Murphy'sLaw I will say this about electricity off topic. Never underestimate Murphy'sLaw it will get you sometime when you least expect it. Receiving an electricalshock of any kind, can open ones eyes wide. Sure it can also kill you sorespect it but not fear it. If you are ever shocked bad & live you willdefinitely try to be more careful. So a shock may be a good thing it teachesyou to keep one hand in your pocket & not get a shocked as often ! & Green is Ground the worldround. In the real world electrical power can not always be turned off you needto work on live power sometimes & be extra careful. Heard in the old day'sthey hung jars under light fixtures to catch the juice.
On Friday, June 22, 2018 3:34 AM, Matthew Sweeney <msweeney23@xxxxxxxxx> wrote:
Great info, thanks for that!
So for my needs, I would like to isolate the circuit as much as possible
and even my NST case will be somewhat contained to prevent touching (yes it
will be cooled).
I will be running this coil outside with an extension cord, and thus any
line filter will not have direct connection to the mains box. So I should
be good to ground my secondary, Terry filter, and NST to RF ground?
Again this is a little weak coil with a single NST running a multi-gap
(quenched).
Thanks again!
Matt
On Tue, Jun 19, 2018, 9:02 PM Gary Lau <glau1024@xxxxxxxxx> wrote:
> Re. how to hook up an EMI line filter - I put up a web page detailing how
> to hook it up, how NOT to hook it up, and why. The full answer is more
> nuanced than just forwards or backwards - and again it involves grounding.
> See http://www.laushaus.com/tesla/emifilter.htm
>
> Now back to grounding. I previously wrote:
> > I can't think of any fault condition or inadvertent touch where having
> the NST case tied to mains ground offers any safety advantage.
>
> Actually I can.
> If one were to "assume" that touching the case of an energized NST was OK,
> and
> If the NST case were tied to an RF ground or counterpoise that did not have
> a low impedance path to mains-ground, and
> If some other body part of this person was in contact with a grounded
> object, and
> If the NST had developed an internal or wiring fault that provided a path
> from AC-HOT to the NST case,
> ... then there is a credible risk of shock. This scenario is far more
> plausible where the NST is powering a neon sign and the victim is not a
> high voltage enthusiast. Hopefully everyone reading this understands that
> touching ANYTHING on an operating Tesla coil is not a good idea.
> Unfortunately I cannot think of any way to both eliminate this hazard and
> to keep RF ground transients out of your mains.
>
> Gary Lau
> MA, USA
>
>
> <
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>
> On Tue, Jun 19, 2018 at 8:20 PM, Matthew Sweeney <msweeney23@xxxxxxxxx>
> wrote:
>
> > Thanks Dan, I did pickup some of those little line filters, but I have to
> > hook it up 'backwards' right?
> >
> > Matt
> >
> > On Tue, Jun 19, 2018, 4:06 PM Daniel Kunkel <dankunkel@xxxxxxxxx> wrote:
> >
> > > Matthew,
> > > You might consider using a commercial line filter to keep RF nasties
> out
> > of
> > > the supply line. You can get a 10-20amp until for around $10-20.
> > > ~Dan
> > > Kansas City area
> > >
> > > On Tue, Jun 19, 2018 at 10:57 AM, Matthew Sweeney <
> msweeney23@xxxxxxxxx>
> > > wrote:
> > >
> > > > Even for smaller coils (i.e. a single 15kv/30ma NST), should I
> consider
> > > > tying NST to a new/RF ground (8 ft ground rod) if I want to avoid any
> > > > transients into my neighbor circuits? I live in an old duplex house
> > with
> > > > horribly out of date wiring.
> > > >
> > > > I do have a Terry filter and line filter, but I need to be extra
> > > specially
> > > > careful. I assume that RF ground is also secondary ground correct
> (thus
> > > > RF).
> > > >
> > > > Any other steps I can take? Note that this is a traditional static
> gap
> > > > coil.
> > > >
> > > > Thanks!
> > > >
> > > > Matt
> > > >
> > > > On Tue, Jun 19, 2018, 9:52 AM Chris Boden <cboden@xxxxxxxxxxxxxxxx>
> > > wrote:
> > > >
> > > > > This depends on usage. If it's a little JL or you're just screwing
> > > around
> > > > > with an NST, mains ground is what you want. If it's part of a
> larger
> > TC
> > > > > system then RF ground is better.
> > > > >
> > > > > But regardless of application, Ground it.
> > > > >
> > > > > On Mon, Jun 18, 2018 at 9:40 PM, Gary Lau <glau1024@xxxxxxxxx>
> > wrote:
> > > > >
> > > > > > I disagree with the advice:
> > > > > > > 3. GROUND THE CASE OF THE NST
> > > > > >
> > > > > > The case of the NST is tied to RF ground and is full of high
> > voltage
> > > RF
> > > > > > transients that you do not want feeding into your mains.. Unless
> > the
> > > > > coil
> > > > > > is relatively low power and there is no alternate ground or
> > > > counterpoise
> > > > > > available, you should not be connecting RF ground to mains
> > ground. I
> > > > > can't
> > > > > > think of any fault condition or inadvertent touch where having
> the
> > > NST
> > > > > case
> > > > > > tied to mains ground offers any safety advantage.
> > > > > >
> > > > > > Regards, Gary Lau
> > > > > > MA, USA
> > > > > >
> > > > > > On Sun, Jun 17, 2018 at 6:44 PM, Chris Boden <
> > > cboden@xxxxxxxxxxxxxxxx>
> > > > > > wrote:
> > > > > >
> > > > > > > Greetings Mr.Janota :)
> > > > > > >
> > > > > > > NST's are current limited and operate typically at a maximum of
> > > 15kV
> > > > > > (with
> > > > > > > 12kV and lower being quite common as well).
> > > > > > > The typical max current output will be 60mA.
> > > > > > >
> > > > > > > What this means is it Most Likely, Probably.....Unusually....
> > wont'
> > > > kill
> > > > > > > you
> > > > > > > if you brush against the output, are a rigorously healthy
> adult,
> > > dry,
> > > > > and
> > > > > > > nontrivially lucky.
> > > > > > >
> > > > > > > This is as opposed to things like Pole Pigs at 10kVA or more
> (we
> > > have
> > > > > > > 100kVA pigs in the lab) with no current limiting which are
> > > reasonably
> > > > > > > considered to be fatal (it's not instant, and it hurts the
> whole
> > > > time).
> > > > > > > There are also pulse capacitors (typical in our lab is 20kV to
> > 50kV
> > > > > with
> > > > > > > 10kJ energies) those don't just kill you, they blow parts off.
> We
> > > > have
> > > > > > > 400lb caps here that are in the "clean you off the ceiling
> with a
> > > > > sponge"
> > > > > > > levels of deadly.
> > > > > > >
> > > > > > > That's a long way from your NST, but the idea across the
> spectrum
> > > is
> > > > > the
> > > > > > > same. These toys are not for the emotional, impulsive, or
> stupid.
> > > > They
> > > > > > will
> > > > > > > hurt you the moment you don't respect them, and kill you if
> > you're
> > > > > > > reckless.
> > > > > > >
> > > > > > > That's the point.
> > > > > > >
> > > > > > > There are millions of people who would like to own a powerful
> > Tesla
> > > > > Coil.
> > > > > > > But very, very few get that far. The fundamental price to own a
> > > coil
> > > > is
> > > > > > > simple, be smart enough to build one. It's not hard, but you
> have
> > > to
> > > > do
> > > > > > it
> > > > > > > yourself. Along that path you will have to learn hundreds of
> new
> > > > > things,
> > > > > > > foremost is safety and a healthy respect for HV. Consider how
> few
> > > > > people
> > > > > > > you know who have ever run a marathon. The rough number is
> often
> > > > quoted
> > > > > > as
> > > > > > > 1% of 1% of the people in America have ever run a marathon. The
> > > > number
> > > > > of
> > > > > > > people in the history of the world who have ever successfully
> > > built a
> > > > > > > working Tesla Coil wouldn't fill a single run of the Chicago
> > > > marathon.
> > > > > > This
> > > > > > > is a very small community.
> > > > > > >
> > > > > > > To the average person Electricity is composed mainly of magic.
> > It's
> > > > > > > dangerous and terrifying. In reality, it's just science. The
> > > > mechanisms
> > > > > > of
> > > > > > > electrical power have been pretty well worked out by people far
> > > > smarter
> > > > > > > than me. We can build chips at the nano-scale with billions of
> > > wires
> > > > > > only a
> > > > > > > few atoms wide carrying energies less than a mouse's fart, and
> we
> > > can
> > > > > > > wrangle million-volt power lines across the desert. But to the
> > > > average
> > > > > > > person they understand as little about how the power gets in
> > their
> > > > > > computer
> > > > > > > as they do about what actually happens when they flush the
> > toilet.
> > > > > > >
> > > > > > > You should have a respectful, healthy fear of HV, but not a
> > > crippling
> > > > > > one.
> > > > > > > It's not magic, and it won't jump across the room and bite you.
> > > Some
> > > > > > simple
> > > > > > > things to remember will help you a lot.
> > > > > > >
> > > > > > > 1. Keep the plug in your pocket when you're working on the NST.
> > If
> > > > the
> > > > > > plug
> > > > > > > isn't in your pocket, then don't touch it.
> > > > > > > 2. 15kV with a beginner wants a safe radius of 2 inches to
> > > anything,
> > > > > and
> > > > > > 3
> > > > > > > feet to anything that's alive. Keep the HV conductors 2 inches
> > from
> > > > the
> > > > > > > case and you're not going to have any problems.
> > > > > > > 3. GROUND THE CASE OF THE NST. The bottom-center hole on a US
> > > outlet
> > > > > (the
> > > > > > > mouth of the face) is Ground. This should connect to the
> > > uninsulated
> > > > > lug
> > > > > > on
> > > > > > > the side of the NST. The NST will have two big insulated lugs
> > (the
> > > HV
> > > > > > > terminals) two smaller insulated lugs right next to each other
> > (the
> > > > LV
> > > > > > > terminals), and one uninsulated lug that just looks like a bolt
> > > > > sticking
> > > > > > > out the side....that one is the ground.
> > > > > > >
> > > > > > > And lastly, while most of the people here would never admit it
> > (and
> > > > > > > certainly never publicly), the vast majority of us have been
> bit
> > at
> > > > > some
> > > > > > > point because we did something stupid and got a hard lesson in
> > > pain.
> > > > > I've
> > > > > > > been bit a few times and thankfully, by sheer dumb luck I
> > survived
> > > > > them,
> > > > > > >
> > > > > > > so far.
> > > > > > >
> > > > > > > Good luck :)
> > > > > > >
> > > > > > >
> > > > > > <http://www.avg.com/email-signature?utm_medium=email&;
> > > > > > utm_source=link&utm_campaign=sig-email&utm_content=webmail>
> > > > > > Virus-free.
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> > > > > > <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
> > > > > > _______________________________________________
> > > > > > Tesla mailing list
> > > > > > Tesla@xxxxxxxxxxxxxxxxxx
> > > > > > https://www.pupman.com/mailman/listinfo/tesla
> > > > > >
> > > > >
> > > > >
> > > > >
> > > > > --
> > > > >
> > > > > Chris Boden
> > > > > President
> > > > > The Geek Group National Science Institute
> > > > > www.thegeekgroup.org
> > > > >
> > > > > --
> > > > >
> > > > >
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> > is
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