Lightning in New Mexico

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Lightning in New Mexico

Phillip Lontz
The ground rod (#1) I placed just outside my shack/ house is about 16 or 17 feet from the meter/ ground rod that connects to the AC mains.  
So if I run a bunch of fat parallel wires that are bonded to BOTH ground rods that will be a good thing to do. (and required...by law)(knock on the the door ITS the ground police)


As a matter of fact during the lightning season I disconnect the antennas from my gear when it looks like the Wx is gonna go south. (South,??? why not North???)

Antennas consist of a 20 meter Gap vertical and nested marconi for 40m and 80m at 24 feet... Kinda like a dipole.
These antennas run to an outside remote coax switch.
I have beat into the dirt another 8' foot ground rod(G.R. #2) next to the outside coax switch
and have installed a Poly Phasor on the output coax that goes into the shack and poly phasors on each of the coax cables from the antennas.
All the poly phasor's ground lugs are connected to ground rod #2. (Each Poly phasor has its own wire going to ground rod #2)

This remote coax switch and ground rod #2 are about 12 feet from the AC mains.

If I understand correctly, I should also bond this ground rod #2 to the the AC mains ground rod as well????

But if I do that then those antennas will be connected to the grounds in the house via the AC mains ground rod?????
This seems counterintuitive? I mean... now there will be the very real possibility of lightning in the house wiring???

Again Thank you for your help!!!


Phil
Santa Fe

P.S... We get lightning almost as bad as Florida.
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Re: Lightning in New Mexico

Jim Brown-10
On 3/28/2011 10:12 PM, Phil Townsend wrote:
> (knock on the the door ITS the ground police)

Grounding regulations are there because they are the right way to
protect people and property from Lightning and from faults on the power
system. They are written in the form of Electrical Building Codes (the
NEC in North America) by some VERY sharp Electrical Engineers who really
do understand radio, audio, video, lightning, and all the other
ramifications of proper grounding. They are not "big government" to be
scorned, they are based on God's Laws of Physics to be learned and
respected.

Our concern is not the "ground police"  (the local Electrical Inspector)
--  it's LIGHTNING or a serious fault on the power line that can make
you a very unhappy guy if you do it wrong.

73, Jim Brown K9YC
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Re: Lightning in New Mexico

gm3sek

> They are not "big government" to be scorned, they are based on God's
>Laws of Physics to be learned and respected.

Amen!


--

73 from Ian GM3SEK
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Re: Lightning in New Mexico

Phillip Lontz
Physics is the lightning police! And I for one do not want them knocking at my door.

Sent from my iPad

On Mar 29, 2011, at 1:41 AM, Ian White GM3SEK <[hidden email]> wrote:

>
>> They are not "big government" to be scorned, they are based on God's
>> Laws of Physics to be learned and respected.
>
> Amen!
>
>
> --
>
> 73 from Ian GM3SEK
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Re: Lightning in New Mexico

Rick Dettinger-3
In reply to this post by Jim Brown-10
The "ground police" would be the local electrical inspector for new  
construction.  If the antenna system is constructed after occupancy,  
the "ground police" would consist of the local fire dept.  
investigation team after the fire.  Any penalty will come from the  
insurance company, not the Sheriff!

73,
Rick Dettinger   K7MW



On Mar 28, 2011, at 10:46 PM, Jim Brown wrote:

> Our concern is not the "ground police"  (the local Electrical  
> Inspector)
> --  it's LIGHTNING or a serious fault on the power line that can make
> you a very unhappy guy if you do it wrong.
>
> 73, Jim Brown K9YC

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Re: Lightning in New Mexico

Don Wilhelm-4
In reply to this post by Phillip Lontz
  Phil,

Despite disconnecting your antennas, you still have to consider that the
coax shields enter the house.

Yes, ground rod #2 (and #3 and all others) are to be bonded to the AC
Electrical Entry ground rod.

I am not sure why that is counterintuitive to you.  Yes, there is a very
real possibility that a lightning surge will be induced in the house
wiring with or without the connection between the grounds.  But if there
is a lightning surge on either the antennas or the house wiring, you
want to keep both at the same potential.

Keeping everything at the same potential during a lightning surge event
is what the bonding is all about.

A lightning surge traveling through the earth can create a very large
difference in potential between ground rods that are not connected
together, and that potential difference can cause fires and damage.  The
soil has more resistance than a wire between the ground rods.

Look at the 2010 (or 2011) ARRL Handbook chapter on Safety - the fact
that ALL ground rods should be connected together is clearly stated.

One other point on disconnecting your antennas - consider what happens
when you re-connect them.  The PL-259 center conductor is connected
first, and then the shell is attached.  If there is a charge on the coax
center conductor, you can zap your equipment by the simple act of
re-connecting it.  Short the center conductor to the grounded shell
before connecting it to your equipment.  It is better to disconnect the
antennas with a switch in the coax line and provide a DC path to ground
across the common coax connector at that switch.

73,
Don W3FPR

On 3/29/2011 1:12 AM, Phil Townsend wrote:

> I have beat into the dirt another 8' foot ground rod(G.R. #2) next to the outside coax switch
> and have installed a Poly Phasor on the output coax that goes into the shack and poly phasors on each of the coax cables from the antennas.
> All the poly phasor's ground lugs are connected to ground rod #2. (Each Poly phasor has its own wire going to ground rod #2)
>
> This remote coax switch and ground rod #2 are about 12 feet from the AC mains.
>
> If I understand correctly, I should also bond this ground rod #2 to the the AC mains ground rod as well????
>
> But if I do that then those antennas will be connected to the grounds in the house via the AC mains ground rod?????
> This seems counterintuitive? I mean... now there will be the very real possibility of lightning in the house wiring???
>
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Re: Lightning in New Mexico

AC7AC
In reply to this post by Phillip Lontz
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Re: Lightning in New Mexico

george fritkin
In reply to this post by Don Wilhelm-4
Let's introduce some facts.  Lightning strikes can carry from 10K to over 50K amps.  That will vaporize #12 wire instantly.  Typical ham installations do not have adequate protection and in fact it is not affordable for the average ham.  When you are in the mist of a storm disconnect everything....I mean unplug and pray that nature spares your antenna.  Storms that are in the proximity may induce high voltage spikes on the power grid so it is hard to evaluate potential damage.
As I said unplug.  Switches, power strips, discharge tubes, are patch solutions.  For safety sake unplug!!
George, W6GF




--- On Tue, 3/29/11, Don Wilhelm <[hidden email]> wrote:

From: Don Wilhelm <[hidden email]>
Subject: Re: [Elecraft] Lightning in New Mexico
To: "Phil Townsend" <[hidden email]>
Cc: "Elecraft Reflector" 
Date: Tuesday, March 29, 2011, 6:23 AM

  Phil,

Despite disconnecting your antennas, you still have to consider that the
coax shields enter the house.

Yes, ground rod #2 (and #3 and all others) are to be bonded to the AC
Electrical Entry ground rod.

I am not sure why that is counterintuitive to you.  Yes, there is a very
real possibility that a lightning surge will be induced in the house
wiring with or without the connection between the grounds.  But if there
is a lightning surge on either the antennas or the house wiring, you
want to keep both at the same potential.

Keeping everything at the same potential during a lightning surge event
is what the bonding is all about.

A lightning surge traveling through the earth can create a very large
difference in potential between ground rods that are not connected
together, and that potential difference can cause fires and damage.  The
soil has more resistance than a wire between the ground rods.

Look at the 2010 (or 2011) ARRL Handbook chapter on Safety - the fact
that ALL ground rods should be connected together is clearly stated.

One other point on disconnecting your antennas - consider what happens
when you re-connect them.  The PL-259 center conductor is connected
first, and then the shell is attached.  If there is a charge on the coax
center conductor, you can zap your equipment by the simple act of
re-connecting it.  Short the center conductor to the grounded shell
before connecting it to your equipment.  It is better to disconnect the
antennas with a switch in the coax line and provide a DC path to ground
across the common coax connector at that switch.

73,
Don W3FPR

On 3/29/2011 1:12 AM, Phil Townsend wrote:

> I have beat into the dirt another 8' foot ground rod(G.R. #2) next to the outside coax switch
> and have installed a Poly Phasor on the output coax that goes into the shack and poly phasors on each of the coax cables from the antennas.
> All the poly phasor's ground lugs are connected to ground rod #2. (Each Poly phasor has its own wire going to ground rod #2)
>
> This remote coax switch and ground rod #2 are about 12 feet from the AC mains.
>
> If I understand correctly, I should also bond this ground rod #2 to the the AC mains ground rod as well????
>
> But if I do that then those antennas will be connected to the grounds in the house via the AC mains ground rod?????
> This seems counterintuitive? I mean... now there will be the very real possibility of lightning in the house wiring???
>
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Re: Lightning in New Mexico

Dave, W8OV
In reply to this post by Don Wilhelm-4
These posts on lightning protection served to get me considering my
shack, etc.  I had solar panels installed last summer, and on the side
of the house opposite the electrical entrance panel the installers ran a
wire from the PV panels, inverters, etc., down to a ground rod they put
in.  So I asked them yesterday if there was any bonding of that rod to
the ground on the entrance panel side of the house.  The response was
"They are not bonded.  That ground rod is not a system ground and does
not need to be bonded to the existing grounding system.  It is purely
for lightning protection."

--Dave, W8OV

On 3/29/2011 8:23 AM, Don Wilhelm wrote:

>    Phil,
>
> Despite disconnecting your antennas, you still have to consider that the
> coax shields enter the house.
>
> Yes, ground rod #2 (and #3 and all others) are to be bonded to the AC
> Electrical Entry ground rod.
>
> I am not sure why that is counterintuitive to you.  Yes, there is a very
> real possibility that a lightning surge will be induced in the house
> wiring with or without the connection between the grounds.  But if there
> is a lightning surge on either the antennas or the house wiring, you
> want to keep both at the same potential.
>
> Keeping everything at the same potential during a lightning surge event
> is what the bonding is all about.
>
> A lightning surge traveling through the earth can create a very large
> difference in potential between ground rods that are not connected
> together, and that potential difference can cause fires and damage.  The
> soil has more resistance than a wire between the ground rods.
>
> Look at the 2010 (or 2011) ARRL Handbook chapter on Safety - the fact
> that ALL ground rods should be connected together is clearly stated.
>
> One other point on disconnecting your antennas - consider what happens
> when you re-connect them.  The PL-259 center conductor is connected
> first, and then the shell is attached.  If there is a charge on the coax
> center conductor, you can zap your equipment by the simple act of
> re-connecting it.  Short the center conductor to the grounded shell
> before connecting it to your equipment.  It is better to disconnect the
> antennas with a switch in the coax line and provide a DC path to ground
> across the common coax connector at that switch.
>
> 73,
> Don W3FPR
>
> On 3/29/2011 1:12 AM, Phil Townsend wrote:
>> I have beat into the dirt another 8' foot ground rod(G.R. #2) next to the outside coax switch
>> and have installed a Poly Phasor on the output coax that goes into the shack and poly phasors on each of the coax cables from the antennas.
>> All the poly phasor's ground lugs are connected to ground rod #2. (Each Poly phasor has its own wire going to ground rod #2)
>>
>> This remote coax switch and ground rod #2 are about 12 feet from the AC mains.
>>
>> If I understand correctly, I should also bond this ground rod #2 to the the AC mains ground rod as well????
>>
>> But if I do that then those antennas will be connected to the grounds in the house via the AC mains ground rod?????
>> This seems counterintuitive? I mean... now there will be the very real possibility of lightning in the house wiring???
>>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
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Re: Lightning in New Mexico

Don Wilhelm-4
  Dave,

I believe you would get the opposite answer from a qualified electrician
or your county inspector.  Maybe one with the proper credentials will
answer on this list.

73,
Don W3FPR

On 3/29/2011 12:20 PM, Dave, W8OV wrote:

> These posts on lightning protection served to get me considering my
> shack, etc.  I had solar panels installed last summer, and on the side
> of the house opposite the electrical entrance panel the installers ran a
> wire from the PV panels, inverters, etc., down to a ground rod they put
> in.  So I asked them yesterday if there was any bonding of that rod to
> the ground on the entrance panel side of the house.  The response was
> "They are not bonded.  That ground rod is not a system ground and does
> not need to be bonded to the existing grounding system.  It is purely
> for lightning protection."
>
> --Dave, W8OV
>
> On 3/29/2011 8:23 AM, Don Wilhelm wrote:
>>     Phil,
>>
>> Despite disconnecting your antennas, you still have to consider that the
>> coax shields enter the house.
>>
>> Yes, ground rod #2 (and #3 and all others) are to be bonded to the AC
>> Electrical Entry ground rod.
>>
>> I am not sure why that is counterintuitive to you.  Yes, there is a very
>> real possibility that a lightning surge will be induced in the house
>> wiring with or without the connection between the grounds.  But if there
>> is a lightning surge on either the antennas or the house wiring, you
>> want to keep both at the same potential.
>>
>> Keeping everything at the same potential during a lightning surge event
>> is what the bonding is all about.
>>
>> A lightning surge traveling through the earth can create a very large
>> difference in potential between ground rods that are not connected
>> together, and that potential difference can cause fires and damage.  The
>> soil has more resistance than a wire between the ground rods.
>>
>> Look at the 2010 (or 2011) ARRL Handbook chapter on Safety - the fact
>> that ALL ground rods should be connected together is clearly stated.
>>
>> One other point on disconnecting your antennas - consider what happens
>> when you re-connect them.  The PL-259 center conductor is connected
>> first, and then the shell is attached.  If there is a charge on the coax
>> center conductor, you can zap your equipment by the simple act of
>> re-connecting it.  Short the center conductor to the grounded shell
>> before connecting it to your equipment.  It is better to disconnect the
>> antennas with a switch in the coax line and provide a DC path to ground
>> across the common coax connector at that switch.
>>
>> 73,
>> Don W3FPR
>>
>> On 3/29/2011 1:12 AM, Phil Townsend wrote:
>>> I have beat into the dirt another 8' foot ground rod(G.R. #2) next to the outside coax switch
>>> and have installed a Poly Phasor on the output coax that goes into the shack and poly phasors on each of the coax cables from the antennas.
>>> All the poly phasor's ground lugs are connected to ground rod #2. (Each Poly phasor has its own wire going to ground rod #2)
>>>
>>> This remote coax switch and ground rod #2 are about 12 feet from the AC mains.
>>>
>>> If I understand correctly, I should also bond this ground rod #2 to the the AC mains ground rod as well????
>>>
>>> But if I do that then those antennas will be connected to the grounds in the house via the AC mains ground rod?????
>>> This seems counterintuitive? I mean... now there will be the very real possibility of lightning in the house wiring???
>>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>>
> ______________________________________________________________
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>
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>
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Re: Lightning in New Mexico

Phillip Lontz
In reply to this post by george fritkin
George said "disconnect everything and pray...."
So, George would you disconnect you antenna from it's ground????




On Mar 29, 2011, at 10:09 AM, george fritkin wrote:

> Let's introduce some facts.  Lightning strikes can carry from 10K to over 50K amps.  That will vaporize #12 wire instantly.  Typical ham installations do not have adequate protection and in fact it is not affordable for the average ham.  When you are in the mist of a storm disconnect everything....I mean unplug and pray that nature spares your antenna.  Storms that are in the proximity may induce high voltage spikes on the power grid so it is hard to evaluate potential damage.
> As I said unplug.  Switches, power strips, discharge tubes, are patch solutions.  For safety sake unplug!!
> George, W6GF
>
>
>
>
> --- On Tue, 3/29/11, Don Wilhelm <[hidden email]> wrote:
>
> From: Don Wilhelm <[hidden email]>
> Subject: Re: [Elecraft] Lightning in New Mexico
> To: "Phil Townsend" <[hidden email]>
> Cc: "Elecraft Reflector"
> Date: Tuesday, March 29, 2011, 6:23 AM
>
>   Phil,
>
> Despite disconnecting your antennas, you still have to consider that the
> coax shields enter the house.
>
> Yes, ground rod #2 (and #3 and all others) are to be bonded to the AC
> Electrical Entry ground rod.
>
> I am not sure why that is counterintuitive to you.  Yes, there is a very
> real possibility that a lightning surge will be induced in the house
> wiring with or without the connection between the grounds.  But if there
> is a lightning surge on either the antennas or the house wiring, you
> want to keep both at the same potential.
>
> Keeping everything at the same potential during a lightning surge event
> is what the bonding is all about.
>
> A lightning surge traveling through the earth can create a very large
> difference in potential between ground rods that are not connected
> together, and that potential difference can cause fires and damage.  The
> soil has more resistance than a wire between the ground rods.
>
> Look at the 2010 (or 2011) ARRL Handbook chapter on Safety - the fact
> that ALL ground rods should be connected together is clearly stated.
>
> One other point on disconnecting your antennas - consider what happens
> when you re-connect them.  The PL-259 center conductor is connected
> first, and then the shell is attached.  If there is a charge on the coax
> center conductor, you can zap your equipment by the simple act of
> re-connecting it.  Short the center conductor to the grounded shell
> before connecting it to your equipment.  It is better to disconnect the
> antennas with a switch in the coax line and provide a DC path to ground
> across the common coax connector at that switch.
>
> 73,
> Don W3FPR
>
> On 3/29/2011 1:12 AM, Phil Townsend wrote:
>> I have beat into the dirt another 8' foot ground rod(G.R. #2) next to the outside coax switch
>> and have installed a Poly Phasor on the output coax that goes into the shack and poly phasors on each of the coax cables from the antennas.
>> All the poly phasor's ground lugs are connected to ground rod #2. (Each Poly phasor has its own wire going to ground rod #2)
>>
>> This remote coax switch and ground rod #2 are about 12 feet from the AC mains.
>>
>> If I understand correctly, I should also bond this ground rod #2 to the the AC mains ground rod as well????
>>
>> But if I do that then those antennas will be connected to the grounds in the house via the AC mains ground rod?????
>> This seems counterintuitive? I mean... now there will be the very real possibility of lightning in the house wiring???
>>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html

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Re: Lightning in New Mexico

Jim Brown-10
In reply to this post by Dave, W8OV
On 3/29/2011 9:20 AM, Dave, W8OV wrote:
> So I asked them yesterday if there was any bonding of that rod to
> the ground on the entrance panel side of the house.  The response was
> "They are not bonded.  That ground rod is not a system ground and does
> not need to be bonded to the existing grounding system.  It is purely
> for lightning protection."

Tell them to study Section 250 of the NEC.  A bond between their rod and
the mains power system ground is absolutely required, both by the NEC
and the LAWS of PHYSICS!

73, Jim K9YC
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Re: Lightning in New Mexico

k6dgw
In reply to this post by Phillip Lontz
On 3/29/2011 5:12 AM, Phil Townsend wrote:
> As a matter of fact during the lightning season I disconnect the antennas from my gear when it looks like the Wx is gonna go south.
A good idea, but the cables still enter your shack.  Potentials that can
create a "spark" a mile long won't be fazed by a gap a few feet long.  :-)
> If I understand correctly, I should also bond this ground rod #2 to the the AC mains ground rod as well????
If there was no connection between your antenna system and equipment in
your home, you wouldn't need to, but of course, there *is* a connection
to your radio equipment inside so, "yes," you should bond the grounds
together.
> But if I do that then those antennas will be connected to the grounds in the house via the AC mains ground rod?????
> This seems counterintuitive? I mean... now there will be the very real possibility of lightning in the house wiring???
Power utilities work on HV lines while they're hot.  They can do this so
long as the worker(s) and all their equipment and apparatus are at the
same potential.  It's a difference in potential that causes current to
flow, and it's the current that creates the safety hazard.  The goal of
the electrical codes is to assure that a fault in the electrical system,
or something outside like lightning, cannot force a difference in
potential between the grounds.  We can't keep lightning from "going"
where it wants to, but we can take steps to assure that everything
conductive ends up at close to the same potential.

None of this discussion really applies to a direct lightning strike.  A
direct strike to your antenna will likely vaporize it, your coax, any
wire you use to bond grounds together,  and probably set fire to
anything flammable in the vicinity.  The lightning problems we can deal
with are currents induced in conductors from the impulse of near-by strikes.

73,

Fred K6DGW
Auburn CA


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Re: Lightning in New Mexico

David Christ
In reply to this post by Jim Brown-10
It is a pity that the NEC is so expensive ($85 list $67 Amazon) and
changes with revisions every three years.  It is a book that should
be on a lot of amateur's bookshelves.  Not always easy reading but is
very carefully written and defines best practices.  Interestingly
enough it is published by the National Fire Protection Association
(NFPA).  Insurance companies are not interested in paying out so they
want things to be done safely.  This is a good example of industry
and government cooperation.  The industry experts figure out what is
best and safest.  The government makes people pay attention.  My son
and I had a lot of fun taking NEC rules and discussing not the rule
but the reason the rule was there.  Guess we were a couple of nerds.
But the rules were not arbitrary.  There was always a safety related
reason.


David K0LUM

At 10:54 AM -0700 3/29/11, Jim Brown wrote:

>On 3/29/2011 9:20 AM, Dave, W8OV wrote:
>>  So I asked them yesterday if there was any bonding of that rod to
>>  the ground on the entrance panel side of the house.  The response was
>>  "They are not bonded.  That ground rod is not a system ground and does
>>  not need to be bonded to the existing grounding system.  It is purely
>>  for lightning protection."
>
>Tell them to study Section 250 of the NEC.  A bond between their rod and
>the mains power system ground is absolutely required, both by the NEC
>and the LAWS of PHYSICS!
>
>73, Jim K9YC
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Re: Lightning in New Mexico [End of topic soon - please limit posts]

Eric Swartz - WA6HHQ
Administrator
In reply to this post by k6dgw
Folks, while this is an interesting topic, we are overloading the list
with the volume of posts regarding it.  Let's wind it down in the next
2-3 hours.

It has also been discussed in detail in many past postings that can be
easily searched for in the Nabble archives.

73,
Eric  WA6HHQ
Elecraft List Moderator
----

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