[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
RE: [TCML] Terry Filter
Hi Dex,
What is your reasoning in favor of NST's verses OBITS of equal
power/voltage. I will soon discover if this is true as I am building a obit
5000kv/23ma (1/2) the transformer. They are center tapped to ground and case
and current shunted I believe. They are potted in asphalt generally. It may
be interesting to un-pot one as the case in sealed when inverted.
Best,
Jim Mora
I'll post a picture when its done.
Happy Holidays everyone!
-----Original Message-----
From: tesla-bounces@xxxxxxxxxx [mailto:tesla-bounces@xxxxxxxxxx] On Behalf
Of Dex Dexter
Sent: Monday, December 21, 2009 12:13 PM
To: Tesla Coil Mailing List
Subject: Re: [TCML] Terry Filter
They don't ,but I wouldn't use OBIT in tesla coil
service.NSTs are better.
Dex
--- pbbrodie@xxxxxxxxxxxxx wrote:
From: "Paul Brodie" <pbbrodie@xxxxxxxxxxxxx>
To: "Tesla Coil Mailing List" <tesla@xxxxxxxxxx>
Subject: Re: [TCML] Terry Filter
Date: Mon, 21 Dec 2009 12:44:30 -0500
I recently purchased a 9kV 50mA OBIT or at least the seller says it is an
OBIT. This appears a little bit hefty for the purpose. Anyway, do these
transformers require the same sorts of protection that are used with neon
sign transformers?
Paul
Think Positive
----- Original Message -----
From: Dex Dexter
To: Tesla Coil Mailing List
Sent: Monday, December 21, 2009 05:23
Subject: RE: [TCML] Terry Filter
I run my static gap coil without any filter at all.
NST is 5kv/20ma ,and safety gap is set for
the breakdown voltage of aprox 10 kV peak.
I've never saw it arcing so the breakdown
voltage of my static gap is probably below 9 kV.
Position and way of connecting the gaps with respect to
NST is important.Both gaps should be paralleled with NST.
Dex
--- Gary.Lau@xxxxxx wrote:
From: "Lau, Gary" <Gary.Lau@xxxxxx>
To: Tesla Coil Mailing List <tesla@xxxxxxxxxx>
Subject: RE: [TCML] Terry Filter
Date: Mon, 21 Dec 2009 02:16:43 +0000
If you build a filter with MOV's targeting a 15kV NST, and you use a 9kV
NST, the MOV's will allow a peak voltage of something like 22-23kV before
they kick in. With a 9kV NST, the maximum voltage that *should* be allowed
is 9000 x 1.414 = 12726, call it 13-14kV. So it would be permitting
too-high voltages that should have been clamped. One needs to select the
correct number of MOV's for the NST voltage used, for the same reason that
one needs to set the safety gap for each situation.
Regards, Gary Lau
MA, USA
> -----Original Message-----
> From: tesla-bounces@xxxxxxxxxx [mailto:tesla-bounces@xxxxxxxxxx] On
> Behalf Of chipford@xxxxxxxxxxxxxx
> Sent: Sunday, December 20, 2009 8:31 PM
> To: tesla@xxxxxxxxxx
> Subject: [TCML] Terry Filter
>
> I have my terry filter about 50% done. While building it, I asked myself
a question.
> Why would a person build anything but a Terry Filter capable of
protecting a NST of
> 15,000 volts? I ordered 14 MOV's from dig-key. For 4 or 5 dollars more,
I could
> have had 16. Now if i want enough for a 15k trany, I gotta pay shipping
> again.Correct me if I am wrong. If I build a Terry filter capable of
protecting a 15K
> volt trany, I can use it to protect my 9000 volt NST without any
modifications. I bring
> this up because, as we all know, parts get swapped from coil to coil and
if I decide
> to built a larger coil with my 15k trany later on, I could've just moved
it over without
> worry. Am I wrong?
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla
_____________________________________________________________
Washington DC's Largest FREE Email service. ---> http://www.DCemail.com
---> A Washington Online Community Member --->
http://www.DCpages.com
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla
_____________________________________________________________
Washington DC's Largest FREE Email service. ---> http://www.DCemail.com --->
A Washington Online Community Member --->
http://www.DCpages.com
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla
No virus found in this incoming message.
Checked by AVG - www.avg.com
Version: 9.0.717 / Virus Database: 270.14.116/2580 - Release Date: 12/21/09
11:13:00
_______________________________________________
Tesla mailing list
Tesla@xxxxxxxxxx
http://www.pupman.com/mailman/listinfo/tesla