Grounding Do's Don'ts & Why Part 3

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by KF5LJW, Mar 19, 2012.

ad: L-HROutlet
ad: l-rl
ad: Subscribe
ad: Left-2
ad: MessiPaoloni-1
ad: L-MFJ
  1. W3ICM

    W3ICM Ham Member QRZ Page

    Dereck, excellent thread with an enormous amount of information.
    I am reading the 2017 ARRL book by Ward Silver, N0AX, "Grounding and Bonding for the Radio Amateur."
    The thread has much more in advising on individual cases.

    There is some mention in the thread of RF tripping GFCIs (also called Ground Fault Interrupt of GFI). I am only running 100 watts to a G5RV, and I may be tripping some GFCI. I have three that just wont reset. I tested them with a ground and outlet tester, and two of them show an "open hot."

    I don't know if the GFCI socket is damaged and needs replacing.

    Would appreciate your advice.

    I would also like comments on the ARRL book. It's the first book of its kind, and it has a great deal of information that was not published before; or published in one place.
     
  2. N6OPS

    N6OPS Ham Member QRZ Page

    Well Said ! You should pay attention to Dereck on this one. His refrences are in cost under 500.00 from Tessco.
    It might save your life, or someone you love. You need to get the lightning away from you. Remember an antenna is a path lighning is looking for ground on. If you are inbetween this, Well, I hope your ready to go... further refrence is Motorola R56 standard.
     
  3. N6OPS

    N6OPS Ham Member QRZ Page

  4. KF5LJW

    KF5LJW Ham Member QRZ Page

    Well if the Line (aka Hot as you call it is open), then there is no power. Same thing as an Off switch, no power. Now if you cannot reset the GFCI, then it will not have any power as designed. My bet is you have old GFCI in need of replacement.

    Not uncommon for GFCI breakers to trip when exposed to high amounts of RF power. Cause is mostly RFI circuits (capacitors) installed in equipment between L-G and N-G. Blame that on equipment manufactures taking shortcuts to meet FCC requirements.


    Have not read it. All my advice falls in line with all known best practices from standards like Motorola R56 which is way outdated, Milt Std, Telco, CATV, Commercial Broadcast, and other sources related to the industry which all meet or exceed minimum NEC requirements. It is impossible for me to cover all applications.

    Here is the big picture to sum it up.

    Bond everything in Dirt and outside together. Bond everything Inside together. Bond the two together at ONE SINGLE POINT only.
     
  5. W3ICM

    W3ICM Ham Member QRZ Page

    I started a new thread on the GFCI tripping. There are many interesting posts to the thread/
     
  6. KG5WKO

    KG5WKO Ham Member QRZ Page

    I followed your advice, Each mast is grounded and tied together with #6 if my memory is right and then to station ground and then to utility ground. I used insulated solid copper on wire and hope not wrong but less expensive.(buried) All three bonded. Local utility men were great help. They put in a ground and conduit from my station ground where it comes to to their ground at no cost!
     
  7. KF5LJW

    KF5LJW Ham Member QRZ Page

    Not wrong, and complies with code, but not optimal. Radials are more effective than ground rods with respect to lightning. Using insulated defeated optimal installation practice.

    So how is the noise floor on your RX?
     
  8. W9XMT

    W9XMT Ham Member QRZ Page

    Observations:

    Medium-wave AM broadcast stations typically use an r-f ground path through a set of 120 x 1/4-wavelength, uninsulated conductors buried radially in the earth, with their common point located directly below the base of their (monopole) radiators. They also use a series-connected arc gap between the tower base and and one or more ground rods buried near the tower base. The gap spacing is set to flash over when the radiator base voltage exceeds the normal value for the modulated peak power at the feedpoint, by a given amount. Also the tower base is connected directly to the ground rod(s) through an r-f choke at the operating frequency, to avoid d-c (static) buildup voltages on the tower.

    Even though their vertical radiators can approach heights of 1,000 feet AGL, such AM broadcast stations continue to operate during nearby lightning events without component damage(s), and without loss of service except for the very short (x-millisecond) intervals when the arc gap flashes over, because protection circuits in their transmitter sense the arc event and kill their r-f output for that time interval.
     
  9. KD5NDQ

    KD5NDQ Ham Member QRZ Page

    Dereck, first off - thank you for these 3 stickies and all the subsequent replies tempered with amazing patience to answering all these questions (I read every post and reply!) - my hat's off to you, sir!

    Now I am ready to practice what you have been preaching. I have a ground rod next to where my feedlines come into the basement shack that I intend to attach feedlines to. The rod is leftover I think from when previous homeowners had satellite TV and the coax from roof was attached to it. It is not bonded to the electrical service ground as near as I can tell, and they are on opposite sides of the house. So, if I have understood all of your posts, I need to run #6 solid copper from this ground rod to the one at the electrical service entrance.

    1) The distance between the 2 rods is probably 75 - 100' and has to traverse a concrete sidewalk and patio next to the house where the service ground is located. I could get it to the service ground if I attach the last 5' or so to the house and then not have to break up any concrete. Is this acceptable?

    2) There is a copper piped cold water faucet coming out of the basement much closer than the service ground. Would this be an acceptable substitute to connect to instead if I can verify the pipes are grounded with the service ground? If so, how do I verify this?

    3) (Biggee and afraid to ask) How do I verify in this 40 year old house the service ground is actually "ground" the way it is supposed to be? Can I verify this and #2 above with a VOM?

    Thanks again
    Bob
    KD5NDQ
     
  10. KD0CAC

    KD0CAC Ham Member QRZ Page

    Good time to thank Dereck also - thanks , me too ;)

    Bob , haven't read every post , but have read many & others also , and the Motorola's document , have a copy on DVD , what G-56 or close .
    On outside of house / shack , my general understanding is , you're trying to create something like a Faraday cage / skin separating inside-outside .
    As I picture your description [ and did not read that you found the electrical service entrance for AC power into house ?
    So guessing that the satellite & service entrance maybe on different walls ?
    So I would make a ring around the house [ as apposed to a single wire - to avoid any outside electrical energy - seeing the single wire as a antenna = Faraday cage ] and then attach both ground rods to the new loop of wire , what you doing is 3 fold 1st making that cage , 2nd connecting all grounds together - to bring all wiring to the same potential / or lack of , 3rd now no matter where you coax enters the house / shack - you have access to a ground wire - the closed loop .
    As to where that new outside loop is , its hard to say with seeing , but with the sidewalk up against the foundation , you could leave the wire-loop in the seam where the walk & wall meet , and use some type of cement silicone to help hold in place , or some hairpin shaped copper [ copper to avoid dissimilar metal issues ] hammered in seam , you could also do the same if needed with crossing the sidewalk in seam .
    I there is any sizable gap between foundation & sidewalk - I have used garden hose , water-drill , to go under sidewalks & driveways , using the water pressure to cut hole through ground under walk / drive , sometimes if needed tapping wire to hose to make corners in water-drill .
    One of the issues with ham radio grounding is the need for operating during & surviving a direct hit , the commercial places can & do without issue - BUT it costs lots of money in parts & labor , so your situation - how much operating & how much money , somewhat depends on the frequency of lightning & you $ & operating , where to make choices .
     

Share This Page