gap Tesla coils]
davekni
December 02, 2019, 04:09:37 AM
post Re: HV resistor in oil
[Voltage Multipliers]
davekni
December 02, 2019, 03:42:16 AM
post Re: HV resistor in oil
[Voltage Multipliers]
MRMILSTAR
December 01, 2019, 10:47:18 PM
post Re: HV resistor in oil
[Voltage Multipliers]
Mads Barnkob
December 01, 2019, 09:17:38 PM
post HV resistor in oil
[Voltage Multipliers]
MRMILSTAR
December 01, 2019, 08:51:31 PM
post Re: SGTC MK1 - An Accomplishment in Progress
[Spark gap Tesla coils]
jturnerkc
December 01, 2019, 07:32:44 PM
post Re: Corona on the.... GDT??
[Solid state Tesla coils]
Weston
December 01, 2019, 12:14:57 PM
post Re: SSTC low voltage at gate transformer and heating drivers
[Solid state Tesla coils]
davekni
December 01, 2019, 04:30:10 AM
post Re: SGTC MK1 - An Accomplishment in Progress
[Spark gap Tesla coils]
davekni
December 01, 2019, 02:56:39 AM

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