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Feedback please: Homebrew grounding system


W3ESX
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Hello,

After having spoke with several seasoned hams about my setup, I've come to the conclusion that I need a grounding system for my rigs and antennas for safety purposes. For the past few days I've been doing some research and I've come up with a system that I think will work and will last, but I have some questions and I would like some feedback. Thanks in advance!

Summary

Basically, I want to:

  1. drive a new 8' long (5/8" diameter) ground rod on the side of my house,
  2. fasten a 1" width copper strap onto the rod (using a clamp) and run it up the siding of my house and into an enclosure (details to follow),
  3. fasten the copper strap to a grounding bar within the enclosure, which also has lightning arresters mounted to it
  4. mount the enclosure to the side of the house and run the coax into the enclosure, through the arresters, and then back out into my shack via a passthru panel

Enclosure

From my research, I think a simple AC disconnect box will serve as a great enclosure. I will of course rip out all of the guts that I don't need. I will use the existing punch-outs to create ingress/egress for the coax, with clamp-downs (my electrician terminology is weak, I know 😆) to hold the cables in place internally. I have some moldable non-adhesive sealant that will go around the ingress and egress points to waterproof them.

The grounding bar in the enclosure as-is is pretty small and the arresters are pretty bulky, so I think I will need to buy a new one. However, none that I've found on DX Engineering or HRO have been the right size (they are usually 10+" long and the box is 7" long). Any tips on a good one to purchase? I don't need a big one because at this QTH I will likely not be able to have more than the 2 antennas I already have (well, one operational, one planned).

Materials

This is pretty much everything I think I will need for the project:

Questions
I have the following questions:

  1. Which do you think would be a better setup: having the enclosure mounted high up near the antenna (shorter coax runs, longer ground strap runs) or low down near the grounding rod (longer coax runs, super short ground strap runs)? I'm leaning towards the latter because RG-8X is pretty cheap, and copper is expensive.
  2. What product(s) are recommended to serve as the "raceway" for the copper strap and/or coax from the enclosure to the grounding rod? Needs to be mountable to standard vinyl siding with minimal damage, and of course weather-resistant. Thinking D-channel, but haven't found any that is specifically listed as being outdoor-safe. Also has to be pretty wide diameter, as depending on the setup I may want to also run the coax through it along with the grounding strap.
    1. (Is it safe to run the grounding strap parallel to the coax? Is it safe to run the pre-arrester and post-arrester coax lines parallel to one another?)
  3. Any other red flags from reading my plan, either safety-wise or code-wise? I do not live in an HOA (thank goodness) but want to maintain code adherence wherever possible to avoid damaging value of home (and pissing off XYL).

😍👽😺 === Thanks!!! ===  😍👽😺 

I am open to any and all (constructive) feedback and am happy to engage in discussion or answer any clarifying questions.

73 DE W3ESX

 

 

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ELMER

Hi Jamison. Read the post, now I want to visualize and digest for a couple of hours. Minor first jump-off-the-page, I know you want to save, but you can do better than RG-8X and for this level of effort, I would. Another mini orange flag is your raceway. Careful not to build something that ultimately causes condensation. Weather-resistant yes, weather-proof, so to speak, no. My personal preference is to leave the copper exposed. As for the coax, if you get a good outdoor coax, as in the LMR-400 range, even the one that's meant for underground burial (Times Microwave LMR-400 Direct Burial Coaxial Cable - Black) or even the normal one, you won't need to protect it either. Maybe, just to give it a 'blending look' on the side of the house, you can get a long roll of 'house colored' heat shrink and camouflage it that way.

I hope I'm visualizing your setup correctly...

The real question, and it's a good one that deserves some thought, is the height of the box. I would mount it low, not to save on copper, but to have any current travel less distance to ground. I would not, however, allow for any parallel running. My setup has the ground wire moving away from the coax at 90-degrees in the hope that the current does not decide to travel along with the coax.

Last point about the box... I'm repeating what I said above... condensation!!! Make sure your box is very very very well vented.

Last little thought as per XYL and house value. One thing I had done for a friend is to build everything into runs of PVC pipe which were a couple of inches away from the wall of the house and simply fastened with three brackets (top/middle/bottom). We had then painted the PVC in the same color as the house. Basically invisible. Just a thought.

Hope this kinda/sorta helps.

Jim

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K3MRI, thank you for the detailed response!

Regarding the coax, I agree I could be doing better than 8X, but it's triple the price and I already have a ton of other stuff to buy...considering an incremental upgrade here, e.g. use the 8X I have now, and swap out for LMR-400 if I find a bunch on sale at a hamfest or some such. The advice of using higher-quality cable for the effort is heard and appreciated, though.

Sounds like you are recommending what I am calling Option B for the enclosure mounting, which is close to the ground. That's good, because that's the one I think I like better, too. Means longer coax runs and shorter ground strap runs. I'm OK with that, especially if it maximizes safety by shortening the path to ground.

I will have to do some thinking on the best way to route the cables down the siding and to the enclosure, especially because I also want to run a grounding wire from the passthru panel into the enclosure and, as you recommended, it should be orthogonal to the coax runs. PVC sounds like a great idea, I can get grey plastic conduit from Home Depot for nothing at all.

Thanks again for the idea vetting and advice. I will probably be doing up some diagrams shortly to aid in visualization, which I will post on this thread.

73 de W3ESX

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1176905403_GroundingSystemSketch-v1.jpeg.1f75d3517a27ed7d92569858d0c980bd.jpeg

Here is my initial diagram of the grounding system, mounted low to the ground as @K3MRI recommended. The diagram leaves a little to be desired, but it's a rough sketch so I'm OK with that.

The primary problem I'm struggling with at the moment is how to get a grounding strap from the passthru panel in the window down to the GND unit in the least-obvious way possible. I a) don't want it to drape over the window (the shutters are screwed to the house, so can't go behind them, sadly) and b) am worried about all the 90º turns that would have to be made to route it around all the windows and other items.

Any advice is welcome. I have started purchasing some of the parts for this that I know I will need, including a 40" mast that I am very excited to put up.

73 de W3ESX

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ELMER

Hi Jamison.

Oooops. Hold on.

First, great diagram. Would have been super helpful to better understand. My bad earlier.

Wrong approach... Don't shoot 😎

First a question which I should have asked earlier: HF or VHF/UHF? Also, in case I missed it, what type of coax? I ask these two because of signal loss. Based on this diagram, and the fact that you are upstairs, that ground unit has to go up up up and you have to run your grounding wire from upstairs to the ground. This will give you multiple benefits including much less coax.

I'll wait for your answer, but basically, I had not realized your shack was on the second floor.

😇

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No worries at all. Truthfully, I needed to write all that out in order to picture it in my head properly so as to create the diagram. So you are in the clear hi hi!

There will be two antennas run into this system: one dual-band UHF/VHF via a 10' Diamond vertical, the other a multi-band HF via a Chameleon EMCOMM III wire sloper. The coax lines for these two will run in parallel (the red and the blue in the diagram) first down to the grounding system, then back up to the passthru panel.

As for type of coax, I was originally going to try to use the RG-8X I had on hand, but I will likely need custom lengths anyways now that I have this diagram so I will most likely go ahead and make the jump to LMR-400 (as you recommended) for the better resiliency/signal quality.

The way I see it, I have two grounding solutions I need to figure out here:

  1. The coax lines from the antennas need to be run through lightning arresters contained in the box at ground level
  2. I need to run a grounding wire from the passthru panel down to the grounding box at ground level as well

I'm pretty confident on my solution for the former, but not as much so for the latter. Any advice welcome.

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ELMER

Here's my issue. A lightning arrester should be located as close as possible to the equipment that it is expected to protect. In large substations, for instance, arrestors are installed at take-off points of the lines and of the terminal apparatus. Also, it is good practice to have the arrester as close to the point of ingress of a coax into a building. Put those two together and being on the second floor, you have many good reasons to have the arrestors up high.

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10 minutes ago, K3MRI said:

Here's my issue. A lightning arrester should be located as close as possible to the equipment that it is expected to protect. In large substations, for instance, arrestors are installed at take-off points of the lines and of the terminal apparatus. Also, it is good practice to have the arrester as close to the point of ingress of a coax into a building. Put those two together and being on the second floor, you have many good reasons to have the arrestors up high.

Ah, I see! That could simplify the system a great deal, which would also save me some money.

So, based on this, I would put the lightning arresters directly on the passthru panel, i.e. with one side being fed by the coax from the antenna and the other side screwed directly into the coax ports on the passthru panel. I assume those ports are grounded to the GND terminal on the panel. (Is that a safe assumption?) All I would have to do then is bond the ground connections of the two lightning arresters to the ground strap coming out of the ground port, and then bond all of that down to the ground rod.

See below for reference of the passthru panel I am using:

image.png.3ae29c3c2f8ac4568266bd810beb81de.png

And here is the lightning arresters I intend to use:

image.png.c9eabf00126284c8d15ec386dc1fc9c3.png

Would all of this make for a better system? If I am understanding you correctly, this would save me a ton of coax, which can do nothing but good things for signal quality.

Edited by W3ESX
Add image of lightning arrester
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ELMER

My answer: ✌️😇

Yes to almost all. I'm going to say that it seems like a good idea to connect the arrester directly to the panel with a double barrel (male-male) but I've never done it. I've always added a very very short run of cable, as in inches. Why you ask? My lame excuse is because that's how my dad did it but frankly, why inject another few points of db loss in the connectors. Just make sure your barrel is of high quality and remember that there will be, ever so little of course, but there will be a little bit of 90-degree strain on that connection; which is why, I'm guessing, my dad added the little bit of cable. In his case, it was always today's equivalent of hardline. Again, not sure that it's necessary.

Looking forward to seeing photos of the finished project.

PS. Yes, safe assumption that the outer part of the SO is grounded to the chassis but, being stupidly overzealous, a nice little ohmmeter moment and beep would never hurt. But yes, they're connected (he says).

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15 minutes ago, K3MRI said:

My answer: ✌️😇

Yes to almost all. I'm going to say that it seems like a good idea to connect the arrester directly to the panel with a double barrel (male-male) but I've never done it. I've always added a very very short run of cable, as in inches. Why you ask? My lame excuse is because that's how my dad did it but frankly, why inject another few points of db loss in the connectors. Just make sure your barrel is of high quality and remember that there will be, ever so little of course, but there will be a little bit of 90-degree strain on that connection; which is why, I'm guessing, my dad added the little bit of cable. In his case, it was always today's equivalent of hardline. Again, not sure that it's necessary.

Looking forward to seeing photos of the finished project.

PS. Yes, safe assumption that the outer part of the SO is grounded to the chassis but, being stupidly overzealous, a nice little ohmmeter moment and beep would never hurt. But yes, they're connected (he says).

Excellent. I will get those orders placed for the passthru panel, the lightning arresters, some LMR-400, and some adapters and we will see where we stand.

Thanks for all the advice!

W3ESX OUT!

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ELMER
On 8/24/2021 at 2:18 PM, W3ESX said:

Excellent. I will get those orders placed for the pass-through panel, the lightning arresters, some LMR-400, and some adapters and we will see where we stand.

Thanks for all the advice!

W3ESX OUT!

Jameson W3ESX

First let me introduce myself and provide a little of my background. I'm retired out of over 45 years in the electrical craft. I spent a part of my career installing communications shelters from Tierra Del Fuego up to Alaska and from French Frigate Shoals to Tucson Arizona area. The number of shelters I managed the installation of is over 100. The most important part of the installations was usually the Grounding Electrode System. Many of the shelters which I oversaw were self contained and self powered. Since that doesn't bear on your project I'll leave it there.

A Ground Rod is a Grounding Electrode. Three Driven Rod Electrodes spaced 2X their length apart, bonded to each other, and then connected to a Ground Busbar or cable entry bulkhead is a Grounding Electrode System. This leads to several questions.

Were is your Electrical Meter and Service Equipment in Relation to the Antenna entry? Is it on the end of the house shown in the diagram or is it on the other end.

Is there any particular reason that you want to use a steel enclosure for your lightning arresters?

Will any other wire of any description enter your home through your grounding bulkhead. (That is the conductive metal panel of grounding busbar were you will be mounting your arresters.)

I ask these question because the answers have a large effect on the effectiveness of your grounding system.

--

Tom Horne W3TDH

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10 minutes ago, W3TDH said:

Jameson W3ESX

First let me introduce myself and provide a little of my background. I'm retired out of over 45 years in the electrical craft. I spent a part of my career installing communications shelters from Tierra Del Fuego up to Alaska and from French Frigate Shoals to Tucson Arizona area. The number of shelters I managed the installation of is over 100. The most important part of the installations was usually the Grounding Electrode System. Many of the shelters which I oversaw were self contained and self powered. Since that doesn't bear on your project I'll leave it there.

A Ground Rod is a Grounding Electrode. Three Driven Rod Electrodes spaced 2X their length apart, bonded to each other, and then connected to a Ground Busbar or cable entry bulkhead is a Grounding Electrode System. This leads to several questions.

Were is your Electrical Meter and Service Equipment in Relation to the Antenna entry? Is it on the end of the house shown in the diagram or is it on the other end.

Is there any particular reason that you want to use a steel enclosure for your lightning arresters?

Will any other wire of any description enter your home through your grounding bulkhead. (That is the conductive metal panel of grounding busbar were you will be mounting your arresters.)

I ask these question because the answers have a large effect on the effectiveness of your grounding system.

--

Tom Horne W3TDH

Tom,

We actually know each other! I was a member of MARC (you knew me then as KC3HKF) before I moved out to Baltimore and then to Detroit. We are back on the east coast now, and own a house up in Essex. I'm slightly out of the range of KV3B repeater, but that's one of the problems I'm hoping to correct by setting up this antenna.

Sadly, the electrical meter and service equipment is on the exact OPPOSITE side of the house as my shack. That is why I intended to drive another grounding bar. I hadn't originally thought that I would need to bond the two grounding bars together, but as I'm reading more of Grounding and Bonding for the Radio Amateur, it does appear that I should do that for safety's sake and to ensure common voltage.

As for the steel enclosure, no I had no particular reason for picking that other than that I saw a YouTube video with someone building a fully self-contained box with the lightning arresters and an internal ground bar and I quite liked the convenience and compactness of that design. This is the video. Are there any reasons NOT to use the steel enclosure that I am not considering? I will be the first to admit my electrical knowledge is lacking, but I am working to improve it.

As of this moment, the only wire that will be entering my home through the grounding system will be the coax. The coax will come down from the antenna, into the lightning arresters inside the box, and then coax coming out the other end of the arresters will go back up into my shack through a passthru panel. There is an additional "dedicated ground lug" on the passthru panel that I want to use that I will likely drop down from the panel and bond directly to the ground rod, but I'm taking it one step at a time.

Hopefully this clarifies some things.

Thanks,

Jamison W3ESX

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ELMER

FINALLY, a true expert in the field. @W3ESX you could not be in better hands than @W3TDH. I cede 😇

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  • Elmers
ELMER
On 8/26/2021 at 2:52 PM, W3ESX said:

Sadly, the electrical meter and service equipment is on the exact OPPOSITE side of the house as my shack. That is why I intended to drive another grounding bar. I hadn't originally thought that I would need to bond the two grounding bars together, but as I'm reading more of Grounding and Bonding for the Radio Amateur, it does appear that I should do that for safety's sake and to ensure common voltage.

I'm truly sorry that I lost track of this thread and am only now answering the information that you provided. Since you need to bond the 2 Grounding Electrode Systems to each other anyway you have an opportunity to markedly improve the overall grounding of your home. First Thing: Do NOT run the bonding conductor through the house if you can possibly avoid that. Inviting the energy of a lightning strike to travel through your house to equalize the voltage on the 2 Grounding Electrode Arrays is not a great idea. It sharply raises the likelihood of a side flash from the bonding conductor to the interior wiring and plumbing systems. The energy from a side flash is more than hot enough to kindle a fire.

If you run the inter grounding array conductor outside the home then it can itself become a Grounding Electrode. The name that the US National Electric Code gives for the electrode you can make is a "Ground Ring." A ground ring is 20 or more feet of #2 AWG bare copper conductor, encircling the building, and buried at a depth of 30 inches or more. Your not going to encircle your entire home so your bonding conductor will not be an actual "Ground Ring" but if you look at the first requirement that it be 20 or more feet; think a well or spring house; you will see that doing the half circle that you need to interconnect the 2 separate Grounding Electrode Arrays does offer the same actual ground contact as a ring around a smaller building would. The difference between your half ring and an inter array bonding conductor is that a Ground ring is 3 common wire sizes larger and is buried at least 2 foot deeper than a bonding conductor would be. That does raise the material cost and the amount of labor. Do yourself a favor and rent a trenching machine to dig the trench. They are not terribly expensive to rent and make the job much easier. Check what the cost of #2 bare copper is in your area and compare that to the cost of copper strap conductor between 2 and 6 inches wide. The widest one you can afford is the best choice. Because the voltage rise of a lightning discharge is so very fast it has the same impedance characteristics as a high frequency AC current. For the same cross sectional area the strap conductor will have a much lower impedance because much more of the conductor's cross sectional area will carry the current. The strap conductor gets connected to a rod electrode in each array by sandwiching it between 2 copper plates formed to fit closely around the rod to maximize the contact area between the Strap conductor and the driven rod electrode. Those plates can be purchased ready made but with a little patience you can make your own. Stainless Steel hardware is used to hold the 2 plates on either side of the copper strapping. Emery cloth or fine metal "Sand Paper" is used to remove any surface corrosion from the contact surfaces at the attachment or splicing points. A copper contact sealing paste such as KOPR-SHIELD is used to coat the contact surfaces to exclude water, prevent oxidation, and improve conductivity. Georgia Copper is one source for the strap conductor. It can sometimes be purchased more cheaply at a roofing supply house because the roofing industry uses a lot more copper sheeting strips as flashing for slate roofs than the radio equipment market would ever need.

If you have any questions please ask.

--

Tom W3TDH

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ELMER
On 8/26/2021 at 2:52 PM, W3ESX said:

As for the steel enclosure, no I had no particular reason for picking that other than that I saw a YouTube video with someone building a fully self-contained box with the lightning arresters and an internal ground bar and I quite liked the convenience and compactness of that design. This is the video. Are there any reasons NOT to use the steel enclosure that I am not considering? I will be the first to admit my electrical knowledge is lacking, but I am working to improve it.

 

First what are we trying to do in the entirety of the work. We want the coaxial cable to pass through a lightning arrester and then into the building to your radio operating position. The cable entry point is into the entry box through a bulkhead connector or through the arrestor itself. What that says to me is that the cable comes into the weather proof entry box by it's connection to arrestor or bulkhead threads. The arrestors themselves or the bulkhead connectors used to pass the cable through the wall of the box are all mounted through the bottom wall of the box. That markedly lessens the possibility of water intrusion through the penetrations.  Notice: The smallest knockout opening in an electrical box is a nominal 1/2 inch and an actual 7/8ths inch. It is generally impractical to reduce those down to an actual 1/2 inch that will just fit the male threads on the outside or a female coaxial cable connection. From the inward cable end of the lightning arrestor, in the interior of the entry box, another piece of coaxial cable passes through the back wall of the box into a non metallic conduit nipple which ends at the inside of the wall. Through the same conduit nipple the operating position's Grounding Electrode Conductor will also pass into the entry box and continue down to the Grounding Electrode Array. It must be bonded to the metal of the entry box on it's way through. If you use grounding braid you will terminate that to the interior of the box and ground that bonding point and the box itself to the Grounding Electrode System. The Grounding conductors will be copper in the form of braid or strap. The braid will only be used indoors from the inside of the box to the single point grounding busbar at the operating position. From the outside of the box to the Grounding Electrode array near the antenna lead in entry box use copper strap conductor 4 inches wide.

There are things that you need to be aware of when you use a ferrous metal enclosure such as the steel box shown in that video. The most important factor is that when a conductor passes through a ferrous metal to which it is not bonded the magnetic field created by the current flow will induce a current into the ferrous metal which will then create a magnetic field of it's own. That second magnetic field opposes the first one and creates counter EMF in the form of the opposing magnetic field. That is how you put impedance into an electric circuit. A coil of wire of a given size will have a characteristic impedance. If you place an iron core inside the magnetic field that will raise the impedance of the coil. To eliminate that effect, and all of the unwanted secondary effects that it might cause, install the lightning arrester through the wall of the steel box through a hole that is only large enough to let the threads go through. After removing any coatings such as paint and any surface corrosion, which is not visible until it has progressed into the metal beneath the surface, you apply anti oxidant paste for steel and put a stainless steel fender washer between the arrester and steel, and between the steel and the arrestor locking nut. You end up with one fender washer on each side of the steel with the threaded portion of the connector on one end of the arrestor passing through the fender washers and held in place by the thread nut on the other side.  The fender washers provide a greater contact area between the arrestor body and the mild steel of the box while isolating the dissimilar metals from direct contact. Again you will use an anti corrosion paste which is suitable for the metals you are using between the fender washers and the steel wall of the box.

Should you want to duck much of that work then use an Aluminum box. Since the box and the arrester block are both aluminum all of the dissimilar metal issues go away. Since the Aluminum of the box is not magnetic it is unlikely to add unwanted impedance to the Grounding Electrode Conductor path. To duck the cost of an aluminum box you can buy a plastic box instead. You will need to install a copper grounding busbar in the back of the box and you will need to connect it to the Grounding Electrode Array with a low impedance conductor. The aluminum box may be the most expensive but it is the least work.

To make the penetrations water tight use sealing nuts or washers on the outside of the box and o-rings on the inside of the box. Do not use washers on both the inside and outside of the box as that will break the bonding connection between the box and the arrestor. By using bulkhead barrel connectors anywhere the coaxial cable enters the enclosure you overcome the connector's size not being able to pass through the hole that is only as large as the outside of the bulkhead connector or arrestor threads. 

If you are determined to pass unbroken coaxial jacket through the wall of the box you need a cord connector that has a sealing gland through which the coaxial connector will pass and that will make an air and watertight seal once the gland nut is tightened down. That would provide you with some additional choices which in my not humble opinion you do not need. If you place the cord connector gland nut and seal over the coaxial cable prior to attaching the connector you will increase the work you do and have reduced options in changing the cable routing later.

--

Tom W3TDH

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ELMER
On 8/24/2021 at 9:27 AM, W3ESX said:

Here is my initial diagram of the grounding system, mounted low to the ground as @K3MRI recommended. The diagram leaves a little to be desired, but it's a rough sketch so I'm OK with that.

The primary problem I'm struggling with at the moment is how to get a grounding strap from the pass-through panel in the window down to the GND unit in the least-obvious way possible. I a) don't want it to drape over the window (the shutters are screwed to the house, so can't go behind them, sadly) and b) am worried about all the 90º turns that would have to be made to route it around all the windows and other items.

Any advice is welcome. I have started purchasing some of the parts for this that I know I will need, including a 40" mast that I am very excited to put up.

73 de W3ESX

I don't know how I missed the station being on the second floor even though mine is as well. I had the coaxial cable entering up high on the house for years but I'm finally biting the bullet and running the coaxial cable up through the interior of my home inside rigid and flexible metallic (steel) conduit. The conduit will provide some shielding to the coaxial cable from magnetic fields generated by Lightning discharge. The only conductors which will run down the outside wall of the house are:

The Grounding Electrode Conductor that will ground the antenna mast itself, and also the operating position's single point bonding busbar to the Grounding Electrode Array at that end of the house were the shack is.

The coaxial cable from the multi band vertical mounted at the peak of one gable end of the house is my biggest challenge. I am ambivalent about how to route that coaxial cable down from the antenna to the shack. I'm very tempted to run the coaxial cable through an arrestor on the mast and inside the house to my shack. What I'm actually going to do is to run it on top of the copper strap Grounding Electrode Conductor which will run down the outside wall of the house from the antenna mast. I'll still have an arrestor on the antenna mast and I may bond the shield of the coaxial cable to the nearest Grounding Electrode at the bottom of that coaxial run just a few feet off the ground. That is were the coaxial cable will loop back up into the cable entry box. The Grounding Electrode Conductor will continue to the nearest electrode of the Grounding Electrode Array at that end of the house. The cable entry box will be at the front corner of that end of the house so that the cables will enter into the basement just below the first floor closet in which the cable raceway conduit will run on the inside of the house back up to the shack on the second floor.

That is the way that we did it on towers when I was still working. 1 arrestor at the top of the tower, coaxial cable shield bonded to the tower every so many feet, arrestor at the base of the tower to take advantage of the grounding electrode system at the base of the tower, into a conduit box at the top of the non metallic conduit run to the communications shelter, out of the conduit run and up the outside of the shelter to the cable entry bulkhead, through which the shelter lightning arrestor was mounted, and then on to the equipment in the shelter.

The biggest challenge may well be getting a hold of one 10 foot stick of 2" rigid steel conduit. I think that the steel conduit will do a better job of attenuating the magnetic field from a lightning discharge so that it will not induce as much current into the coaxial cable shield. At all of the coaxial connectors which are on the radio equipment at the operating position I'm going to install Polyphaser EMP protectors right on the equipment antenna ports. I' hoping that will help reduce the effects of having the shack on the second floor. Aluminum conduit I can get and I'm going to use a stick of that as the new mast for the tri-band vertical which now sits right at the ridge line. I'm hoping that 5 or 6 feet above the ridge will improve it's performance and maybe even keep it from setting off my smoke detectors.

If my Son, Daughter in law, and Grand Child were not living here with us my shack would move to the basement. That was the plan before his job died in the pandemic.

Jamison W3ESX I don't suppose that you have a practical way of getting your coaxial cables up to your shack through the houses interior?

--

Tom W3TDH

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Tom W3TDH,

First, thank you for the absolute TREASURE TROVE of information here. I have printed it all out and skimmed over it several times (skimmed because I have a 19-month-old and rarely have time to deep-dive on amateur stuff these days...just 5-10 minutes here and there hihi). Once I have fully read and comprehend everything you have written and so thoughtfully put together, I will make a plan for moving forward.

A couple things have changed since the last time I posted on this thread:

  1. I have learned that lightning arresters, in their amateur form, are NOT intended for dispersion of direct lightning strikes, but rather for eliminating the static discharge that may build up from an antenna swaying in the wind and potentially traveling down the feed line to damage sensitive equipment at one end.
  2. As a result of learning this, I called a professional lightning protection system installation company and got a quote for my property...nearly $3k to "do the job proper". So that's a dead end, I just don't have that kind of cash. It was around THIS time that I noticed that there is a lightning rod atop the power pole across the street from my house. I believe the height from ground of this pole is higher than my antenna would be. I am curious if this would be sufficient to protect my property from lightning strikes. (I will still disconnect all equipment during lightning storms for added safety)

If I'm going to have to dig a big ol' trench halfway around the home, trencher tool or no, that may be a big problem, as I just don't have the time to do that kind of thing (or license to do such drastic things from the XYL). It may just be easier to use the existing grounding rod on the opposite side of the house and do long cable runs to the shack side, although in the case of coax this will almost certainly result in some loss unless I upgrade to super fancy LMR400 or some such.

Tom @W3TDH in regards to getting cable through the house...it's possible. I plan on purchasing an MFJ passthru panel and installing it in a window, then passing cables through that. I could potentially move the antenna to the opposite side of the house (non-shack-side/grounding-rod-side), run the coax down the side of the house, through the passthru panel, over the joist in the basement, and up the central column which I believe connects to the attic, and then into my shack. And then I could run the equipment grounding wire from the grounding bus in the shack along the same route, back out through the passthru panel, and over to the grounding rod. However, I believe as discussed previously we decided it's not the best idea to run a grounding wire parallel to a signal line.

Back to the drawing board!

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  • 5 weeks later...

grounding?

what, how and why?

in the area i live in one can not just pound in a rod as there is lots of solid rock. not slab.  heck even pg&e could not drill to lay in a new gas pipe, they kept breaking the bits, even the big wheel thingy lost some teeth in just 50 yards of trench. ( the maps of the org piping has been lost, they had to hunt for the old stuff --water, sewer, gas, everything else--).

next door they had to almost diamante the rock to dig out his back yard.

my house is grounded to the gas pipe, wrong side of the house for my tower.  if need be can i just pound in four or five short rods to make it good? as i doubt i can get anything more than 3 - 4 feet down. plenty of dirt, just these hills are made of Hard rock (see the Ca 49er gold rush). maybe the rebar in a short but 15 ft long retaining wall?

not interested in bringing in a drilling rig to make a couple holes in the rock, it would co$t way to much $$$$$. and then the county would put up a stink for $$ for permits. and might even raise my property taxes.

this area is not prone to much lighting, but the thunderheads do make a lot of noise as they go over the sierra mt's. rarely over my head (foothills here).

this area can get a couple storms with lighting a year. (up to 100 miles of my home).

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  • Elmers
ELMER

First things first. Electrical services are never grounded to a gas line because a lightning discharge flowing on gas piping is nearly certain to start a gas fed structure fire! Since you are in California you may have a trembler or excess flow stop valve on your gas line outside the building; or if your gas meter is inside it could be next to the meter. A trembler valve closes when it is shaken by the movement of the earth which accompanies an earthquake. Building codes refer to them as seismic shut-off valves. Excess Flow Valves close when there is a sudden increase of flow such as from a broken pipe or defective appliance. If you do not presently have either a trembler nor excess flow valve you should strongly consider having one installed. I would have both installed since a trembler valve will not respond to excess flow without ground movement. Why yes I do volunteer with the Department of Redundancy Department. Thank you for asking.

 

Interior portions of fuel gas lines are required to be bonded to the electrical system ground but the National Electric Code (NEC) recognizes the Equipment Grounding Conductor (Green Wire) in the wiring to a gas appliance as serving that purpose. A separate bond wire is not required nor desirable. There are 2 Unions in your gas line on either side of your gas meter to permit it's removal for replacement or servicing. The one on the supply, street, side of the gas meter should be replaced with a Dielectric; that means electrically insulating; union. They can be exchanged 1 for 1 as long as the pipe thread sizes are the same as the existing conductive pipe union. The gas fitter can install the dielectric union at the same time he/she installs your new valve/s. Unless you have worked in the plumbing, air conditioning, or pipe fitting crafts installing the replacement dielectric union is NOT a do it yourself project. Fuel gas is nothing to fool around with. I am retired out of 45 years of service as a volunteer firefighter and emergency medical technician. I responded to 3 gas explosions during my service and in 2 of them the house was entirely destroyed. The reason for installing a dielectric union is to avoid lightning current equalizing across the surface of the earth via your interior gas piping.

 

Now back to your grounding electrode system construction. It is important to note that driven rods are only one of several Grounding Electrodes recognized by the National Electric Code (NEC). Another electrode is a 2 foot square copper plate which is 0.06 inches thick. Plate electrodes shall be installed not less than 750 mm (30 in.) below the surface of the earth. Ground rods can be laid flat in a trench in soil were they cannot be driven. "where rock bottom is encountered at an angle up to 45 degrees, the electrode shall be permitted to be buried in a trench that is at least 750 mm (30 in.) deep." It is still required that 8 feet of rod be in contact with the soil. Most Amateur Radio Operators in locations as rocky as yours do not end up using driven rods for grounding. That is because their operating location is seldom immediately adjacent to the location of their electric Service Disconnecting Means. The reason that is important is that the Grounding Electrode System (GES) of the Electrical Service must be bonded to the GES of the Radio antenna and the antenna lead in lightning protector. So before I can advise you any further I would need to know how far apart those 2 locations are from each other.

 

 

--

 

Tom Horne W3TDH

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power main to pole is about 20 feet. all concrete walk areas. power is on the south wall,(narrow patch of dirt there). the location for the pole is on the west. there is one door, (used as main access to the house) and one window between them. can run under the house.  the cable co grounded to a water spigot. just out of the wall into the house.

but there is a wire tied into the gas pipe, it is were the piping comes out of the wall. the line coming up from the ground has a wire coming out of the "cover" pvc but connects to nothing. (new gas piping up from the street just about 3-4 years back). there is only the big meter box and the flat dish thingy. no auto shut off device seen.

earthquakes just do not happen here. might one day but not the norm. but seeing as the power company not a sub contractor put in the new gas piping in the street up to my house (and others for a couple miles around here). i hope they at least did what the county says must be done.

when i can afford a proper tower, it will be a bit farther away from the house. this pole will be bolted to the concrete, attached to a eve of the house (6 ft level), and guy wires up about 28 ft.

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ELMER
9 hours ago, W3TDH said:

Now back to your grounding electrode system construction. It is important to note that driven rods are only one of several Grounding Electrodes recognized by the National Electric Code (NEC). Another electrode is a 2 foot square copper plate which is 0.06 inches thick. Plate electrodes shall be installed not less than 750 mm (30 in.) below the surface of the earth. Ground rods can be laid flat in a trench in soil were they cannot be driven. "where rock bottom is encountered at an angle up to 45 degrees, the electrode shall be permitted to be buried in a trench that is at least 750 mm (30 in.) deep." It is still required that 8 feet of rod be in contact with the soil. Most Amateur Radio Operators in locations as rocky as yours do not end up using driven rods for grounding. That is because their operating location is seldom immediately adjacent to the location of their electric Service Disconnecting Means. The reason that is important is that the Grounding Electrode System (GES) of the Electrical Service must be bonded to the GES of the Radio antenna and the antenna lead in lightning protector. So before I can advise you any further I would need to know how far apart those 2 locations are from each other.

Tom, we had the exact same scenario growing up in the Québec Laurentians, the oldest rock on Earth, igneous of course! My dad had laid out flat copper plates all over the land. Some of those plates, actually most of them, are still there to this day. Not sure if he met the NEC standards, but knowing him, he probably exceeded them 🤨

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  • Elmers
ELMER
13 hours ago, KG6TGU said:

 

 

13 hours ago, KG6TGU said:

power main to pole is about 20 feet. all concrete walk areas. power is on the south wall,(narrow patch of dirt there). the location for the pole is on the west. there is one door, (used as main access to the house) and one window between them. can run under the house.  the cable co grounded to a water spigot. just out of the wall into the house.

but there is a wire tied into the gas pipe, it is were the piping comes out of the wall. the line coming up from the ground has a wire coming out of the "cover" pvc but connects to nothing. (new gas piping up from the street just about 3-4 years back). there is only the big meter box and the flat dish thingy. no auto shut off device seen.

earthquakes just do not happen here. might one day but not the norm. but seeing as the power company not a sub contractor put in the new gas piping in the street up to my house (and others for a couple miles around here). i hope they at least did what the county says must be done.

when i can afford a proper tower, it will be a bit farther away from the house. this pole will be bolted to the concrete, attached to a eve of the house (6 ft level), and guy wires up about 28 ft.

Just so I get this clear the 20 feet you mentioned is the distance between your Electrical Service and the Electric Utility's Power Pole on the west? Cable companies always take the cheapest way out even when the results are dangerous. Is your interior water piping metallic?

Is the new gas piping plastic? The flat dish thingy is the pressure relief valve that protects your home from a failure of the regulator that reduces the pressure from the transmission level down to the distribution level. That regulator may also reduce the pressure again because the pressure inside most homes is equivalent to that of a few inches of standing water. That is why the regulator is vented to the open air. If your home's gas fueled appliances were subjected to distribution pressure far too much gas would flow and a gas fueled structure fire is the likeliest outcome. The County does not get a say over the distribution of fuel gas. That is under control of whatever your state calls their utility regulatory agency.  Since you do not have an earthquake threat in your area you do not need a Trembler Valve. It would still be a very good idea to have an excess flow valve installed. Excess flow valves will only permit the gas required by your gas appliances ti flow through it. It is adjusted to that flow at the time of installation. Any flow above that which the appliances would consume causes the valve to shut off the flow. You have used the word pole in 2 different places. To test for transfer I ask if the first one is a Utility Pole which carries electrical distribution wires and communications through you neighborhood. Just to keep things a little  clearer I will refer to your antenna support "pole" as a Mast. Please explain what you mean by "attached to a eve of the house (6 ft level)?" The Eaves of a house are just below the roof line so an eave at a 6 foot level is not clear to me. The usual place to attach the house bracket of an antenna mast is to a reinforced pair of studs in the gable end of the attic or to a reinforcing piece immediately behind the Rake Board. Alternatively it can be attached to the top plate of the wall of the uppermost floor right underneath the drip edge at the horizontal edge of the roof. The gable end just beneath the ridge line is the preferred point of attachment because it is higher on the mast and provides more resistance to wind. It is rather rare to guy a house bracketed mast or tower unless it extends 10 or more feet above the point of attachment. As an aside there are rigid bars available in various lengths that are routinely used to stabilize Electrical Service Masts to which a service drop from the utility pole is attached above the roof when the direction of pull caused by the pull of the service drop cannot be countered by guy wires. They can also be used to stabilize an antenna mast without needing to run guy wires down off of the roof.

Now back to your actual Grounding Electrode System (GES). To construct the GES for your antenna mast and antenna lead in conductor lightning arrester you have a few options. You could dig 31 inch deep trenches into which to bury the rods, bury 2 X 2 foot plates 30 inches below finished grade, or install a partial ground ring. You would connect the rods or plates to the antenna lead in entry protector and the antenna mast with a Grounding Electrode Conductor (GEC) of #6 American Wire Gauge (AWG) using termination methods which are suitable for use with the metals you are terminating the GEC to.

That leaves you with the real need to bond the 2 GES to each other. You run a minimum #6 AWG copper conductor between the 2 GES to maintain the voltage between them as close to zero as possible. You don't need to worry if both of them rise to 1000s of volts as long as they stay in step and dance to the same tune. By that I mean that there has to be a difference in potential; which is measured in volts; which exceeds the withstand of the insulation in any attached wiring; to make a destructive current flow. Here is were you can save money and effort. The Ground Ring which I mentioned above is 20 or more feet of #2 AWG copper wire encircling the building at a minimum depth of 30 inches below finished grade. You will only be going 1/2 of the way around the hose so technically you will not be installing a Ground Ring electrode. Notice, though, that the minimum length of a ground ring is 20 feet in order to move it out from things like well houses and irrigation control sheds to make it long enough to be reasonable effective. Going part way around the house will be more than 20 feet so it will function better than a "Ground Ring" for a well or spring house would. Neither you nor the electrons care if it meets the code requirement for a "Ground Ring." What matters is that it provides enough soil contact area to allow the current to dissipate across the effected surface of the earth. So just install a #2 AWG GES bonding conductor, rather than the # 6 minimum required, at a depth of 30 inches between the 2 Grounding Systems. The Grounding Electrode for your antenna mast and antenna lead in conductor entry point will be the partial ground ring. when you connect it to the electrical service It will become part of that Grounding Electrode System. You will then use that one common Grounding Electrode System to ground your radio station. A way to make the partial Ground Ring much more effective is to substitute copper strap conductor for the round #2AWG wire that is called out in the National Electric Code. The cross sectional area of #2 copper is 0.0521 square inches. Do the math for the cross sectional area of the copper strap and buy the least expensive copper strap which exceeds the cross sectional area of the #2AWG copper wire. There are several sources of copper strap conductor, such as Georgia Copper and some roofing supply houses; copper is used as the material to flash slate and tile roofs. Georgia Copper is just a vendor that I know the name of off the top of my head. There are several others and it is definitely worth shopping around. Prices vary widely.

Note: The partial ground ring must be terminated to one of the acceptable points of the Electrical Service Equipment. You cannot connect it to a driven rod or buried plate  electrode because the GEC which connects either of those to the Service Equipment is too small to let the partial ground ring be fully effective. Use a long enough #2AWG copper to reach all the way to the service equipment. By definition the Service Equipment is the enclosure which contains the Service Disconnecting Means. That is the first Switch, Fused Pull Out, or Circuit Breaker which will open, meaning disconnect, all of the energized conductors which supply electrical power to the home.

One thing that would help me fully understand your situation would be a picture of your Electrical Meter Base Enclosure, often called the meter pan or can, which is wide enough to include the meter and the ground beneath it along with the point were the conductors from the meter enter the house. With that if front of me I can fully describe were the partial ground ring will be connected to your service equipment.

--

Tom Horne W3TDH

 

Mast guy rods.jpg

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ok,

  to me the "pole" is my mast. not the service pole. that service pole is a good 30-35 feet away angled across the driveway.

 the mast is along the rear of the house. (like were the green ladder is in the photo) as the end of the house is were the high voltage line arrives on the roof. (to something that looks like your photo).

 the end of the house with the power in. ground is concrete, (south wall), and i use the back door for access in and out of the house.

the wall with my mast (west wall), ground all concrete out to 5 feet,

north wall, ground is concrete house to fence about 4 feet.

east wall (front of the house) porch mid way is a concrete block/slab, and "standard" 3 ft wide walkway with flower bed to the wall of the house to the driveway, (south east of the house).

as to the "eve" as the mast is along the wall were the rain gutter is. i built up a bracket to drop below the rain gutter to attach to the mast. as i do not want to drill through the roof.

as to the fresh water piping in the house. yes made of metal. house built in 1952. so the water out, is a clay pipe.

wiring is two wire, cloth covered. i get a lot of static shocks, heck even when i touch my pu truck. but the wall switch boxes are metal. (if i could afford it i would rewire the whole house).

new gas piping is metal, just were it comes up out of the dirt there is pvc over it, shovel protection? water protection? it is in the flower bed on the front of the house.

but same end of the house as the power, cable, land line phone all come to the house. (all wires on on the south end of the house. anchored within a couple yards of each other). power up on the "stick" others just to the edge of the roof. all on the outside of the wall, including the meter and fuse cabinet. this box has been a up grade some time back as the org went down through the roof and was inside. so i have two of the power sticks up there, one in use one to hold the support cable.

 

i will try to get some photos posted up here, but has to wait till next week. as friday is my monday. will only see the house while the sun is down till tuesday. heck i am supposed to be in bed but woke up , i am trying to get used to a new work bid, it is a 12 hr off set to what i have been doing for the past 3-4 years. ( i am a day walker now).

 

                                     W

                      -----3-----------------------

                      |                                              |

           S         |                                              |

                -2-                                                |      N

            1 |                                                      |

              --------4-----------5-------------

                                E

 

basic shape of the house.  1,power/cable/land line phone to the house. 2, back door, 3 my mast. 4 gas meter. 5 front door (blocked)

lots of windows around the house, ridge line of the roof runs s to n.

Edited by KG6TGU
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  • Elmers
ELMER
10 hours ago, KG6TGU said:

ok,

  to me the "pole" is my mast. not the service pole. that service pole is a good 30-35 feet away angled across the driveway.

 the mast is along the rear of the house. (like were the green ladder is in the photo) as the end of the house is were the high voltage line arrives on the roof. (to something that looks like your photo).

 the end of the house with the power in. ground is concrete, (south wall), and i use the back door for access in and out of the house.

the wall with my mast (west wall), ground all concrete out to 5 feet,

north wall, ground is concrete house to fence about 4 feet.

east wall (front of the house) porch mid way is a concrete block/slab, and "standard" 3 ft wide walkway with flower bed to the wall of the house to the driveway, (south east of the house).

as to the "eve" as the mast is along the wall were the rain gutter is. i built up a bracket to drop below the rain gutter to attach to the mast. as i do not want to drill through the roof.

as to the fresh water piping in the house. yes made of metal. house built in 1952. so the water out, is a clay pipe.

wiring is two wire, cloth covered. i get a lot of static shocks, heck even when i touch my pickup truck. but the wall switch boxes are metal. (if i could afford it i would rewire the whole house).

new gas piping is metal, just were it comes up out of the dirt there is PVC over it, shovel protection? water protection? it is in the flower bed on the front of the house.

but same end of the house as the power, cable, land line phone all come to the house. (all wires on on the south end of the house. anchored within a couple yards of each other). power up on the "stick" others just to the edge of the roof. all on the outside of the wall, including the meter and fuse cabinet. this box has been a up grade some time back as the org went down through the roof and was inside. so i have two of the power sticks up there, one in use one to hold the support cable.

 

i will try to get some photos posted up here, but has to wait till next week. as Friday is my Monday. will only see the house while the sun is down till Tuesday. heck i am supposed to be in bed but woke up , i am trying to get used to a new work bid, it is a 12 hr off set to what i have been doing for the past 3-4 years. ( i am a day walker now).

 

                                     W

                      -----3-----------------------

                      |                                              |

           S         |                                              |

                -2-                                                |      N

            1 |                                                      |

              --------4-----------5-------------

                                E

 

basic shape of the house.  1,power/cable/land line phone to the house. 2, back door, 3 my mast. 4 gas meter. 5 front door (blocked)

lots of windows around the house, ridge line of the roof runs s to n.

Were does your antenna lead in; such as coaxial cable, twin lead, window line, or ladder line; from the antenna enter the house. Do you have any route between the electrical service equipment at point 1 to the mast at point 3 that is not covered in concrete? When you say that your electrical service mast looks like the one in my picture does that include having 2 guy bars to resist bending forces from the weight of the Service Drop wires from the utility pole? I take it that your present electrical service mast is at point 1. Is the other service mast in the same place or close by? Is the utility pole to the South East? Is the street on the East side of the house?

If you are willing you could give me an address or latitude & longitude so that I could look at the layout on Google Maps Satellite view. If you don't want to make that public you could send it to me in a private message or by E mail to hQoRrMnetd via gmail after you tune out the QRM from the prefix. You can send images direct to me if that helps. The remainder of the conversation should stay here on the reflector for peer review so others can point out any mistakes I might make.

Edited by W3TDH
Improve clarity and remove excess verbiage.
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13 hours ago, W3TDH said:

Were does your antenna lead in; such as coaxial cable, twin lead, window line, or ladder line; from the antenna enter the house.

as of today nothing connected yet. but was going to get some "plastic" and build a pass through at a window next to the mast.

Do you have any route between the electrical service equipment at point 1 to the mast at point 3 that is not covered in concrete?     no.   but can go under the house for such.

When you say that your electrical service mast looks like the one in my picture does that include having 2 guy bars to resist bending forces from the weight of the Service Drop wires from the utility pole? I take it that your present electrical service mast is at point 1. Is the other service mast in the same place or close by? Is the utility pole to the South East? Is the street on the East side of the house?  yes, yes, and yes.

If you are willing you could give me an address or latitude & longitude so that I could look at the layout on Google Maps Satellite view. If you don't want to make that public you could send it to me in a private message or by E mail to hQoRrMnetd via gmail after you tune out the QRM from the prefix. You can send images direct to me if that helps. The remainder of the conversation should stay here on the reflector for peer review so others can point out any mistakes I might make.

i just got home, been up for 24 hrs now. back to work by 6:am sat. dark in ca already so i can do photos on tuesday or wed. (my weekend).

but for now my mast is laying down, need to buy the guy wire and turn buckles.

but the plan is to build a pass through, one window is next to were the mast is to be. easy to lock down and have it secure from unwanted entry. heck it will be far more secure than the glass ever could be.

the power in poles are both the same but one has the extra supports, who ever did the job (predates my owning the place) kept the "factory" pole, as it is in the wall of the house. it takes the weight/strain of the incoming wire. the "down" pipe the power goes into is on the outside of the house.just a couple feet from each other. the pipe just pops through the roof, and drops down the outside wall to the meter box.

this small ex to the house is the laundry room. roof sits a bit lower there. house is on a slight hill. back wall one can touch the rain gutter, not so in front you need a tall ladder.

easy to climb into the windows on the south and west walls. north and east wall you need a step stool to just look into them.

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