Tim, et al,
So here's a question about bonding and grounding.
Parts of the described system are done, and others need to get done -
correctly, hence my questions.
10x16 ft ham shack structure with a Rohn 45 thirty feet away from the entrance
panels. Ring ground will loop around both. Ground rods are 8 ft copper clad
steel no more than 7 ft apart. There are nine additional 4 ft ground rods
(three lines of three) spaced 3.5 ft apart extending from each of the three
legs. The ground rods are to be bonded together using bare #6 copper wire and
fastened using acorn nuts. The bare #6 copper wire ring is going to be only
about four inches below tbe soil except at the ground rods. Tbe acorn nuts
will rewuire
The lightning arrestors are in a stainless steel flat cabinet six inches above
the ground with the base plate directly attached to the ring behind the shack
so as to minimize ground resistance at the arrestors. The antenna, network
and control cables leave the arrestor box located on the ground ring and then
are jumpered up onto the antenna/network/control cable entrance bulkhead
connectors on the entrance plate. This entrance plate is six feet away from
the power entrance panel. Both the power entrance panel and the
antenna/network/control entrance plate have their own pience of insulated #6
copper wire connected to the ring ground. There is also a 2x2 inch piece of
aluminum angle connecting the power and antenna/network/control entrance panel
on the inside of the shack wall that also provides the single point ground for
equipment.
A few other notes: There is a Siemens surge protector on the outdoor 200A meter
panel. The 100A shack subpanel is ten feet away. Should I include the 200A
xmain service ground in the ground ring?
Further, is there any benefit to adding a second surge protector on the shack
subpanel? I have one available.
Finally, I have some two inch copper that I bought from DX Engineering in a 25
ft roll. It's a Georgia Copper product. Given your concerns about bare
copper, should this be used only inside the shack?
OK, so have at it...
Vy 73,
Gordon Beattie, W2TTT
201.314.6964
Get On The Air!
________________________________
From: RFI <rfi-bounces+w2ttt=att.net@contesting.com> on behalf of Tim Duffy
<k3lr@k3lr.com>
Sent: Monday, August 16, 2021, 23:08
To: 'K9MA'; 'Eddie Edwards'; rfi@contesting.com
Subject: Re: [RFI] DFing intermittent connection
Remember we are giving advice to all hams on this reflector.
We want to insure we are giving the correct advice
There are no short cuts to doing things the right way
There is only one way to ground and bond - the right way.
73
Tim K3LR
-----Original Message-----
From: RFI [mailto:rfi-bounces+k3lr=k3lr.com@contesting.com] On Behalf Of K9MA
Sent: Monday, August 16, 2021 11:03 PM
To: Eddie Edwards; rfi@contesting.com
Subject: Re: [RFI] DFing intermittent connection
We get plenty of lightning in Wisconsin, but in my case the shunt around
the thrust bearing (and rotator) is mainly to prevent harmonic
generation when shunt feeding the tower. If the tower gets a direct
hit, damaged bearings will be the least of my worries.
73,
Scott K9MA
On 8/16/2021 9:43 PM, Eddie Edwards wrote:
> As long as you don't get a lot of lightning up in Wisconsin, the impedance of
> your entire ground protection system probably doesn't matter as much either.
> But isn't that the point of all the bonding and grounding just in case?
> YMMV
>
> 73, de ed -K0iL
>
> -----Original Message-----
> From: RFI <rfi-bounces+eddieedwards=centurylink.net@contesting.com> On Behalf
> Of K9MA
> Sent: Monday, August 16, 2021 17:42
> To: donovanf@erols.com; rfi@contesting.com
> Subject: Re: [RFI] DFing intermittent connection
>
> Hi Frank,
>
> That makes sense. All I ever used it for was as a shunt around the thrust
> bearing, for which the impedance probably wasn't that critical.
>
> 73,
> Scott K9MA
>
>
> On 8/16/2021 4:44 PM, donovanf@erols.com wrote:
>> Hi Scott,
>>
>> Braid is always a poor choice outdoors unless its under pressure and
>> protected from moisture such as inside jacketed coax cable
>>
>> When its no longer under pressure and protected from moisture the RF
>> resistance of braid goes up dramatically because the crossovers in the
>> braid no longer conduct effectively.
>>
>> That's why the appropriate choice for an outdoor conductor is stranded
>> wire or solid wire and never braid
>>
>> 73
>> Frank
>> W3LPL
>>
>> ----------------------------------------------------------------------
>> --
>> *From: *"K9MA" <k9ma@sdellington.us>
>> *To: *donovanf@erols.com, rfi@contesting.com
>> *Sent: *Monday, August 16, 2021 9:27:16 PM
>> *Subject: *Re: [RFI] DFing intermittent connection
>>
>> Gee, it's worked for me for years. Not much salt spray in Wisconsin.
>>
>> 73,
>> Scott K9MA
>>
>> On 8/16/2021 12:32 PM, donovanf@erols.com wrote:
>>
>> Jim,
>>
>> Please ignore Scott's advice, it will cause tower corrosion and
>> quickly fail
>>
>> 73
>> Frank
>> W3LPL
>>
>> ------------------------------------------------------------------------
>> *From: *"K9MA" <k9ma@sdellington.us>
>> *To: *jimk8mr@aol.com
>> *Cc: *rfi@contesting.com
>> *Sent: *Monday, August 16, 2021 4:30:35 PM
>> *Subject: *Re: [RFI] DFing intermittent connection
>>
>> Or just use the braid from some RG8 and a couple hose clamps.
>>
>>
>>
>> ----------
>>
>> Scott Ellington. K9MA
>>
>> --- via iPhone
>>
>> > On Aug 16, 2021, at 9:27 AM, jimk8mr--- via RFI
>> <rfi@contesting.com> wrote:
>> >
>> > The kit is basically a very heavy, very flexible cable, six
>> feet or so, with lugs on both ends, and clamps with a large flat
>> surface to attach to the mast and to the tower leg. I'd think that
>> the bottom lug could be attached to a tower bolt, or some other
>> low resistance connection to the tower.
>> > It would seem to also be simple to homebrew something a bit less
>> rugged, perhaps using a piece of RG-8, shield and center conductor
>> connected together.
>> >
>> > 73 - Jim K8MR
>> >
>> >
>> >
>> > -----Original Message-----
>> > From: EDWARDS, EDDIE J via RFI <rfi@contesting.com>
>> > To: RFI List <rfi@contesting.com>
>> > Sent: Mon, Aug 16, 2021 9:09 am
>> > Subject: Re: [RFI] DFing intermittent connection
>> >
>> > Just FYi...They told me they only have the bypass kits for
>> standard Rohn towers, but not for the BX or HDBX series towers.
>> Need to make your own for other non-rohn configurations.
>> >
>> > 73, de ed -K0iL
>> >
>> > -----Original Message-----
>> > From: RFI On Behalf Of jimk8mr--- via RFI
>> >
>> >
>> > You might look into DX Engineering's Bearing Bypass Ground Kits
>> DXE-BBGK-2-25-P.
>> > I installed one yesterday for K8AZ. I'm not sure if Tom had a
>> particular problem or it was just as a precaution. It easy to
>> install, the only issue in my case was that the tower had been
>> painted, so some paint scraping was in order. But much easier than
>> replacing a thrust bearing!
>> >
>> > 73 - Jim K8MR
>> >
>> > _______________________________________________
>> > RFI mailing list
>> > RFI@contesting.com
>> > http://lists.contesting.com/mailman/listinfo/rfi
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>> > RFI mailing list
>> > RFI@contesting.com
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>>
>> _______________________________________________
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>>
>> --
>> Scott K9MA
>>
>> k9ma@sdellington.us
>>
> --
> Scott K9MA
>
> k9ma@sdellington.us
>
> _______________________________________________
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>
--
Scott K9MA
k9ma@sdellington.us
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