[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [TCML] Looking for Pole Pig Capacitors
Travis,
Yea, the DC Res charging allows the versatility of a widely variable bps rate. I think you would also need a de-Q-ing diode between the storage cap and the primary cap as well. I have personally never built a DC Res charging
power supply so you may do better seeking the advice of someone who has actual experience with this type of coil system. I know Roger Smith's big coil is a DC Res system. Maybe he could chip in on this?
David Rieben
On Nov 28, 2011, at 10:52 AM, Travis Tabbal <travis@xxxxxxxxxx> wrote:
> Thanks for the great info. I wondered if I would be able to charge a .3uF
> with my 10kVA 14.4KV pig. LTR is an option, but I don't have a sync
> motor... DC resonant looked interesting to me though. Other than needing a
> big cap rated for the transformer voltage, and diodes along with the
> inductor, anything to look out for? I think one of my pigs can do 7.2Kv, so
> the DC resonant mode would kick it up to 14.4 if I'm reading properly. Does
> the DC filter cap see the inductive kick? I know the primary cap does.
> Designing for 28kV sounds.... interesting... not sure I want to go there...
>
>
> On Sat, Nov 26, 2011 at 2:33 PM, drieben <drieben@xxxxxxx> wrote:
>
>> Hi Travis,
>>
>> No, I suppose there really isn't a reason, other
>> than that it would take a power supply of con-
>> siderable magnitude to be able to fully charge
>> a .3 uFd cap, at 14.4 kV (maybe more than the
>> typical residential, single phase electrical service could
>> reliably provide), especially with an ARSG churning
>> out several hundred breaks per second. This is
>> the typical way in which a classic SG driven, 14.4 kV
>> pole pig powered coil system is operated. If one was
>> so inclined to operate their pig powered system
>> LTR, with an SRSG at 120 BPS, or a DC resonant
>> charging power supply with a pole pig (ala - Roger Smith),
>> OR, if you are operating with a lower voltage output pole
>> pig, then a single unit of this persuation may be your ticket
>> to success ;^) Amir Mojarradi was looking for a suitable
>> capacitor in the 0.1 to 0.2 uFd range (and rightfully so
>> for the size and specs of his coil system, as his coil was
>> running great w/ 0.14 uFd), so that was the reason for
>> my suggestion as to the feasability of two of these units
>> in a series configuration.
>>
>> Also, I would consider a 50 kV(DC) rating on a commercial
>> pulse cap to be on the very low end of the acceptable spec limit
>> for a suitable primary cap in a coil system driven by a 14,400
>> volt pole pig (especially with the high charge/discharge BPS
>> duty cycle of an ARSG). As Amir can now handily attest, a
>> 35 kVDC rating is certainly NOT sufficient for a 14.4 kVAC
>> pole pig power supply! I have also personally experienced
>> a failure of a 0.1 uFd, 50 kV rated Hipotronics pulse cap
>> in my Green Monster Tesla coil system and I probably
>> only got 2-3 hours of total run time out of it before failure.
>> My GM coil also utilizes a 10 kVA, 240V/14.4 kV pig.
>> An autopsy revealed that the failure mode of the Hipotronics
>> cap was strickly dielectric breakdown, due to overvoltage -
>> NOT over current. The cap unit had no external signs of
>> internal failure - no case rupture or external bulging/swelling,
>> and the Hipotronics unit didn't get warm during operation.
>> I am currently using a 31885 Maxwell 0.1 uFd, 75 kVDC
>> rated Maxwell pulse cap and have had no more problems.
>> The 100 kV rating of two 50 kV rated units, in series, should
>> prove nearly bullet-proof for a 14.4 kV driven system. ;^)
>>
>> Happy Sparkin',
>> David
>>
>>
>> ----- Original Message ----- From: "Travis Tabbal" <travis@xxxxxxxxxx>
>> To: "Tesla Coil Mailing List" <tesla@xxxxxxxxxx>
>> Sent: Friday, November 25, 2011 9:45 PM
>> Subject: Re: [TCML] Looking for Pole Pig Capacitors
>>
>>
>> I've been considering one of those for a coil with similar power input.
>>> Any
>>> reason .3uf wouldn't work with a properly tuned primary and top load?
>>> On Nov 25, 2011 8:31 PM, "Roger Smith" <rwsmith@xxxxxxxxxxxxxx> wrote:
>>>
>>> On 11/25/2011 5:53 PM, Amir Mojarradi wrote:
>>>>
>>>>
>>>>> Hello everyone!
>>>>>
>>>>> I recently destroyed a 0.03 uFd 35kv Maxwell capacitor (#37667) of
>>>>> which
>>>>> I was using (4) in parallel to achieve 0.15 uFd at 35kv. I am running a
>>>>> 10kva 14.7kv pole pig powered coil with a 12in diameter, 57" winding
>>>>> length
>>>>> secondary, and a 60in major/ 12in minor diameter toroid. The single
>>>>> capacitor cracked in half and splashed oil for a good 8 feet.
>>>>> Evidently, my
>>>>> configuration was poorly designed to handle the ~ 15 kv input.
>>>>> Apparently,
>>>>> people have had this issue before and I was previously warned by David
>>>>> Rieben.
>>>>>
>>>>> David suggested 2 of these Aerovox 0.305 uFd 50KV Capacitors in series,
>>>>> but that would be a bit pricey given the shipping for about152 lbs!
>>>>> Yet, I
>>>>> am considering them.
>>>>> http://www.ebay.com/itm/****Aerovox-Tesla-50KV-High-**<http://www.ebay.com/itm/**Aerovox-Tesla-50KV-High-**>
>>>>> Voltage-Aerostor-Pulse-****Capacitor-/200679608603?pt=LH_****
>>>>> DefaultDomain_0&hash=****item2eb96fd11b<http://www.**
>>>>> ebay.com/itm/Aerovox-Tesla-**50KV-High-Voltage-Aerostor-**
>>>>> Pulse-Capacitor-/200679608603?**pt=LH_DefaultDomain_0&hash=**
>>>>> item2eb96fd11b<http://www.ebay.com/itm/Aerovox-Tesla-50KV-High-Voltage-Aerostor-Pulse-Capacitor-/200679608603?pt=LH_DefaultDomain_0&hash=item2eb96fd11b>
>>>>>>
>>>>>
>>>>>
>>>>> Is anyone willing to sell pole pig suitable capacitors, either single
>>>>> unit or several, for approximately a 0.15uFd 50KV + rated capacitor
>>>>> bank?
>>>>> I'm a student and my budget is around $100-200 and I will of course pay
>>>>> for
>>>>> shipping and handling; I live near Pasadena, California. Please let me
>>>>> know
>>>>> if you have any comments or suggestions regarding possible capacitor
>>>>> choices; they will be greatly appreciated.
>>>>>
>>>>> Thank you for your kindness,
>>>>>
>>>>> Amir Mojarradi
>>>>>
>>>>>
>>>>>
>>>>> ______________________________****_________________
>>>>> Tesla mailing list
>>>>> Tesla@xxxxxxxxxx
>>>>> http://www.pupman.com/mailman/****listinfo/tesla<http://www.pupman.com/mailman/**listinfo/tesla>
>>>>> <http://www.**pupman.com/mailman/listinfo/**tesla<http://www.pupman.com/mailman/listinfo/tesla>
>>>>>>
>>>>>
>>>>>
>>>>> Those Aerovox capacitors sound like a good deal to me. Im tempted to
>>>>>
>>>> get a couple myself but if I made my coil any more powerful I would have
>>>> to
>>>> take it outside to run it. Your set up sounds pretty awesome. Do you
>>>> have any pictures?
>>>>
>>>> Roger
>>>> ______________________________****_________________
>>>> Tesla mailing list
>>>> Tesla@xxxxxxxxxx
>>>> http://www.pupman.com/mailman/****listinfo/tesla<http://www.pupman.com/mailman/**listinfo/tesla>
>>>> <http://www.**pupman.com/mailman/listinfo/**tesla<http://www.pupman.com/mailman/listinfo/tesla>
>>>>>
>>>>
>>>> ______________________________**_________________
>>> Tesla mailing list
>>> Tesla@xxxxxxxxxx
>>> http://www.pupman.com/mailman/**listinfo/tesla<http://www.pupman.com/mailman/listinfo/tesla>
>>>
>>
>> ______________________________**_________________
>> Tesla mailing list
>> Tesla@xxxxxxxxxx
>> http://www.pupman.com/mailman/**listinfo/tesla<http://www.pupman.com/mailman/listinfo/tesla>
>>
> _______________________________________________
> Tesla mailing list
> Tesla@xxxxxxxxxx
> http://www.pupman.com/mailman/listinfo/tesla
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla