Awl --

Apropos of the recent thread on wire nutting stranded with solid, are there
any inherent advantages of one over the other? #14-#10.

Stranded is more flexible, an advantage if you have to pull long runs in
bends in EMT, but I find it a pain when connecting outlets, etc.

Stranded can be dicey-er with nicks, missing strands.
But, stranded might give more contact area under screws, in breakers, etc.

At HD, stranded is $5 more on 500 ft coil of 14 and 12: $25 to $30, and $40
to $45.

BX/romex comes which way? Both?

Who uses what and when?
--
EA

On 11/12/2009 7:07 PM Existential Angst spake thus:

Apropos of the recent thread on wire nutting stranded with solid, are there
any inherent advantages of one over the other? #14-#10.

Stranded is more flexible, an advantage if you have to pull long runs in
bends in EMT, but I find it a pain when connecting outlets, etc.

Yes and yes.

Stranded can be dicey-er with nicks, missing strands.

Only missing strands if one cuts them off.

But, stranded might give more contact area under screws, in breakers, etc.

Not an issue.

At HD, stranded is $5 more on 500 ft coil of 14 and 12: $25 to $30, and $40
to $45.

You seem to have pretty well covered all the properties and pros and
cons of solid vs. stranded.

BX/romex comes which way? Both?

Solid only. No need to snake the wires through anything, so no need for
stranded wire here.

Who uses what and when?

You pretty well said it yourself:

o Use stranded wire when pulling through conduit.
o Use solid wire otherwise.


--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?

- harvested from Usenet

On Nov 12, 10:07*pm, "Existential Angst"
wrote:
But, stranded might give more contact area under screws, in breakers, etc..

The contact area of solid wire under the screw will be several times
the cross-sectional area of the wire. Nothing to be gained from more
contact area than that. Stranded also has a tendency to squeeze out
from under the screw and loosen up.

Other than that, I think you covered most of it.

On Thu, 12 Nov 2009 20:04:14 -0800, David Nebenzahl
wrote:

On 11/12/2009 7:07 PM Existential Angst spake thus:

Apropos of the recent thread on wire nutting stranded with solid, are there
any inherent advantages of one over the other? #14-#10.

Stranded is more flexible, an advantage if you have to pull long runs in
bends in EMT, but I find it a pain when connecting outlets, etc.

Yes and yes.

Stranded can be dicey-er with nicks, missing strands.

Only missing strands if one cuts them off.

But, stranded might give more contact area under screws, in breakers, etc.

Not an issue.

At HD, stranded is $5 more on 500 ft coil of 14 and 12: $25 to $30, and $40
to $45.

You seem to have pretty well covered all the properties and pros and
cons of solid vs. stranded.

BX/romex comes which way? Both?

Solid only. No need to snake the wires through anything, so no need for
stranded wire here.

Actually CMPCT-CU conductors in aluminum flex (BX ) cable IS
available. CMPCT-CU is otherwize known as compact copper, or stranded
wire. as per ASTM b-8

Who uses what and when?

The stranded stuff is used where flexability is required - or where
vibration is a problem. You won't find it at the "borg" but I do have
some in my garage.

You pretty well said it yourself:

o Use stranded wire when pulling through conduit.
o Use solid wire otherwise.

On Thu, 12 Nov 2009 20:04:14 -0800, David Nebenzahl
wrote:

On 11/12/2009 7:07 PM Existential Angst spake thus:

Apropos of the recent thread on wire nutting stranded with solid, are there
any inherent advantages of one over the other? #14-#10.

Stranded is more flexible, an advantage if you have to pull long runs in
bends in EMT, but I find it a pain when connecting outlets, etc.

Yes and yes.

Stranded can be dicey-er with nicks, missing strands.

Only missing strands if one cuts them off.

But, stranded might give more contact area under screws, in breakers, etc.

Not an issue.

At HD, stranded is $5 more on 500 ft coil of 14 and 12: $25 to $30, and $40
to $45.

You seem to have pretty well covered all the properties and pros and
cons of solid vs. stranded.

BX/romex comes which way? Both?

Solid only. No need to snake the wires through anything, so no need for
stranded wire here.

Who uses what and when?

You pretty well said it yourself:

o Use stranded wire when pulling through conduit.
o Use solid wire otherwise.


Stranded wire "BX" is available from "Northern Cable" in TC90, MC-THHN
and AC-THH flavours. Google it.

Existential Angst wrote:
Awl --

Apropos of the recent thread on wire nutting stranded with solid, are there
any inherent advantages of one over the other? #14-#10.

Stranded is more flexible, an advantage if you have to pull long runs in
bends in EMT, but I find it a pain when connecting outlets, etc.

Stranded can be dicey-er with nicks, missing strands.
But, stranded might give more contact area under screws, in breakers, etc.

At HD, stranded is $5 more on 500 ft coil of 14 and 12: $25 to $30, and $40
to $45.

BX/romex comes which way? Both?

Who uses what and when?

I don't recall solid conductors in an automobile. Stranded wire is less
subject to metal fatigue from bending or vibration. The smaller a
conductor is, the farther it can flex without bending the metal.

Stuff with 7 or 19 strands is usually classified as Rigid Stranded Wire.

Flexible Stranded Wire usually has 49 strands or more. I'd hate to try
to connect the flexible stuff with a wire nut. Until recently, the NEC
required crimping for it. Now there's an approved screw terminal.

On Nov 12, 10:07�pm, "Existential Angst"
wrote:
Awl --

Apropos of the recent thread on wire nutting stranded with solid, are there
any inherent advantages of one over the other? �#14-#10.

Stranded is more flexible, an advantage if you have to pull long runs in
bends in EMT, but I find it a pain when connecting outlets, etc.

Stranded can be dicey-er with nicks, missing strands.
But, stranded might give more contact area under screws, in breakers, etc..

At HD, stranded is $5 more on 500 ft coil of 14 and 12: �$25 to $30, and $40
to $45.

BX/romex comes which way? �Both?

Who uses what and when?
--
EA

I know most of you are talking for home use, but never use solid where
where are a lot of vibrations such as cars, boats and planes. Solid
will break, whereas stranded won't.

Hank

On Nov 13, 5:44*am, "Hustlin' Hank" wrote:
On Nov 12, 10:07 pm, "Existential Angst"
wrote:



Awl --

Apropos of the recent thread on wire nutting stranded with solid, are there
any inherent advantages of one over the other? #14-#10.

Stranded is more flexible, an advantage if you have to pull long runs in
bends in EMT, but I find it a pain when connecting outlets, etc.

Stranded can be dicey-er with nicks, missing strands.
But, stranded might give more contact area under screws, in breakers, etc.

At HD, stranded is $5 more on 500 ft coil of 14 and 12: $25 to $30, and $40
to $45.

BX/romex comes which way? Both?

Who uses what and when?
--
EA

I know most of you are talking for home use, but never use solid where
where are a lot of vibrations such as cars, boats and planes. Solid
will break, whereas stranded won't.

Hank

No one mentioned the fact that stranded wire, at the same diameter,
can carry more current.
And you could tin the ends of stranded for termination.

bob_v

In article , Bob Villa wrote:

No one mentioned the fact that stranded wire, at the same diameter,
can carry more current.

In residential applications -- nonsense.

First of all, the NEC doesn't make a distinction between solid and stranded in
the limits it places on the ampacity of a conductor. The only factor is size.

Second, presumably you're referring to the "skin effect" -- which at 60Hz is
completely negligible. The frequency needs to be a *lot* higher than that
before there's any noticeable effect.

"Doug Miller" wrote in message
...
In article
, Bob
Villa wrote:

No one mentioned the fact that stranded wire, at the same diameter,
can carry more current.

In residential applications -- nonsense.

First of all, the NEC doesn't make a distinction between solid and
stranded in
the limits it places on the ampacity of a conductor. The only factor is
size.

Second, presumably you're referring to the "skin effect" -- which at 60Hz
is
completely negligible. The frequency needs to be a *lot* higher than that
before there's any noticeable effect.

I was going to bring this up as well.

It depends on how the NEC defines gauge of a wire.

If it accurately sums the cross sectional area of each strand, so that this
sum is equal to the CSA of solid, then the ampacity should be very nearly
equal. But the diameter of the stranded would be slightly bigger -- because
of the inherent inefficient of "packing circles" -- ie, gaps between
non-touching parts of a circle.

If the NEC determines gauge based on diameter, then stranded will have less
ampacity than solid, for the same circle-packing reason -- less net CSA of
copper.

So, how DOES the NEC define "gauge"?
--
EA

Existential Angst wrote:

Awl --

Apropos of the recent thread on wire nutting stranded with solid, are there
any inherent advantages of one over the other? #14-#10.

Stranded is more flexible, an advantage if you have to pull long runs in
bends in EMT, but I find it a pain when connecting outlets, etc.

Stranded can be dicey-er with nicks, missing strands.
But, stranded might give more contact area under screws, in breakers, etc.

At HD, stranded is $5 more on 500 ft coil of 14 and 12: $25 to $30, and $40
to $45.

BX/romex comes which way? Both?

Who uses what and when?
--
EA

Like everyone else said, stranded for flexibility pulling through
conduit and whatnot. For termination at receptacles and the like, get
the back wire type devices, not to be confused with the push wire type
which suck. The back wire have a hole you stick the wire in and then
tighten the screw which clamps the wire solidly. This is similar to
terminals in plugs and works well with stranded wire.

Existential Angst wrote:


It depends on how the NEC defines gauge of a wire.

If it accurately sums the cross sectional area of each strand, so that this
sum is equal to the CSA of solid, then the ampacity should be very nearly
equal. But the diameter of the stranded would be slightly bigger -- because
of the inherent inefficient of "packing circles" -- ie, gaps between
non-touching parts of a circle.

If the NEC determines gauge based on diameter, then stranded will have less
ampacity than solid, for the same circle-packing reason -- less net CSA of
copper.

So, how DOES the NEC define "gauge"?

I believe the NEC uses AWG, which uses total cross section.

"Pete C." wrote in message
ster.com...

Existential Angst wrote:

Awl --

Apropos of the recent thread on wire nutting stranded with solid, are
there
any inherent advantages of one over the other? #14-#10.

Stranded is more flexible, an advantage if you have to pull long runs in
bends in EMT, but I find it a pain when connecting outlets, etc.

Stranded can be dicey-er with nicks, missing strands.
But, stranded might give more contact area under screws, in breakers,
etc.

At HD, stranded is $5 more on 500 ft coil of 14 and 12: $25 to $30, and
$40
to $45.

BX/romex comes which way? Both?

Who uses what and when?
--
EA

Like everyone else said, stranded for flexibility pulling through
conduit and whatnot. For termination at receptacles and the like, get
the back wire type devices, not to be confused with the push wire type
which suck. The back wire have a hole you stick the wire in and then
tighten the screw which clamps the wire solidly. This is similar to
terminals in plugs and works well with stranded wire.

Those are fantastic outlets/switches! I don't know if HD carries these --
do they?
I'm sure they are much more expensive than yer 50c HD stuff. The few I've
seen looked really high quality.
--
EA

Existential Angst wrote:
....

So, how DOES the NEC define "gauge"?

It references AWG which is wire area for either.

--

Existential Angst wrote:

"Pete C." wrote in message
ster.com...

Existential Angst wrote:

Awl --

Apropos of the recent thread on wire nutting stranded with solid, are
there
any inherent advantages of one over the other? #14-#10.

Stranded is more flexible, an advantage if you have to pull long runs in
bends in EMT, but I find it a pain when connecting outlets, etc.

Stranded can be dicey-er with nicks, missing strands.
But, stranded might give more contact area under screws, in breakers,
etc.

At HD, stranded is $5 more on 500 ft coil of 14 and 12: $25 to $30, and
$40
to $45.

BX/romex comes which way? Both?

Who uses what and when?
--
EA

Like everyone else said, stranded for flexibility pulling through
conduit and whatnot. For termination at receptacles and the like, get
the back wire type devices, not to be confused with the push wire type
which suck. The back wire have a hole you stick the wire in and then
tighten the screw which clamps the wire solidly. This is similar to
terminals in plugs and works well with stranded wire.

Those are fantastic outlets/switches! I don't know if HD carries these --
do they?
I'm sure they are much more expensive than yer 50c HD stuff. The few I've
seen looked really high quality.
--
EA

Yes, you can find them at 'Depot / Lowe's. They are typically the "Spec"
grade devices and a few dollars each vs. under a dollar. The entire
construction is better than the cheapos, better terminals, better
receptacle contact area and pressure and better more durable body. For a
given project the better receptacles will cost you and extra $20-$30,
pretty negligible for the significantly better parts.

Bob Villa wrote:
On Nov 13, 5:44 am, "Hustlin' Hank" wrote:
On Nov 12, 10:07 pm, "Existential Angst"
wrote:



Awl --
Apropos of the recent thread on wire nutting stranded with solid, are there
any inherent advantages of one over the other? #14-#10.
Stranded is more flexible, an advantage if you have to pull long runs in
bends in EMT, but I find it a pain when connecting outlets, etc.
Stranded can be dicey-er with nicks, missing strands.
But, stranded might give more contact area under screws, in breakers, etc.
At HD, stranded is $5 more on 500 ft coil of 14 and 12: $25 to $30, and $40
to $45.
BX/romex comes which way? Both?
Who uses what and when?
--
EA
I know most of you are talking for home use, but never use solid where
where are a lot of vibrations such as cars, boats and planes. Solid
will break, whereas stranded won't.

Hank

No one mentioned the fact that stranded wire, at the same diameter,
can carry more current.

I won't get into that.

And you could tin the ends of stranded for termination.

By doing so you take away flexibility of the stranded wire so right at
your connection it is more likely to fail. As much as I hate crimped on
wire connectors and always believed soldered was better than connectors,
where there is a lot of vibration they do last much longer than soldered
on wires. Can someone check with NASA?

"Pete C." wrote in message
ster.com...

Existential Angst wrote:

"Pete C." wrote in message
ster.com...

Existential Angst wrote:

Awl --

Apropos of the recent thread on wire nutting stranded with solid, are
there
any inherent advantages of one over the other? #14-#10.

Stranded is more flexible, an advantage if you have to pull long runs
in
bends in EMT, but I find it a pain when connecting outlets, etc.

Stranded can be dicey-er with nicks, missing strands.
But, stranded might give more contact area under screws, in breakers,
etc.

At HD, stranded is $5 more on 500 ft coil of 14 and 12: $25 to $30,
and
$40
to $45.

BX/romex comes which way? Both?

Who uses what and when?
--
EA

Like everyone else said, stranded for flexibility pulling through
conduit and whatnot. For termination at receptacles and the like, get
the back wire type devices, not to be confused with the push wire type
which suck. The back wire have a hole you stick the wire in and then
tighten the screw which clamps the wire solidly. This is similar to
terminals in plugs and works well with stranded wire.

Those are fantastic outlets/switches! I don't know if HD carries
these --
do they?
I'm sure they are much more expensive than yer 50c HD stuff. The few
I've
seen looked really high quality.
--
EA

Yes, you can find them at 'Depot / Lowe's. They are typically the "Spec"
grade devices and a few dollars each vs. under a dollar. The entire
construction is better than the cheapos, better terminals, better
receptacle contact area and pressure and better more durable body. For a
given project the better receptacles will cost you and extra $20-$30,
pretty negligible for the significantly better parts.

AND, easier to attach a wire to, and a more reliable attachment.
Proly actually cheaper, from a net cost (labor) pov.

Push-wire devices ought to be made illegal. Fires waiting to happen, imo.
Esp. push-wire devices used with stranded! That *has* to be illegal, no?
--
EA

Pete C. wrote:
Like everyone else said, stranded for flexibility pulling through
conduit and whatnot. For termination at receptacles and the like, get
the back wire type devices, not to be confused with the push wire type
which suck. The back wire have a hole you stick the wire in and then
tighten the screw which clamps the wire solidly. This is similar to
terminals in plugs and works well with stranded wire.

Very good advice.

"Tony" wrote in message
...
Bob Villa wrote:
On Nov 13, 5:44 am, "Hustlin' Hank" wrote:
On Nov 12, 10:07 pm, "Existential Angst"
wrote:



Awl --
Apropos of the recent thread on wire nutting stranded with solid, are
there
any inherent advantages of one over the other? #14-#10.
Stranded is more flexible, an advantage if you have to pull long runs
in
bends in EMT, but I find it a pain when connecting outlets, etc.
Stranded can be dicey-er with nicks, missing strands.
But, stranded might give more contact area under screws, in breakers,
etc.
At HD, stranded is $5 more on 500 ft coil of 14 and 12: $25 to $30, and
$40
to $45.
BX/romex comes which way? Both?
Who uses what and when?
--
EA
I know most of you are talking for home use, but never use solid where
where are a lot of vibrations such as cars, boats and planes. Solid
will break, whereas stranded won't.

Hank

No one mentioned the fact that stranded wire, at the same diameter,
can carry more current.

I won't get into that.

And you could tin the ends of stranded for termination.

By doing so you take away flexibility of the stranded wire so right at
your connection it is more likely to fail. As much as I hate crimped on
wire connectors and always believed soldered was better than connectors,
where there is a lot of vibration they do last much longer than soldered
on wires. Can someone check with NASA?


If a correctly designed crimp tool is used, crimp connectors are extremely
secure. Unfortunately, it's practically impossible to find a correctly
designed crimp tool in big box stores or local hardware stores.

Existential Angst wrote:

Push-wire devices ought to be made illegal. Fires waiting to happen, imo.
Esp. push-wire devices used with stranded! That *has* to be illegal, no?

UL: "14 AWG solid copper wire only."

--
bud--

On 11/13/2009 6:39 AM Pete C. spake thus:

Existential Angst wrote:

Apropos of the recent thread on wire nutting stranded with solid,
are there any inherent advantages of one over the other? #14-#10.

Like everyone else said, stranded for flexibility pulling through
conduit and whatnot. For termination at receptacles and the like, get
the back wire type devices, not to be confused with the push wire type
which suck. The back wire have a hole you stick the wire in and then
tighten the screw which clamps the wire solidly. This is similar to
terminals in plugs and works well with stranded wire.

You've made a convert out of me. From now on I'm going to use those
receptacles, instead of the el cheapo wrap-the-wire-around-the-screw types.


--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?

- harvested from Usenet

Tony wrote:
Bob Villa wrote:


And you could tin the ends of stranded for termination.

By doing so you take away flexibility of the stranded wire so right at
your connection it is more likely to fail. As much as I hate crimped on
wire connectors and always believed soldered was better than connectors,
where there is a lot of vibration they do last much longer than soldered
on wires. Can someone check with NASA?

Suppose I wanted to replace an 18-gage lamp cord. If it had 19 strands
of 30-gage, like much automotive wire, it would probably screw down to
the socket pretty well. But 18-gage lamp cord may have 41 strands of
34-gage. Twelve-gage zip cord could be worse; it might have 65 strands.

It can be hard to get wire with a lot of strands to stay under a screw.
What would be wrong with tinning? Within the lamp, strain and
vibration shouldn't be problems.

If instead of a screw terminal, I wanted to use a wire nut on zip cord
with a lot of strands, I might try tinning if I had trouble. I wonder
if that would violate the NEC. (Some wire nuts will screw down far
enough to clamp the insulated part of a cord.)

In article ,
David Nebenzahl wrote:

On 11/13/2009 6:39 AM Pete C. spake thus:

Existential Angst wrote:

Apropos of the recent thread on wire nutting stranded with solid,
are there any inherent advantages of one over the other? #14-#10.

Like everyone else said, stranded for flexibility pulling through
conduit and whatnot. For termination at receptacles and the like, get
the back wire type devices, not to be confused with the push wire type
which suck. The back wire have a hole you stick the wire in and then
tighten the screw which clamps the wire solidly. This is similar to
terminals in plugs and works well with stranded wire.

You've made a convert out of me. From now on I'm going to use those
receptacles, instead of the el cheapo wrap-the-wire-around-the-screw types.

Yeah, they're OK, but be forewarned: For solid wire, you have to torque
the living **** out of that clamp screw if you want to end up with a
connection that's more reliable than the infamous backstab. I installed
several of those in my g.f.'s old house, and the mere folding of the
wires as I pushed the receptacle back into their boxes readily loosened
several, even when I thought I had the clamps plenty tight.

E Z Peaces wrote:
Tony wrote:
Bob Villa wrote:


And you could tin the ends of stranded for termination.

By doing so you take away flexibility of the stranded wire so right at
your connection it is more likely to fail. As much as I hate crimped
on wire connectors and always believed soldered was better than
connectors, where there is a lot of vibration they do last much longer
than soldered on wires. Can someone check with NASA?

Suppose I wanted to replace an 18-gage lamp cord. If it had 19 strands
of 30-gage, like much automotive wire, it would probably screw down to
the socket pretty well. But 18-gage lamp cord may have 41 strands of
34-gage. Twelve-gage zip cord could be worse; it might have 65 strands.

It can be hard to get wire with a lot of strands to stay under a screw.
What would be wrong with tinning? Within the lamp, strain and
vibration shouldn't be problems.

If there isn't a vibration or strain problem, then there is no problem
that I see.


If instead of a screw terminal, I wanted to use a wire nut on zip cord
with a lot of strands, I might try tinning if I had trouble. I wonder
if that would violate the NEC. (Some wire nuts will screw down far
enough to clamp the insulated part of a cord.)

If I am joining zip cord, or stranded wire in a light fixture to 14
solid, I just strip the stranded wire longer than the solid wire and
twist it around the solid wire first, then add the wire nut. It's
always worked _great_ for me. I do make sure there is more of the
stranded wire toward the end of the solid, it's just how I found it to
work the best. Maybe it's not code if I strip the stranded wire longer
than the strip gauge? I don't know. I do know that it works very well
code or no code. Give it a try and you won't have to worry about tinning.

On 11/13/2009 5:51 PM Smitty Two spake thus:

In article ,
David Nebenzahl wrote:

You've made a convert out of me. From now on I'm going to use those
receptacles, instead of the el cheapo wrap-the-wire-around-the-screw types.

Yeah, they're OK, but be forewarned: For solid wire, you have to torque
the living **** out of that clamp screw if you want to end up with a
connection that's more reliable than the infamous backstab. I installed
several of those in my g.f.'s old house, and the mere folding of the
wires as I pushed the receptacle back into their boxes readily loosened
several, even when I thought I had the clamps plenty tight.

So are they really more reliable? Sounds like they might not be. (Or
perhaps not without the required torque screwdriver?)


--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?

- harvested from Usenet

On Fri, 13 Nov 2009 19:18:22 -0500, E Z Peaces
wrote:

Tony wrote:
Bob Villa wrote:


And you could tin the ends of stranded for termination.

By doing so you take away flexibility of the stranded wire so right at
your connection it is more likely to fail. As much as I hate crimped on
wire connectors and always believed soldered was better than connectors,
where there is a lot of vibration they do last much longer than soldered
on wires. Can someone check with NASA?

Suppose I wanted to replace an 18-gage lamp cord. If it had 19 strands
of 30-gage, like much automotive wire, it would probably screw down to
the socket pretty well. But 18-gage lamp cord may have 41 strands of
34-gage. Twelve-gage zip cord could be worse; it might have 65 strands.

It can be hard to get wire with a lot of strands to stay under a screw.
What would be wrong with tinning? Within the lamp, strain and
vibration shouldn't be problems.

If instead of a screw terminal, I wanted to use a wire nut on zip cord
with a lot of strands, I might try tinning if I had trouble. I wonder
if that would violate the NEC. (Some wire nuts will screw down far
enough to clamp the insulated part of a cord.)


Just "hard twist" the wire and you are usually OK. IF you solder the
end, make sure there is a strain relief close to the connection to
prevent flexing of the wire near the soldered end.

David Nebenzahl wrote:

On 11/13/2009 5:51 PM Smitty Two spake thus:

In article ,
David Nebenzahl wrote:

You've made a convert out of me. From now on I'm going to use those
receptacles, instead of the el cheapo wrap-the-wire-around-the-screw types.

Yeah, they're OK, but be forewarned: For solid wire, you have to torque
the living **** out of that clamp screw if you want to end up with a
connection that's more reliable than the infamous backstab. I installed
several of those in my g.f.'s old house, and the mere folding of the
wires as I pushed the receptacle back into their boxes readily loosened
several, even when I thought I had the clamps plenty tight.

So are they really more reliable? Sounds like they might not be. (Or
perhaps not without the required torque screwdriver?)

The trick here, when using them with solid wire, is to wiggle the wire a
bit while tightening to ensure that it is seated at the far edge of the
clamp. What happened in the example, is that the wire was initially
clamped in near the screw and with the clamp plate at a bit of an angle,
the wire wiggled out to the wider edge area. If you endure it has
settled to that area when you are clamping it there isn't a looser area
for it to shift to. You can see the same thing happen if you try
clamping a solid wire in a plug that has the contacts visible.

Pete C. wrote:
David Nebenzahl wrote:
On 11/13/2009 5:51 PM Smitty Two spake thus:

In article ,
David Nebenzahl wrote:

You've made a convert out of me. From now on I'm going to use those
receptacles, instead of the el cheapo wrap-the-wire-around-the-screw types.
Yeah, they're OK, but be forewarned: For solid wire, you have to torque
the living **** out of that clamp screw if you want to end up with a
connection that's more reliable than the infamous backstab. I installed
several of those in my g.f.'s old house, and the mere folding of the
wires as I pushed the receptacle back into their boxes readily loosened
several, even when I thought I had the clamps plenty tight.
So are they really more reliable? Sounds like they might not be. (Or
perhaps not without the required torque screwdriver?)

The trick here, when using them with solid wire, is to wiggle the wire a
bit while tightening to ensure that it is seated at the far edge of the
clamp. What happened in the example, is that the wire was initially
clamped in near the screw and with the clamp plate at a bit of an angle,
the wire wiggled out to the wider edge area. If you endure it has
settled to that area when you are clamping it there isn't a looser area
for it to shift to. You can see the same thing happen if you try
clamping a solid wire in a plug that has the contacts visible.

My brother who is a licensed electrician with his own company hangs out
on some newsgroup for electricians. He told me long ago that there is
an ongoing debate there about using the same gauge wire on each side of
the screw for the reasons above. Most of them say it is code, and
against code to use only one side of the clamp.

In article .com,
"Pete C." wrote:

David Nebenzahl wrote:

On 11/13/2009 5:51 PM Smitty Two spake thus:

In article ,
David Nebenzahl wrote:

You've made a convert out of me. From now on I'm going to use those
receptacles, instead of the el cheapo wrap-the-wire-around-the-screw
types.

Yeah, they're OK, but be forewarned: For solid wire, you have to torque
the living **** out of that clamp screw if you want to end up with a
connection that's more reliable than the infamous backstab. I installed
several of those in my g.f.'s old house, and the mere folding of the
wires as I pushed the receptacle back into their boxes readily loosened
several, even when I thought I had the clamps plenty tight.

So are they really more reliable? Sounds like they might not be. (Or
perhaps not without the required torque screwdriver?)

The trick here, when using them with solid wire, is to wiggle the wire a
bit while tightening to ensure that it is seated at the far edge of the
clamp. What happened in the example, is that the wire was initially
clamped in near the screw and with the clamp plate at a bit of an angle,
the wire wiggled out to the wider edge area. If you ensure it has
settled to that area when you are clamping it there isn't a looser area
for it to shift to. You can see the same thing happen if you try
clamping a solid wire in a plug that has the contacts visible.

Thanks, Pete. Next time I'm going to try that; it sounds logical. I work
with similar clamps in machine chassis wiring at work, where it's easy
to see the designated wire channel detent.

Tony wrote:
E Z Peaces wrote:



If instead of a screw terminal, I wanted to use a wire nut on zip cord
with a lot of strands, I might try tinning if I had trouble. I wonder
if that would violate the NEC. (Some wire nuts will screw down far
enough to clamp the insulated part of a cord.)

If I am joining zip cord, or stranded wire in a light fixture to 14
solid, I just strip the stranded wire longer than the solid wire and
twist it around the solid wire first, then add the wire nut. It's
always worked _great_ for me. I do make sure there is more of the
stranded wire toward the end of the solid, it's just how I found it to
work the best. Maybe it's not code if I strip the stranded wire longer
than the strip gauge? I don't know. I do know that it works very well
code or no code. Give it a try and you won't have to worry about tinning.

Now I remember where I've tinned stranded wi speaker wire! Some
small-gage speaker wire has very fine strands. Tinning the ends makes
it easier to insert it into the terminal on a receiver or speaker.

I discovered that the tinned ends made it easier to use wire nuts on
speaker wire. I've also tinned stranded wire in electronics where I
wanted to use a wire nut for a connection that could be done and undone
as easily as a plug.

I've never tried this in a 120V circuit. I don't know if there would be
drawbacks.

Most of my connections using stranded conductors are in vehicles, and
the strands are usually stiff enough that I don't need pretwisting. It
depends on the design of the wire nut. I try to screw the wire nut down
onto the insulation for mechanical reliability.

Like you, I'll pretwist if the strands are so flexible that they get
pushed out of the way of a wire nut. I use about 1/2 turn CCW. The
wire nut twists the bundle CW, and the pretwist gives the wire nut a
head start on that twisting.

I've used a wire nut on conductors whose strands were silky thin. It
was the cord of a set of headphones, which I accidentally snipped with
pruners. There were three conductors: left, right, and ground. I
"spliced" each conductor by pinching it in a piece of masking tape, then
screwed a live-spring wire nut over the whole thing.

The wire nut provided electrical reliability by squeezing the taped
connections. It helped mechanically by clamping the insulated cords
together. I've used those mended phones for ten years without trouble.
Wire nuts can be very useful!

Tinning the ends of stranded is an excellent idea -- proly no one does
it,
tho.
It is actually a BAD idea, as it hardens the wire where the tinning
stops, making the wire more succeptible to fatigue breaking of the
strands. NOT ALLOWED in aircraft wiring, for one "solid" example.

Please say more.

Wiring a lamp socket, tinning just the last 1/4th or 1/8th of an
inch, just to keep the strands from sticking out from where screwed
down, surely that's ok?

And being screwed down hard, no flexing, I'd hope.

Seems to me that a strand coming loose within airplane wiring
would be a lot more dangerous than tinning just a tiny bit
at the end to keep a strand from sticking out, with who knows what
effects.

Now, I am willing to be educated. Please don't just dictate
the correct answer, but try to CONVINCE us via argument,
data, metallurgy, whatever.

THANKS!

David


Worked at wiring broadcast studios, and we were not allowed to tin stranded
wires..
It was said that solder is too soft, and after tightening down screws or
clamps, the solder would just compress,
and would eventually cause a loose connection.

Ray

we are factory since 1983. if you need cable making machine,like laying-up machime. take-up and pay-off equipment, pls tell me.cablemachinery at 126 dot com