Author Topic: My terry filter  (Read 125 times)

Offline thedoc298

  • High Voltage Experimenter
  • **
  • Posts: 66
  • Karma: +0/-0
    • View Profile
My terry filter
« on: October 11, 2019, 01:37:11 AM »
I have a couple of  30kv doorknob caps 500pf. With 15000 across them, that comes out to 3ma or 45watts that is prety hot. The fact that it is rated at 30kv does that mean it is good for the wattage. Never seen any with power rating on the ones on ebay.

Just did some testing and one good thing is its only 7500 across one cap to rf ground and after 5 min its just warm.

Also scored me a pig, only 7200 but it was free, so after get the current one going will switch over to pig power I just need Mrmlstar to roll me a big fat one, inductor.
« Last Edit: October 11, 2019, 02:11:13 AM by thedoc298 »

Offline MRMILSTAR

  • High Voltage Experimenter
  • **
  • Posts: 85
  • Karma: +3/-0
  • Cedar Rapids, Iowa
    • View Profile
Re: My terry filter
« Reply #1 on: October 11, 2019, 05:13:51 AM »
Ha ha. Start looking for those big E and I sections.

I use a low pass RC filter (so-called Terry filter) on my pole pig although it probably isn't necessary. I had the parts so why not, it can't hurt. I use two Murata 500 pF doorknob caps each rated for 30 KV, one for each leg of the HV output. These capacitors work with no problem with my 14.4 KV transformer output. My coil draws 6.5 KVA.

The capacitor spec you are looking for is continuous RMS current handling capability. Unfortunately, this spec is not always supplied. It is related to the capacitor's internal resistance. Doorknob capacitors generally have a very low internal resistance so they can handle a fair amount of continuous current. The biggest problem with them is that as they heat up, the capacitance can change. While important for a tuned circuit, it is non-critical for the single-pole low pass filter which is used for transformer protection.

Offline thedoc298

  • High Voltage Experimenter
  • **
  • Posts: 66
  • Karma: +0/-0
    • View Profile
Re: My terry filter
« Reply #2 on: October 11, 2019, 06:54:59 PM »
Ha ha. Start looking for those big E and I sections.

I use a low pass RC filter (so-called Terry filter) on my pole pig although it probably isn't necessary. I had the parts so why not, it can't hurt. I use two Murata 500 pF doorknob caps each rated for 30 KV, one for each leg of the HV output. These capacitors work with no problem with my 14.4 KV transformer output. My coil draws 6.5 KVA.

The capacitor spec you are looking for is continuous RMS current handling capability. Unfortunately, this spec is not always supplied. It is related to the capacitor's internal resistance. Doorknob capacitors generally have a very low internal resistance so they can handle a fair amount of continuous current. The biggest problem with them is that as they heat up, the capacitance can change. While important for a tuned circuit, it is non-critical for the single-pole low pass filter which is used for transformer protection.

I really appreciate all your help, just helps to have a second voice of someone that has done it before. I got that pig in my shop last night and could not believe how heavy they are. I use my welder for a ballast to test it out, still poped my 40 amp fuse after a bit.

High Voltage Forum

Re: My terry filter
« Reply #2 on: October 11, 2019, 06:54:59 PM »

 


* Recent Topics and Posts

post Re: my first DRSSTC is not working properly
[Dual Resonant Solid State Tesla coils]
Mads Barnkob
Today at 10:25:09 AM
post Re: SGTC MK1 - An Accomplishment in Progress
[Spark gap Tesla coils]
davekni
Today at 05:30:25 AM
post Re: IR wavelength in photoelectric smoke detectors?
[Light, lasers and optics]
klugesmith
November 19, 2019, 11:15:31 PM
post Re: coil Tesla in the space
[Dual Resonant Solid State Tesla coils]
Mads Barnkob
November 19, 2019, 11:28:10 AM
post Re: RF Amplifier for Cubesat plasma thruster
[Electronic circuits]
Weston
November 19, 2019, 08:56:49 AM
post Re: SGTC MK1 - An Accomplishment in Progress
[Spark gap Tesla coils]
jturnerkc
November 19, 2019, 06:25:49 AM
post Re: my first DRSSTC is not working properly
[Dual Resonant Solid State Tesla coils]
davekni
November 19, 2019, 06:17:03 AM
post Re: SSTC low voltage at gate transformer and heating drivers
[Solid state Tesla coils]
davekni
November 19, 2019, 06:03:37 AM
post Disc launcher attachment
[Induction launchers, coil guns and rails guns]
MRMILSTAR
November 19, 2019, 05:51:39 AM
post Re: SGTC MK1 - An Accomplishment in Progress
[Spark gap Tesla coils]
davekni
November 19, 2019, 05:47:34 AM
post Re: SGTC MK1 - An Accomplishment in Progress
[Spark gap Tesla coils]
jturnerkc
November 19, 2019, 12:49:52 AM
post Re: SSTC low voltage at gate transformer and heating drivers
[Solid state Tesla coils]
babass
November 18, 2019, 09:19:26 PM
post my first DRSSTC is not working properly
[Dual Resonant Solid State Tesla coils]
zanikk
November 18, 2019, 06:56:18 PM
post Re: IR wavelength in photoelectric smoke detectors?
[Light, lasers and optics]
Uspring
November 18, 2019, 02:38:14 PM
post Re: coil Tesla in the space
[Dual Resonant Solid State Tesla coils]
Uspring
November 18, 2019, 01:46:06 PM
post Re: SGTC MK1 - An Accomplishment in Progress
[Spark gap Tesla coils]
Mads Barnkob
November 18, 2019, 12:21:53 PM
post Re: IR wavelength in photoelectric smoke detectors?
[Light, lasers and optics]
shrad
November 18, 2019, 09:01:41 AM
post Re: RF Amplifier for Cubesat plasma thruster
[Electronic circuits]
shrad
November 18, 2019, 08:57:05 AM
post Re: IR wavelength in photoelectric smoke detectors?
[Light, lasers and optics]
klugesmith
November 18, 2019, 04:48:39 AM
post Re: SGTC MK1 - An Accomplishment in Progress
[Spark gap Tesla coils]
jturnerkc
November 18, 2019, 03:30:02 AM
post Re: SSTC low voltage at gate transformer and heating drivers
[Solid state Tesla coils]
davekni
November 18, 2019, 02:53:29 AM
post Re: SGTC MK1 - An Accomplishment in Progress
[Spark gap Tesla coils]
davekni
November 18, 2019, 01:59:24 AM
post Re: SGTC MK1 - An Accomplishment in Progress
[Spark gap Tesla coils]
jturnerkc
November 18, 2019, 12:07:38 AM
post Re: IR wavelength in photoelectric smoke detectors?
[Light, lasers and optics]
klugesmith
November 17, 2019, 07:15:01 PM
post Re: SSTC low voltage at gate transformer and heating drivers
[Solid state Tesla coils]
babass
November 17, 2019, 04:06:01 PM
post Re: SSTC low voltage at gate transformer and heating drivers
[Solid state Tesla coils]
davekni
November 17, 2019, 06:26:58 AM
post Re: Measuring permanent magnets
[Electronic circuits]
klugesmith
November 17, 2019, 03:02:45 AM
post Re: SSTC low voltage at gate transformer and heating drivers
[Solid state Tesla coils]
babass
November 16, 2019, 09:20:41 PM
post Re: SSTC low voltage at gate transformer and heating drivers
[Solid state Tesla coils]
Mads Barnkob
November 16, 2019, 08:03:58 PM
post Re: SSTC low voltage at gate transformer and heating drivers
[Solid state Tesla coils]
babass
November 16, 2019, 07:27:30 PM
post Re: SSTC low voltage at gate transformer and heating drivers
[Solid state Tesla coils]
davekni
November 16, 2019, 06:55:16 PM
post Re: SSTC low voltage at gate transformer and heating drivers
[Solid state Tesla coils]
thedoc298
November 16, 2019, 05:19:05 PM
post Re: SSTC low voltage at gate transformer and heating drivers
[Solid state Tesla coils]
babass
November 16, 2019, 01:33:17 PM
post Re: SSTC low voltage at gate transformer and heating drivers
[Solid state Tesla coils]
davekni
November 16, 2019, 04:56:44 AM
post Re: SGTC MK1 - An Accomplishment in Progress
[Spark gap Tesla coils]
davekni
November 16, 2019, 04:13:35 AM
post Re: SSTC low voltage at gate transformer and heating drivers
[Solid state Tesla coils]
babass
November 16, 2019, 01:21:10 AM
post Re: coil Tesla in the space
[Dual Resonant Solid State Tesla coils]
Alexis
November 15, 2019, 08:14:00 PM
post Re: coil Tesla in the space
[Dual Resonant Solid State Tesla coils]
Mads Barnkob
November 15, 2019, 05:40:33 PM
post Re: SGTC MK1 - An Accomplishment in Progress
[Spark gap Tesla coils]
jturnerkc
November 15, 2019, 03:59:48 PM
post coil Tesla in the space
[Dual Resonant Solid State Tesla coils]
Alexis
November 15, 2019, 03:35:38 PM
post Re: SSTC low voltage at gate transformer and heating drivers
[Solid state Tesla coils]
davekni
November 15, 2019, 05:18:19 AM
post SSTC low voltage at gate transformer and heating drivers
[Solid state Tesla coils]
babass
November 14, 2019, 05:40:58 PM
post Re: Welcome new members, come say hello and tell a little about yourself :)
[General chatting]
babass
November 14, 2019, 05:13:01 PM
post Re: Royer oscillator (ZVS) driven Jacob's ladder, E80 core transformer
[Transformer (ferrite core)]
T3sl4co1l
November 14, 2019, 01:50:30 PM
post Re: Royer oscillator (ZVS) driven Jacob's ladder, E80 core transformer
[Transformer (ferrite core)]
Uspring
November 14, 2019, 11:45:15 AM
post Re: Problems with my first DRSSTC
[Dual Resonant Solid State Tesla coils]
davekni
November 14, 2019, 05:35:19 AM
post Re: SGTC MK1 - An Accomplishment in Progress
[Spark gap Tesla coils]
davekni
November 14, 2019, 05:25:57 AM
post Re: How to measure voltage output of AC flyback transformer
[Transformer (ferrite core)]
davekni
November 14, 2019, 04:49:57 AM
post Re: Royer oscillator (ZVS) driven Jacob's ladder, E80 core transformer
[Transformer (ferrite core)]
davekni
November 14, 2019, 04:32:50 AM
post Re: How to measure voltage output of AC flyback transformer
[Transformer (ferrite core)]
profdc9
November 13, 2019, 06:00:58 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