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Silent power supply for a K3s

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Mark Goldberg

Re: Terminal resistance

I cut a cross-section of my battery cable crimps and it essentially is one
solid block of copper:

See this page:

https://sites.google.com/site/marksrvmods/home/battery-wiring

Note that expensive crimpers are "calibrated". They make one or more
connections on sacrificial wiring and cross-section them to verify that the
crimps are good. Since I cheaped out on a crimper, I did the same to give
me some confidence it was done right. A better crimper with the correct
sized dies would not require the careful multiple crimps I had to do with
this wiring.

I've used the Powerwerx crimping tools on many 15, 30, 45 and 75A
Powerpoles and not had any issues with them. I don't solder them.

73,

Mark
W7MLG
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Bob McGraw - K4TAX

Re: Terminal resistance

In reply to this post by Nate Bargmann

The company for which I previously worked designed and built recording
studio consoles.   In order to eek out every bit of noise, that is
achieve the lowest noise floor, it was necessary to crimp and then
solder the lugs on the power supply cables on both ends. Crimping was
only OK and was done until it was discovered that also soldering the
lugs did lower noise floor a few dB. This leads me to conclude that
crimping AND soldering is preferred, leading to a lower resistance
connection.

For lightning grounding, joints and terminations, soldering alone is not
permitted. Crimping is required.

Yes, lugs can not be soldered alone. They must be crimped first and
THEN soldered.    At the same time, some installations of aeronautical
equipment, along with NASA procedure, I do understand does indicate
sweating solder into the lug and it thereby wicking up into the stranded
wires makes for a "stiff" connection.   This connection is reported to
break under vibration conditions.   I've personally never experienced
such with ham equipment, although I've never carried any into space. I
suppose there is merit to this directive.    Perhaps you FAA and NASA
types can expand this thought.

I am also aware with power distribution systems, a.k.a TVA, it is quite
common to use a crimp method to join wires.   These conductors are
several thousand circular mills in size and are of many layers of
stranded conductors. When properly and completely crimped by a
hydraulic crimp machine, the joint is void of space. If fact, having cut
one of these in half just to see for myself, it appeared as a solid rod
with no voids observed. Thus the strands were compressed to that
degree.    The center strand was steel as the messenger and the five
outer layers of aluminum were alternating in direction of rotation,
clockwise wound and counterclockwise wound.

In most cases, crimping connectors with a crimping tool which has the
correct die for the connector is noted to be satisfactory. On the other
hand, I've seen many cables in various ham applications which were
installed using what ever was handy to mash the sleeve.   That is NOT
crimping. Crimping does not distort the tubular diameter nor round
shape of the sleeve as the correct size die prevents distortion of the
sleeve.   A correct crimping tool puts a dimple in one side of the sleeve.

And now you know the rest of the story.

73

Bob, K4TAX

On 6/16/2019 7:27 PM, Nate Bargmann wrote:

> * On 2019 16 Jun 18:50 -0500, Kidder, George wrote:
>> Interesting data, Don. I wonder if there is any information about
>> resistance variations between soldered and crimped terminals. One might
>> think that, with stranded wire, even a good crimp connection might not
>> solidly involve all of the strands, and might additionally deteriorate
>> with time since oxygen could get between the strands. A good solder job
>> should wet the wire through and (additionally) exclude oxygen. This
>> wouldn't be easy to measure, for sure, but these engineers are cleaver
>> people!
> For what it is worth, the company I worked for prohibited the use of
> soldered connectors for terminating bonding or power wiring. Especially
> with regard to bonding, dissipating any lightning strike energy through
> a soldered connector could cause it to enough to melt the solder. In
> doing some microwave site upgrades I did pull out a previous generation
> of bonding wiring that was soldered and some connectors had signs of
> being heated since installation.
>
> In my shack I use crimp connectors and a quality crimping tool with no
> problems.
>
> 73, Nate, N0NB
>

ke9uw

Re: Terminal resistance

Interesting about the additional soldering and resultant noise reduction. A chart from the Indium Corp shows 63/37 solder to be about 11% of the conductivity of copper. I guess that's better than air though.

https://www.microwaves101.com/encyclopedias/soldering-basics#chart
Microwaves101 | Soldering Basics<https://www.microwaves101.com/encyclopedias/soldering-basics#chart>
Click here to go to our main page on packaging. New for February 2019: here's a link to an update on lead-free solders, from Aerospace Corporation, from 2011.In case you were wondering, the issues with lead-free solders have never really gone away. To put it in perspective, 88% of lead consumed in the United States is used in storage batteries, which are not subject to RoHS.
www.microwaves101.com

Chuck Hawley
[hidden email]

Amateur Radio, KE9UW
aka Jack, BMW Motorcycles

________________________________
From: [hidden email] <[hidden email]> on behalf of Bob McGraw K4TAX <[hidden email]>
Sent: Sunday, June 16, 2019 10:03 PM
To: [hidden email]
Subject: Re: [Elecraft] Terminal resistance

The company for which I previously worked designed and built recording
studio consoles. In order to eek out every bit of noise, that is
achieve the lowest noise floor, it was necessary to crimp and then
solder the lugs on the power supply cables on both ends. Crimping was
only OK and was done until it was discovered that also soldering the
lugs did lower noise floor a few dB. This leads me to conclude that
crimping AND soldering is preferred, leading to a lower resistance
connection.

For lightning grounding, joints and terminations, soldering alone is not
permitted. Crimping is required.

Yes, lugs can not be soldered alone. They must be crimped first and
THEN soldered. At the same time, some installations of aeronautical
equipment, along with NASA procedure, I do understand does indicate
sweating solder into the lug and it thereby wicking up into the stranded
wires makes for a "stiff" connection. This connection is reported to
break under vibration conditions. I've personally never experienced
such with ham equipment, although I've never carried any into space. I
suppose there is merit to this directive. Perhaps you FAA and NASA
types can expand this thought.

I am also aware with power distribution systems, a.k.a TVA, it is quite
common to use a crimp method to join wires. These conductors are
several thousand circular mills in size and are of many layers of
stranded conductors. When properly and completely crimped by a
hydraulic crimp machine, the joint is void of space. If fact, having cut
one of these in half just to see for myself, it appeared as a solid rod
with no voids observed. Thus the strands were compressed to that
degree. The center strand was steel as the messenger and the five
outer layers of aluminum were alternating in direction of rotation,
clockwise wound and counterclockwise wound.

In most cases, crimping connectors with a crimping tool which has the
correct die for the connector is noted to be satisfactory. On the other
hand, I've seen many cables in various ham applications which were
installed using what ever was handy to mash the sleeve. That is NOT
crimping. Crimping does not distort the tubular diameter nor round
shape of the sleeve as the correct size die prevents distortion of the
sleeve. A correct crimping tool puts a dimple in one side of the sleeve.

And now you know the rest of the story.

73

Bob, K4TAX

On 6/16/2019 7:27 PM, Nate Bargmann wrote:

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Chuck, KE9UW

Nr4c

Re: Terminal resistance

This leads me to think if soldering lowered the “noise floor” over just crimping that the crimp wasn’t done properly. A proper crimp doesn’t leave any space for solder to fill

Sent from my iPhone
...nr4c. bill

> On Jun 17, 2019, at 4:32 AM, hawley, charles j jr <[hidden email]> wrote:
>
> Interesting about the additional soldering and resultant noise reduction. A chart from the Indium Corp shows 63/37 solder to be about 11% of the conductivity of copper. I guess that's better than air though.
>
> https://www.microwaves101.com/encyclopedias/soldering-basics#chart
> Microwaves101 | Soldering Basics<https://www.microwaves101.com/encyclopedias/soldering-basics#chart>
> Click here to go to our main page on packaging. New for February 2019: here's a link to an update on lead-free solders, from Aerospace Corporation, from 2011.In case you were wondering, the issues with lead-free solders have never really gone away. To put it in perspective, 88% of lead consumed in the United States is used in storage batteries, which are not subject to RoHS.
> www.microwaves101.com
>
>
>
> Chuck Hawley
> [hidden email]
>
> Amateur Radio, KE9UW
> aka Jack, BMW Motorcycles
>
> ________________________________
> From: [hidden email] <[hidden email]> on behalf of Bob McGraw K4TAX <[hidden email]>
> Sent: Sunday, June 16, 2019 10:03 PM
> To: [hidden email]
> Subject: Re: [Elecraft] Terminal resistance
>
> The company for which I previously worked designed and built recording
> studio consoles. In order to eek out every bit of noise, that is
> achieve the lowest noise floor, it was necessary to crimp and then
> solder the lugs on the power supply cables on both ends. Crimping was
> only OK and was done until it was discovered that also soldering the
> lugs did lower noise floor a few dB. This leads me to conclude that
> crimping AND soldering is preferred, leading to a lower resistance
> connection.
>
> For lightning grounding, joints and terminations, soldering alone is not
> permitted. Crimping is required.
>
> Yes, lugs can not be soldered alone. They must be crimped first and
> THEN soldered. At the same time, some installations of aeronautical
> equipment, along with NASA procedure, I do understand does indicate
> sweating solder into the lug and it thereby wicking up into the stranded
> wires makes for a "stiff" connection. This connection is reported to
> break under vibration conditions. I've personally never experienced
> such with ham equipment, although I've never carried any into space. I
> suppose there is merit to this directive. Perhaps you FAA and NASA
> types can expand this thought.
>
> I am also aware with power distribution systems, a.k.a TVA, it is quite
> common to use a crimp method to join wires. These conductors are
> several thousand circular mills in size and are of many layers of
> stranded conductors. When properly and completely crimped by a
> hydraulic crimp machine, the joint is void of space. If fact, having cut
> one of these in half just to see for myself, it appeared as a solid rod
> with no voids observed. Thus the strands were compressed to that
> degree. The center strand was steel as the messenger and the five
> outer layers of aluminum were alternating in direction of rotation,
> clockwise wound and counterclockwise wound.
>
> In most cases, crimping connectors with a crimping tool which has the
> correct die for the connector is noted to be satisfactory. On the other
> hand, I've seen many cables in various ham applications which were
> installed using what ever was handy to mash the sleeve. That is NOT
> crimping. Crimping does not distort the tubular diameter nor round
> shape of the sleeve as the correct size die prevents distortion of the
> sleeve. A correct crimping tool puts a dimple in one side of the sleeve.
>
> And now you know the rest of the story.
>
> 73
>
> Bob, K4TAX
>
>> On 6/16/2019 7:27 PM, Nate Bargmann wrote:
>> * On 2019 16 Jun 18:50 -0500, Kidder, George wrote:
>>> Interesting data, Don. I wonder if there is any information about
>>> resistance variations between soldered and crimped terminals. One might
>>> think that, with stranded wire, even a good crimp connection might not
>>> solidly involve all of the strands, and might additionally deteriorate
>>> with time since oxygen could get between the strands. A good solder job
>>> should wet the wire through and (additionally) exclude oxygen. This
>>> wouldn't be easy to measure, for sure, but these engineers are cleaver
>>> people!
>> For what it is worth, the company I worked for prohibited the use of
>> soldered connectors for terminating bonding or power wiring. Especially
>> with regard to bonding, dissipating any lightning strike energy through
>> a soldered connector could cause it to enough to melt the solder. In
>> doing some microwave site upgrades I did pull out a previous generation
>> of bonding wiring that was soldered and some connectors had signs of
>> being heated since installation.
>>
>> In my shack I use crimp connectors and a quality crimping tool with no
>> problems.
>>
>> 73, Nate, N0NB
>>
>
> ______________________________________________________________
> 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
> Message delivered to [hidden email]
> ______________________________________________________________
> 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
> Message delivered to [hidden email]

Nate Bargmann

Re: Terminal resistance

In reply to this post by Bob McGraw - K4TAX

* On 2019 16 Jun 22:04 -0500, Bob McGraw K4TAX wrote:
> Yes, lugs can not be soldered alone. They must be crimped first and THEN
> soldered.    At the same time, some installations of aeronautical equipment,
> along with NASA procedure, I do understand does indicate sweating solder
> into the lug and it thereby wicking up into the stranded wires makes for a
> "stiff" connection.   This connection is reported to break under vibration
> conditions.   I've personally never experienced such with ham equipment,
> although I've never carried any into space. I suppose there is merit to
> this directive.    Perhaps you FAA and NASA types can expand this thought.

I've noted this before. Before our shop started using crimp UHF
connectors--RF Industries brand of connectors and crimper--we had a high
failure rate of the kludge that is the PL-259 with the UG-174 adapter
and blobs of solder (some installed by us, most from elsewhere). In
various track machines, trucks, and other railroad equipment I never
replaced a properly installed crimp connector. I did replace a number
that came from the truck outfitters but those would arrive with a short
or without the center pin making contact with the coax center conductor,
but that is another story.

Yes, annealing of the wire when using solder is a no-go where flexing
may occur.

73, Nate, N0NB

--

"The optimist proclaims that we live in the best of all
possible worlds. The pessimist fears this is true."

Web: https://www.n0nb.us GPG key: D55A8819 GitHub: N0NB
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