OT: Lightning surges

Discussion in 'rec.audio.pro' started by Jay Levitt, Aug 5, 2003.

  1. A subpanel is not necessary to ground separately, but a new SERVICE needs to
    be grounded separately. A subpanel runs off a circuit from the panel using
    whatever breaker/wire combination necessary to handle the amperage. But in
    Jay's case, if BOTH are 200 Amp circuits, well, there's no breaker big
    enough to do that job except in a new service panel, so probably Jay DOES
    need the second panel to be grounded to it's own ground point. It cannot be
    grounded to the original service's grounding point or tied back into that
    braid.

    --


    Roger W. Norman
    SirMusic Studio
    Roger@SirMusicStudio.com
    301-585-4681




    "Scott Dorsey" <kludge@panix.com> wrote in message
    news:bgtugp$21l$1@panix2.panix.com...
    > Jay Levitt <jay+news@jay.fm> wrote:
    > >
    > >The ground itself is a thick braided cable, 3/0 gauge if I'm reading the
    > >smudged printing correctly. Oddly, I only see this cable going to one
    > >of the two panels, and one is NOT a sub-panel of the other; perhaps the
    > >ground is tied between them with regular Romex? These are 200-amp
    > >panels, FWIW.

    >
    > The code says that each individual service needs to be grounded, so that
    > second panel should have a connection to a ground. Pull the cover off
    > and look inside and see if it doesn't.
    >
    > It might be done with insulated wire, if the installing electrician had
    > some lying around, but that is not necessary or useful and costs more.
    >
    > >The other bad part is that the ground cable runs at LEAST 30 feet before
    > >disappearing into a crawlspace. That doesn't seem like a good thing. I
    > >suspect that this ground wire was not redone when the house was rewired,
    > >so it could be as old as 1970, when the house was first wired (it used
    > >to be a carriage house). Heck, it could be going nowhere at all
    > >anymore.

    >
    > The code says this is okay, as long as "the ground electrode is as near
    > as practicable to and preferably in the same area as the grounding

    conductor
    > connection to the system" (250-26C).
    >
    > >Interestingly, nothing in my studio seems to have been damaged. I
    > >assumed that was because of the Equitech isolation panel, but perhaps
    > >it's actually because the studio has its own ground rod, which is much
    > >more likely to be done correctly. That's all behind drywall, so I can't
    > >see where it goes.

    >
    > The isolation systems provide some isolation from trash on the power
    > lines, but they don't do anything about polluted grounds.
    >
    > Does the studio have a seperate service? If so, it should have an

    individual
    > ground.
    >
    > >My electrician's had a family emergency, but when he gets back to work,
    > >maybe he can shed some (battery-powered) light on the grounding system
    > >here.

    >
    > Go to the bookstore and get a copy of the NEC. It's lots of fun to try
    > and figure out.
    > --scott
    >
    > --
    > "C'est un Nagra. C'est suisse, et tres, tres precis."
  2. You don't ground a subpanel unless you are effectively making it another
    service. Technically, what I did (run a 60 amp circuit to the woodshop
    subpanel with a grounding rod) causes that to be another service, but code
    wise there should be another run of electrical from the street to that panel
    to create a new service. So not having the grounding braid from both panels
    is incorrect in your situation.

    Most likely your grounding braid simply ties to a grounding rod in the crawl
    space. Of course, you can always pull on the damned thing and see if it's
    hooked up to anything. But you seriously need to have your electrician look
    at the grounding and get it fixed, if what you report is correct.

    --


    Roger W. Norman
    SirMusic Studio
    Roger@SirMusicStudio.com
    301-585-4681




    "Jay Levitt" <jay+news@jay.fm> wrote in message
    news:MPG.199b43f7987efb409899ed@news-east.giganews.com...
    > In article <bgq0c0$lt0$1@panix2.panix.com>, kludge@panix.com says...
    > > Ground impedance at very high frequencies is a big issue, which is why
    > > the ground wire has to go from the panel straight to the rod without
    > > any loops or kinks along the way. Lightning is a very fast risetime
    > > pulse, so you need to think about stuff in the MHz region and not just
    > > DC.

    >
    > Interesting and educational.. thanks. I realized that code is only a
    > minimum standard, but hadn't thought about the vast difference in
    > requirements between a safety ground and a lightning discharge.
    >
    > The ground from my panel is not via the water pipe, although (as
    > mentioned elsewhere in the thread it's bonded to that, and in fact any
    > gaps in that (e.g. water filter, softener) have large jumpers.
    >
    > The ground itself is a thick braided cable, 3/0 gauge if I'm reading the
    > smudged printing correctly. Oddly, I only see this cable going to one
    > of the two panels, and one is NOT a sub-panel of the other; perhaps the
    > ground is tied between them with regular Romex? These are 200-amp
    > panels, FWIW.
    >
    > The other bad part is that the ground cable runs at LEAST 30 feet before
    > disappearing into a crawlspace. That doesn't seem like a good thing. I
    > suspect that this ground wire was not redone when the house was rewired,
    > so it could be as old as 1970, when the house was first wired (it used
    > to be a carriage house). Heck, it could be going nowhere at all
    > anymore.
    >
    > Interestingly, nothing in my studio seems to have been damaged. I
    > assumed that was because of the Equitech isolation panel, but perhaps
    > it's actually because the studio has its own ground rod, which is much
    > more likely to be done correctly. That's all behind drywall, so I can't
    > see where it goes.
    >
    > My electrician's had a family emergency, but when he gets back to work,
    > maybe he can shed some (battery-powered) light on the grounding system
    > here.
    >
    > --
    > Jay Levitt |
    > Wellesley, MA | Hi!
    > Faster: jay at jay dot eff-em | Where are we going?
    > http://www.jay.fm | Why am I in this handbasket?
  3. Don't be a wimp. Two screws and you'd really have to fuck up to "brush" any
    wires. Electricians install my previously run circuits all the time without
    bringing the house down. However, if you like resetting all your clocks
    again...! <g> And besides, one can never be too safe around electricity,
    especially service panels. I regularly open mine because I'm always running
    new circuits, but regularly may mean once a year.

    --


    Roger W. Norman
    SirMusic Studio
    Roger@SirMusicStudio.com
    301-585-4681




    "Jay Levitt" <jay+news@jay.fm> wrote in message
    news:MPG.199c7ff27108c41c9899f1@news-east.giganews.com...
    > In article <bgtugp$21l$1@panix2.panix.com>, kludge@panix.com says...
    > > Jay Levitt <jay+news@jay.fm> wrote:
    > > >
    > > >The ground itself is a thick braided cable, 3/0 gauge if I'm reading

    the
    > > >smudged printing correctly. Oddly, I only see this cable going to one
    > > >of the two panels, and one is NOT a sub-panel of the other; perhaps the
    > > >ground is tied between them with regular Romex? These are 200-amp
    > > >panels, FWIW.

    > >
    > > The code says that each individual service needs to be grounded, so that
    > > second panel should have a connection to a ground. Pull the cover off
    > > and look inside and see if it doesn't.

    >
    > I actually need to pull the cover off to take photos for Cutler-Hammer
    > anyway. I presume that this is the sort of operation I'd want to shut
    > the main power off to do...? I worry about the (metal) panel brushing
    > against live wires, etc. as I remove it.
    >
    > > >The other bad part is that the ground cable runs at LEAST 30 feet

    before
    > > >disappearing into a crawlspace. That doesn't seem like a good thing.

    I
    > > >suspect that this ground wire was not redone when the house was

    rewired,
    > > >so it could be as old as 1970, when the house was first wired (it used
    > > >to be a carriage house). Heck, it could be going nowhere at all
    > > >anymore.

    > >
    > > The code says this is okay, as long as "the ground electrode is as near
    > > as practicable to and preferably in the same area as the grounding

    conductor
    > > connection to the system" (250-26C).

    >
    > I figured it was OK for code, but presumably bad for lightning
    > discharge, yes?
    >
    > > >Interestingly, nothing in my studio seems to have been damaged. I
    > > >assumed that was because of the Equitech isolation panel, but perhaps
    > > >it's actually because the studio has its own ground rod, which is much
    > > >more likely to be done correctly. That's all behind drywall, so I

    can't
    > > >see where it goes.

    > >
    > > The isolation systems provide some isolation from trash on the power
    > > lines, but they don't do anything about polluted grounds.

    >
    > Is that true even for the balanced power systems?
    >
    > > Does the studio have a seperate service? If so, it should have an

    individual
    > > ground.

    >
    > Nope, it doesn't - the Equitech panel is run off a 70A breaker on a
    > nearby sub-panel. However, the design for the studio specified a
    > separate, way-the-hell-oversized ground for audio reasons.
    >
    >
    > > Go to the bookstore and get a copy of the NEC. It's lots of fun to try
    > > and figure out.

    >
    > I'd rather get a hundred thousand paper cuts on my face...
    >
    > --
    > Jay Levitt |
    > Wellesley, MA | Hi!
    > Faster: jay at jay dot eff-em | Where are we going?
    > http://www.jay.fm | Why am I in this handbasket?
  4. A subpanel SHOULD NOT be running to a separate ground. The ground runs back
    from the subpanel to the service or it's a real, separate service. A new
    service needs grounding. A subpanel should not be grounded. 70 Amps
    requires 6/2 cable for anything less than 150 feet, so your Equitech panel
    is indeed a new service and needs to have it's own ground. If it doesn't
    have 6/2 cable or larger, then it's the wrong wire, and it's wired wrong.

    Damn, you have a mishmash of electrical in your house.

    --


    Roger W. Norman
    SirMusic Studio
    Roger@SirMusicStudio.com
    301-585-4681




    "Jay Levitt" <jay+news@jay.fm> wrote in message
    news:MPG.199c7ff27108c41c9899f1@news-east.giganews.com...
    > In article <bgtugp$21l$1@panix2.panix.com>, kludge@panix.com says...
    > > Jay Levitt <jay+news@jay.fm> wrote:
    > > >
    > > >The ground itself is a thick braided cable, 3/0 gauge if I'm reading

    the
    > > >smudged printing correctly. Oddly, I only see this cable going to one
    > > >of the two panels, and one is NOT a sub-panel of the other; perhaps the
    > > >ground is tied between them with regular Romex? These are 200-amp
    > > >panels, FWIW.

    > >
    > > The code says that each individual service needs to be grounded, so that
    > > second panel should have a connection to a ground. Pull the cover off
    > > and look inside and see if it doesn't.

    >
    > I actually need to pull the cover off to take photos for Cutler-Hammer
    > anyway. I presume that this is the sort of operation I'd want to shut
    > the main power off to do...? I worry about the (metal) panel brushing
    > against live wires, etc. as I remove it.
    >
    > > >The other bad part is that the ground cable runs at LEAST 30 feet

    before
    > > >disappearing into a crawlspace. That doesn't seem like a good thing.

    I
    > > >suspect that this ground wire was not redone when the house was

    rewired,
    > > >so it could be as old as 1970, when the house was first wired (it used
    > > >to be a carriage house). Heck, it could be going nowhere at all
    > > >anymore.

    > >
    > > The code says this is okay, as long as "the ground electrode is as near
    > > as practicable to and preferably in the same area as the grounding

    conductor
    > > connection to the system" (250-26C).

    >
    > I figured it was OK for code, but presumably bad for lightning
    > discharge, yes?
    >
    > > >Interestingly, nothing in my studio seems to have been damaged. I
    > > >assumed that was because of the Equitech isolation panel, but perhaps
    > > >it's actually because the studio has its own ground rod, which is much
    > > >more likely to be done correctly. That's all behind drywall, so I

    can't
    > > >see where it goes.

    > >
    > > The isolation systems provide some isolation from trash on the power
    > > lines, but they don't do anything about polluted grounds.

    >
    > Is that true even for the balanced power systems?
    >
    > > Does the studio have a seperate service? If so, it should have an

    individual
    > > ground.

    >
    > Nope, it doesn't - the Equitech panel is run off a 70A breaker on a
    > nearby sub-panel. However, the design for the studio specified a
    > separate, way-the-hell-oversized ground for audio reasons.
    >
    >
    > > Go to the bookstore and get a copy of the NEC. It's lots of fun to try
    > > and figure out.

    >
    > I'd rather get a hundred thousand paper cuts on my face...
    >
    > --
    > Jay Levitt |
    > Wellesley, MA | Hi!
    > Faster: jay at jay dot eff-em | Where are we going?
    > http://www.jay.fm | Why am I in this handbasket?
  5. Then run two rods, tying those together with some #3 braid, and ground to
    one. Gives the effective grounding of an 8' rod in a 4 foot depth. The
    bigger the rod, the better! <g>

    --


    Roger W. Norman
    SirMusic Studio
    Roger@SirMusicStudio.com
    301-585-4681




    "ScotFraser" <scotfraser@aol.com> wrote in message
    news:20030806164743.00947.00000078@mb-m11.aol.com...
    > << You can get air powered
    > palm nailers that will take a #6 8' copper rod and put it 7' 11" into the
    > ground in about 15 seconds. I think that's the thing that scares most
    > people from doing their own grounding work. Trying to drive the rod in.
    > Short work with the right tools. >>
    >
    > Not where I live. There's solid rock about 4 feet down. Both studio ground

    rods
    > I've installed over the years just stopped right there & the biggest

    sledges in
    > the hands of the strongest guys on site just couldn't get it any further,

    while
    > completely mushrooming the top. So that's where we cut it off.
    >
    >
    > Scott Fraser
  6. No common ground points for boxes, please. The new service (the Equitech)
    should have it's own ground point, so he did the right thing.

    --


    Roger W. Norman
    SirMusic Studio
    Roger@SirMusicStudio.com
    301-585-4681




    "Jay Levitt" <jay+news@jay.fm> wrote in message
    news:MPG.199cf01c783c0d1c9899f2@news-east.giganews.com...
    > >
    > > >> Does the studio have a seperate service? If so, it should have an

    individual
    > > >> ground.
    > > >
    > > >Nope, it doesn't - the Equitech panel is run off a 70A breaker on a
    > > >nearby sub-panel. However, the design for the studio specified a
    > > >separate, way-the-hell-oversized ground for audio reasons.

    > >
    > > Wait, so the subpanel is grounded seperately? With additional lightning
    > > arrestors at the subpanel?

    >
    > According to the plans, there should be a separate 4-gauge ground cable
    > running from the Equitech to the main ground rod. I seem to recall the
    > electrician telling me he just sunk a separate ground rod to keep the
    > run short. There are no separate lightning arrestors on the Equitech,
    > but it is downstream of the main panel which has them...
    >
    > ----------------- ---------------- ----------------
    > | 200A Panel A |-----|100A sub-panel|---|Equitech panel|
    > -|w/suppressor|-- ---------------- ----------------
    > | |
    > | really long ground braid | ground #2
    > V V
    >
    > -----------------
    > | 200A Panel B |
    > -|w/suppressor|--
    > |
    > |
    > V
    >
    > --
    > Jay Levitt |
    > Wellesley, MA | Hi!
    > Faster: jay at jay dot eff-em | Where are we going?
    > http://www.jay.fm | Why am I in this handbasket?
  7. Dave Martin

    Dave Martin Guest

    "Roger W. Norman" <rnorman@starpower.net> wrote to Scott Dorsey>

    Know anything about doing brick mason
    > work or even how to mix mortar to the right consistency? <g>
    >

    Somehow, I'm afraid that he does...

    --
    Dave Martin
    Java Jive Studio
    Nashville, TN
    www.javajivestudio.com
  8. Jay Levitt

    Jay Levitt Guest

    In article <bh08f7$kv2$1@bob.news.rcn.net>, rnorman@starpower.net
    says...
    > A subpanel SHOULD NOT be running to a separate ground. The ground runs back
    > from the subpanel to the service or it's a real, separate service. A new
    > service needs grounding. A subpanel should not be grounded. 70 Amps
    > requires 6/2 cable for anything less than 150 feet, so your Equitech panel
    > is indeed a new service and needs to have it's own ground.


    I'm confused. I thought a "new service" means that it's actually a
    parallel feed from the street - e.g. right now I have two 200-amp
    services going to two main panels (with two big shutoffs outside). But
    the Equitech is hanging off a 70A breaker in a subpanel, as depicted in
    my stunningly aesthetic diagram elsewhere in this thread.. am I
    misunderstanding what a service is, or is the whole thing just wired
    wrong?

    I am starting to wonder if maybe I shouldn't wait for this electrician
    to get back to work, but should instead call someone else, and get a
    second pair of eyes on it...

    --
    Jay Levitt |
    Wellesley, MA | Hi!
    Faster: jay at jay dot eff-em | Where are we going?
    http://www.jay.fm | Why am I in this handbasket?
  9. Scott Dorsey

    Scott Dorsey Guest

    Jay Levitt <jay+news@jay.fm> wrote:
    >In article <bh08f7$kv2$1@bob.news.rcn.net>, rnorman@starpower.net
    >says...
    >> A subpanel SHOULD NOT be running to a separate ground. The ground runs back
    >> from the subpanel to the service or it's a real, separate service. A new
    >> service needs grounding. A subpanel should not be grounded. 70 Amps
    >> requires 6/2 cable for anything less than 150 feet, so your Equitech panel
    >> is indeed a new service and needs to have it's own ground.

    >
    >I'm confused. I thought a "new service" means that it's actually a
    >parallel feed from the street - e.g. right now I have two 200-amp
    >services going to two main panels (with two big shutoffs outside).


    Right.

    >But
    >the Equitech is hanging off a 70A breaker in a subpanel, as depicted in
    >my stunningly aesthetic diagram elsewhere in this thread.. am I
    >misunderstanding what a service is, or is the whole thing just wired
    >wrong?


    The Equitech isolates the input and output lines, SO the neutral wire on
    the input has no connection to the neutral wire on the output.

    This means that the ground on the input doesn't need to be connected to
    the ground on the output either, and you can have a seperate ground for
    the circuits on the other side of the isolation transformer, and lift the
    ground on the line from the main service panel to the isolation transformer.

    This is the big deal about isolation transformers, that you are now totally
    separated from the grounding system in the rest of the building. So everything
    on the secondary is like having a different service altogether.

    >I am starting to wonder if maybe I shouldn't wait for this electrician
    >to get back to work, but should instead call someone else, and get a
    >second pair of eyes on it...


    If I were you, I'd call a lightning protection company. Find out who your
    local Staticat dealer is and talk to them.
    --scott
    --
    "C'est un Nagra. C'est suisse, et tres, tres precis."
  10. Jay Levitt

    Jay Levitt Guest

    In article <bh0u56$5g4$1@panix2.panix.com>, kludge@panix.com says...
    > The Equitech isolates the input and output lines, SO the neutral wire on
    > the input has no connection to the neutral wire on the output.


    Right.. and in fact the neutral isn't even neutral anymore, being
    balanced power. (If you get electrocuted by a negative voltage, does it
    make you more alive?)

    > This means that the ground on the input doesn't need to be connected to
    > the ground on the output either, and you can have a seperate ground for
    > the circuits on the other side of the isolation transformer, and lift the
    > ground on the line from the main service panel to the isolation transformer.


    AH! Because, as I always forget, the neutral and ground are actually
    (normally) tied together, so you can't cascade the neutral but have a
    separate ground. I think I see now.

    I'm so glad I went into software. I still don't quite follow how all
    the little minus signs get over to the big plus sign...

    --
    Jay Levitt |
    Wellesley, MA | Hi!
    Faster: jay at jay dot eff-em | Where are we going?
    http://www.jay.fm | Why am I in this handbasket?
  11. Dale Farmer

    Dale Farmer Guest

    "Roger W. Norman" wrote:

    > And that's why I am taking the electrical and re-doing it, which, of course,
    > puts the patio thing on a slower track because I have to carefully dig up
    > all that 6/2 UFB cable and re-do the circuits without touching the shell of
    > the pool. Admittedly, a non conducting mouting surface, outdoor
    > weatherproofed boxes, GFI breakered power and a properly run 8' #6 ground
    > rod should do the job, but not the way NEC states the job should be done.
    >
    > Looks like I won't get this yard done until we're into the fall, dammit. Oh
    > well, maybe we'll get a couple of bushels of crabs and have a crab feast
    > instead. Who the hell wants to party in the heat of August with a pool and
    > A/C going in the studio? <g>
    >
    > Of course, if you want to stop by and help on one of your weekends up here,
    > I'll be glad to provide all the comforts like meals, beers, a swim in the
    > pool, bathtub spa (if you need it). Know anything about doing brick mason
    > work or even how to mix mortar to the right consistency? <g>


    room temperature peanut butter. Leave no voids in the mortar. When your
    mortar starts to get stiff, toss it and mix a fresh batch. Don't work too
    fast
    for the mortar. If you go too fast the still wet mortar below gets squeezed out

    by the weight of the bricks above and the whole structure starts to tilt. Take
    your time, check your level *every* course of bricks. Don't forget to tie the
    face bricks to the inner layers of the wall/chimney. Use bricks that are outdoor

    rated for outdoor structures. Make your foundation stronger than you think
    it needs to be. Much stronger, the Building Code is the minimum, not the
    best.
    ( I was a masons helper when I was a teenager, on the houses that my
    grandfather built... as well as carpenter's helper, electricians helper,
    cleanup
    guy and go get lunch guy. One of the happiest day of my younger life was
    when my granddad finally broke down and bought a power saw. )
  12. Dale Farmer

    Dale Farmer Guest

    Scott Dorsey wrote:

    > Jay Levitt <jay+news@jay.fm> wrote:
    > >In article <bh08f7$kv2$1@bob.news.rcn.net>, rnorman@starpower.net
    > >says...
    > >> A subpanel SHOULD NOT be running to a separate ground. The ground runs back
    > >> from the subpanel to the service or it's a real, separate service. A new
    > >> service needs grounding. A subpanel should not be grounded. 70 Amps
    > >> requires 6/2 cable for anything less than 150 feet, so your Equitech panel
    > >> is indeed a new service and needs to have it's own ground.

    > >
    > >I'm confused. I thought a "new service" means that it's actually a
    > >parallel feed from the street - e.g. right now I have two 200-amp
    > >services going to two main panels (with two big shutoffs outside).

    >
    > Right.
    >
    > >But
    > >the Equitech is hanging off a 70A breaker in a subpanel, as depicted in
    > >my stunningly aesthetic diagram elsewhere in this thread.. am I
    > >misunderstanding what a service is, or is the whole thing just wired
    > >wrong?

    >
    > The Equitech isolates the input and output lines, SO the neutral wire on
    > the input has no connection to the neutral wire on the output.
    >
    > This means that the ground on the input doesn't need to be connected to
    > the ground on the output either, and you can have a seperate ground for
    > the circuits on the other side of the isolation transformer, and lift the
    > ground on the line from the main service panel to the isolation transformer.
    >
    > This is the big deal about isolation transformers, that you are now totally
    > separated from the grounding system in the rest of the building. So everything
    > on the secondary is like having a different service altogether.
    >
    > >I am starting to wonder if maybe I shouldn't wait for this electrician
    > >to get back to work, but should instead call someone else, and get a
    > >second pair of eyes on it...

    >
    > If I were you, I'd call a lightning protection company. Find out who your
    > local Staticat dealer is and talk to them.
    > --scott


    You are getting into 'Separately derived service' I think the phrase is.
    It is touched on in a couple of the NEC chapters. Go and read some more.

    --Dale
  13. Dale Farmer

    Dale Farmer Guest

    "Roger W. Norman" wrote:

    > You don't ground a subpanel unless you are effectively making it another
    > service. Technically, what I did (run a 60 amp circuit to the woodshop
    > subpanel with a grounding rod) causes that to be another service, but code
    > wise there should be another run of electrical from the street to that panel
    > to create a new service. So not having the grounding braid from both panels
    > is incorrect in your situation.
    >
    > Most likely your grounding braid simply ties to a grounding rod in the crawl
    > space. Of course, you can always pull on the damned thing and see if it's
    > hooked up to anything. But you seriously need to have your electrician look
    > at the grounding and get it fixed, if what you report is correct.
    >
    > --
    >
    > Roger W. Norman
    > SirMusic Studio
    > Roger@SirMusicStudio.com
    > 301-585-4681


    If you have two service entrance panels in the building, and their ground
    rods
    are not close to each other, then you probably have some voltage present between

    the two ground references. I've personally see 30 volts difference in a hotel
    ballroom, where the stage power came from one end onf the building, and the
    wall plugs up on the balcony came from another end of the building. I've heard
    tell of larger differences.
    So if your PC in your bedroom is on the house panel, and the signal cable
    to the mixer in the studio plugged into the other panel, may be causing a huge
    ground loop on that signal wire. This is speculation, of course.

    --Dale
  14. Ah, somewhat akin to me being pleased that, as a plumber's helper, we
    finally got a power threader for gas pipe. Spent a year on gas piping
    alone.

    Good tips on the mason stuff, but I've been working alone, so there's really
    no time to let mortar sit. I make it, go get the next corse of blocks, mud
    it and do it again. Luckily it's just a retaining wall, so if it leaned,
    and did so in the direction of the higher level of dirt, that wouldn't be
    too bad. But so far so good. I'll be doing the facing with brick and can
    start that pretty soon. Then it's truckloads of dirt and gravel, make about
    80 more concrete pavers (that's the one that hurts the back), one 60 lbs bag
    per mould, wait an hour, do it again (and I have four moulds). I still have
    3,000 lbs of concrete to move up out of the driveway - by myself. What's
    the use in having kids?

    BTW, I check level on every block. Although I don't trust NOT doing so, so
    far each corse has been correct.

    --


    Roger W. Norman
    SirMusic Studio
    Roger@SirMusicStudio.com
    301-585-4681




    "Dale Farmer" <Dale@cybercom.net> wrote in message
    news:3F34863D.341BE938@cybercom.net...
    >
    >
    > "Roger W. Norman" wrote:
    >
    > > And that's why I am taking the electrical and re-doing it, which, of

    course,
    > > puts the patio thing on a slower track because I have to carefully dig

    up
    > > all that 6/2 UFB cable and re-do the circuits without touching the shell

    of
    > > the pool. Admittedly, a non conducting mouting surface, outdoor
    > > weatherproofed boxes, GFI breakered power and a properly run 8' #6

    ground
    > > rod should do the job, but not the way NEC states the job should be

    done.
    > >
    > > Looks like I won't get this yard done until we're into the fall, dammit.

    Oh
    > > well, maybe we'll get a couple of bushels of crabs and have a crab feast
    > > instead. Who the hell wants to party in the heat of August with a pool

    and
    > > A/C going in the studio? <g>
    > >
    > > Of course, if you want to stop by and help on one of your weekends up

    here,
    > > I'll be glad to provide all the comforts like meals, beers, a swim in

    the
    > > pool, bathtub spa (if you need it). Know anything about doing brick

    mason
    > > work or even how to mix mortar to the right consistency? <g>

    >
    > room temperature peanut butter. Leave no voids in the mortar. When

    your
    > mortar starts to get stiff, toss it and mix a fresh batch. Don't work

    too
    > fast
    > for the mortar. If you go too fast the still wet mortar below gets

    squeezed out
    >
    > by the weight of the bricks above and the whole structure starts to tilt.

    Take
    > your time, check your level *every* course of bricks. Don't forget to tie

    the
    > face bricks to the inner layers of the wall/chimney. Use bricks that are

    outdoor
    >
    > rated for outdoor structures. Make your foundation stronger than you

    think
    > it needs to be. Much stronger, the Building Code is the minimum, not the
    > best.
    > ( I was a masons helper when I was a teenager, on the houses that my
    > grandfather built... as well as carpenter's helper, electricians helper,
    > cleanup
    > guy and go get lunch guy. One of the happiest day of my younger life was
    > when my granddad finally broke down and bought a power saw. )
    >
  15. Re: Lightning surges

    On Wed, 6 Aug 2003 09:44:19 -0400, someone who calls themselves "Roger
    W. Norman" <rnorman@starpower.net> wrote:

    >There are arc triggered breakers that see a "serious" drain on a system,
    >like a unit frying, and do their job of breaking. Simple replacements for
    >the panel, and although I think it would work for outside events, it's
    >principally designed to stop arc from dangerous internal circuits. I don't
    >know what it would do if it saw too much current coming in.
    >


    I know I'm late on this (this newsgroup is like getting a drink out
    of a firehose), but an Arc Fault circuit breaker won't work for
    lightning strikes.

    The AFCI is looking for arc effects on the Load side that you would
    get from a Romex staple pinch inside the wall (possibly causing a
    smouldering fire inside the wall) or a bad appliance cord to trip the
    breaker - a few thousand volts coming in the Line side from a
    lightning strike will just fry the whole thing....

    --<< Bruce >>--
    --
    Bruce L. Bergman, POB 394, Woodland Hills CA 91365, USA
    Electrician, Westend Electric (#726700) Agoura, CA

    WARNING: UCE Spam E-mail is not welcome here. I report violators.
    SpamBlock In Use - Remove the "Python" with a "net" to E-Mail.
  16. Re: Lightning surges

    On Wed, 06 Aug 2003 18:38:08 -0500, Chris Hornbeck
    <guyville@removethisaristotle.net> wrote:

    > Looking at a list of insulators,
    >puncture voltage expressed in volts per mil (.001") varies from
    >40 (porcelain!?) to 5600 (mica). Air is listed with no value
    >given.


    Found a later listing of 21 volts per mil for "air". Still
    no idea what "air" means or how the numbers scale. I'd be
    very surprised if it were linearly.

    Chris Hornbeck
    http://www.votetoimpeach.org/
  17. Jay Levitt

    Jay Levitt Guest

    Re: Lightning surges

    In article <pd57kvsp019gnt1q91sq7s23v3t34p3vum@4ax.com>,
    guyville@removethisaristotle.net says...
    > Found a later listing of 21 volts per mil for "air". Still
    > no idea what "air" means


    Boost @ 16KHz. HTH...

    --
    Jay Levitt |
    Wellesley, MA | Hi!
    Faster: jay at jay dot eff-em | Where are we going?
    http://www.jay.fm | Why am I in this handbasket?
  18. Glenn Davis

    Glenn Davis Guest

    Re: Lightning surges

    > I know I'm late on this (this newsgroup is like getting a drink out
    >of a firehose),


    Agreed. Also, this is one of those threads that shows up on my list like this:

    RE: Lightning
    RE: Lightning
    RE: Lightning
    How do I rebuild SSL Power Supplies?
    Advantages of an "Aircraft Carrier Size Console"
    RE: Lightning
    RE: Lightning
    Question about mixing
    Help, My Cat Pissed On My Tapes!
    Baking Old Tapes 101
    RE: Lightning
    RE: Lightning
    The State Of The Music/Recording Industry
    Why mixing with real faders instead of a mouse is better
    I can't get my tools software to stop crashing!
    RE:Lightning

    So it is not as easy to keep on the subject. One thing that is of concern with
    Lightning is having it "Scramble" certain Electronics. You can even fuck things
    up by just turning things on. Without getting into a several page spew of
    techno-babble about Reset Circuit Design, Schmitt Trigger, 555 Timer and the
    like, there are several things to look for and do. If you have a memory glitch
    problem in let's say for sake of argument your keyboard, you can reset the RAM
    by shorting the backup-battery voltage to ground for a moment. A ground-shunt
    lead is what you need. You can construct one from an old test probe, a resistor
    and alligator clip. A real common failure is in standard IC-regulator-type
    power supplies when there is a damaged or open rectifier diode in the raw-DC
    input section. Often, a line transient will exceed the surge current or Peak
    Inverse Voltage capacity of the diode and destroy it. You can often just
    replace the diode, but you should check close by components for damage too.
    Electrolytic caps are vulnerable; check for signs of arcing or discolored PC
    pads and solder joints and check radial caps for distention of the vinyl top
    cover. Things like old 7805 IC Regulators rarely fail due to built in thermal
    and current overload protection.

    Glenn Davis
    "Creating the perfect mix is like painting a 747 with Q-Tips"
  19. Rob Reedijk

    Rob Reedijk Guest

    Re: Lightning surges

    Here in Canada they are starting to force us to put in AFCIs. Last
    year in Ontario we had to put them in for all sleeping areas (new
    installations). It is expected that within a few years ALL circuits
    will require them (and hopefully the price will come down from the
    $80 CAD per breaker!)

    So, the cost-cutting measure that I have even heard recommended by the
    Electrical Safety Authority, is to go back to rooms sharing circuits,
    which is not a good thing.

    Is this happening in the States, too?

    Rob R.

    Bruce L. Bergman <blPYTHONbergman@earthlink.invalid> wrote:

    > I know I'm late on this (this newsgroup is like getting a drink out
    > of a firehose), but an Arc Fault circuit breaker won't work for
    > lightning strikes.


    > The AFCI is looking for arc effects on the Load side that you would
    > get from a Romex staple pinch inside the wall (possibly causing a
    > smouldering fire inside the wall) or a bad appliance cord to trip the
    > breaker - a few thousand volts coming in the Line side from a
    > lightning strike will just fry the whole thing....
  20. Re: Lightning surges

    On 21 Aug 2003 18:19:01 GMT, someone who calls themselves Rob Reedijk
    <reedijk@hera.med.utoronto.ca> wrote:
    >Bruce L. Bergman <blPYTHONbergman@earthlink.invalid> wrote:


    >> I know I'm late on this (this newsgroup is like getting a drink out
    >> of a firehose), but an Arc Fault circuit breaker won't work for
    >> lightning strikes.

    >
    >> The AFCI is looking for arc effects on the Load side that you would
    >> get from a Romex staple pinch inside the wall (possibly causing a
    >> smouldering fire inside the wall) or a bad appliance cord to trip the
    >> breaker - a few thousand volts coming in the Line side from a
    >> lightning strike will just fry the whole thing....

    >
    >Here in Canada they are starting to force us to put in AFCIs. Last
    >year in Ontario we had to put them in for all sleeping areas (new
    >installations). It is expected that within a few years ALL circuits
    >will require them (and hopefully the price will come down from the
    >$80 CAD per breaker!)


    They're around $45 Real US Dollars in Los Angeles, which would put
    them at about $60 Funny Canadian Dollars, any more than that is duties
    & tariffs or the retailer taking advantage of more markup in a less
    competitive area...

    >So, the cost-cutting measure that I have even heard recommended by the
    >Electrical Safety Authority, is to go back to rooms sharing circuits,
    >which is not a good thing.


    No, it's perfectly legal to share a receptacle circuit between
    multiple rooms, as long as you hold the loading down - it's something
    like 10 receptacles on a 15A circuit and 15 on a 20A, but I haven't
    needed to rope in any new construction in a /long/ time...

    And when I do I'm usually very conservative on the circuit loading
    anyways. A little extra wire and a few extra breakers are a lot
    cheaper than reworking it all later because of a loading problem...

    >Is this happening in the States, too?


    Soon, but not yet. The breakers are just getting on the market.

    ==<< Bruce >>--
    --
    Bruce L. Bergman, POB 394, Woodland Hills CA 91365, USA
    Electrician, Westend Electric (#726700) Agoura, CA

    WARNING: UCE Spam E-mail is not welcome here. I report violators.
    SpamBlock In Use - Remove the "Python" with a "net" to E-Mail.

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