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What are the advantages of stranded vs solid wire?

what should i be using for prototyping circuits?

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10 Answers

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Solid wire (24 gauge) is good for use as jumpers in solderless breadboards. Trying to push in stranded wire is frustrating. Solid wire holds its shape, so you can route wires along a path and they'll stay there.

Use stranded wire for everything else. It is flexible so it's good for cables going between a circuit board and knobs/switches on an enclosure, connecting cables between circuit boards, or any time you might have physical flexing in a wire. 24 gauge is a good all-around size for stranded too.

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Advantages

Stranded-More Flexible,

Non-Stranded-Easy to solder, will fit into breadboard. Trying to insert stranded into a breadboard is like trying to push string!

I prefer non stranded, in fact I have a good tip here for a cheap source.

Buy Solid Core Cat 5 or 6 Network cable, a couple of meters goes a long way...

Strip it out and you get 8 differently coloured/marked sets of good quality cable in 4 twisted pairs. Very cheap compared to buying hookup cable in small quantities, and generally better quality!

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I think "Trying to insert non-stranded into a breadboard is like trying to push string!" should actually say stranded. – Amos Nov 24 at 10:09
I am not sure what you mean, stranded is by far easier to solder in projects. There are certain situations where non-stranded is easier, but stranded gets better contact and better joints. – Kortuk Nov 24 at 14:17
The full paragraph says: "Non-Stranded-Easy to solder, will fit into breadboard. Trying to insert non-stranded into a breadboard is like trying to push string!" This is contradictory, either non-stranded is easy to fit into a breadboard or it's like pushing string. From experience I would say that stranded is more like pushing string than not, hence my comment. – Amos Nov 24 at 14:55
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the wire in cat-5 cables is very small (maybe 22-24 gauge?). This is great if you are soldering, but if you stick it in a breadboard it pops out very easily. – jkopel Nov 24 at 18:09
Corrected non-stranded comment, late night posting is never a reat idea! I personally have found stranded cable more difficult to solder. In terms of it popping out of breadboard, Again not in my experiance. – Justblair Nov 24 at 22:41
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As todbot says, if you are prototyping on a breadboard then solid core is easier. Except that when you are making connections between the breadboard and something else (like a sensor, or an Arduino, or another breadboard) the wires tend to jump out of the breadboard. The solution is to use flexible stranded wire for those runs, and solder a single pin from a male header on each end to make jumpers. A short piece of shrink wrap will provide some strain relief and keep the pins from breaking off. You can also buy these jumper wires pre-made from adafruit or sparkfun, but they are easy to make.

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Adafruit and Sparkfun have some excellent cables with the pins already on the end. $7/100 is pretty darn cheap - I use them whenever I'm going between boards. – edebill Nov 24 at 17:48
+1 for pin headers. Cables for them are also easy to come by if you have a source for junk PC's as they're full of them :) – XTL Jun 29 at 5:54
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One thing I have not seen mentioned is that solid wire (when bent many many times) is more likely to break than stranded wire.

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I agree, but we are talking a lot of bending... I can think of situations where this can be a problem, but not so much at a the prototyping stage – Justblair Nov 24 at 22:46
I had a broken wire in a digital circuit I did that drove me crazy. I took apart and rewired the whole thing three times and the problem kept moving. – Shawn J. Goff Nov 28 at 16:56
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Most connectors are designed to be used for stranded wire. Crimp tools in particular are often precision-machined and are not guaranteed to work properly on solid-core wire.

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Good point. While its not impossible to crimp onto solid core cable, even when extra care has been made to provide strain relief the termination can be fragile... – Justblair Nov 25 at 7:35
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It depends...if you are wiring up 100 connections, you really want to use stranded wire, since you can get it thinner and more flexible. If it's just a few connections, thicker non-stranded wire is easier to deal with.

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If you tin stranded wire, it'll work well enough in a breadboard. I often do this as I build up components (like a remote sensor) and prototype/test each piece along the way.

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But why bother? For that kind of work, non-stranded wire is cheap and somtimes the additional stiffness adds to the ease of use... – Justblair Nov 24 at 22:43
I was referring to the remote sensor as a finished product. Say I want to put a photodiode and op-amp on protoboard, but then plug that component into my breadboard as I build the bigger system. I'd use stranded wire connected "permanently" to the protoboard, and tin the other end for use with the breadboard. – blalor Nov 25 at 21:49
Yes that would be a pretty sensible thing to do under the circumstances – Justblair Nov 26 at 6:59
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When it comes to network installations (such as CAT5 in-wall) solid wire is the way to go, provided the wire is not intended to move, such as in a B&M business or a home. In the marine industry they use stranded wire for everything, as even at rest the boat moves and flexes.

Patch cables are made with stranded wire as its intended to move around.

Basically its much easier to breadboard with solid wire, but easier to prototype (solder) with stranded.

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I think, it depends on the project 100%. For example, attempting to solder stranded on to a diode... you either pop the diode or get too mush soldier. When using diodes... I always use solid core... same with capacitors etc...

Stranded works when you can crimp onto large diodes like the old Germanium types. But the newer High Output Diode does not like to be crimped... it needs all the electrons it can get.

Stranded is for 'handling' or 'the monkey principle'. If you plan to lay the wire once and forget it in a place where very little vibration occures, then solid is the way to go, the variance will not change over time as the wire oxidizes. Stranded cable because of the tiny bits of air that surround the strands, will oxidize much faster and in maybe 3 years, it will be brown and lacking conductivity.

Same with 'tinning' on small component type circuits. You don't want to change the behavior of the electrons as they flows. There is a reason we moved away from Tin wire Heavily used up until say 1985 or so... it would become brittle and in a lot of cases degrade the copper so that you would get pitting between the tin and copper. But still today, professors and engineers who earned their degrees in prior to say 1990 or 1995 are taught that tinning has a positive effect. Like Marconi invented the Radio or Edison invented the Light bulb. They teach this as 'right'. There is a reason why Cu is far away from Sn. Germanium vs Silicon... I remember my micorprocessor professor swearing Germanium will out live Silicon as the semi-conductor of the future. That is where we are with Tinning wire. Stranded vs Solid core applications for wire. If it was better then modern engineers would insist on tinned stranded cable... but we know they prefer the purist copper cable they can find for their applications.

Stranded vs Solid Core wire arguments - Stranded wire good for only applications where heavy vibrations would crack a solid core wire (I have no idea what that would be, the wire would have to be strung pretty tight)

  • Lots of handling (monkey principle)
  • cheaper for industry to to install and forget, there is a huge market for replacement LED's for Marine equipment because of outdated engineering data REQUIRES stranded core wires... and engineers have to use the old Germanium LED's so they can meet this standard... (wave my magic wand: "ridiculous") Maybe this made sense when we had locomomitive engines driving boats... Have you been on a boat lately, they are built like Rolls Royces... same with cars... when was the last time you sat in a new car and you thought, man I hope it holds together long enough to drive it off the lot?

  • How much vibration is needed (even over a long time to break a 24AWG wire?)

  • Lots of bending back and forth... like installed on a moveable arm or some moveable device... but bending around lots of corners is not a good enough excuese.

[I remember a study about stranded vs Solid core about which one would heat up and break faster when bent at 45 degrees but, I forget what the out come was]

[CAT 5 has been in buildings since... 1994/5 (earlier?) and is now after 15 years starting be replaced on a massive scale by CAT 7 and fiber. If stranded was better, engineers would have switched to it long ago.]

Breadboard technology - CAT 5 comes in 22AWG to 24AWG - 24AWG holds firmly unless you have plugged house wire into the holes ;-P. Or larger than 24AWG - like 20AWG wire will fit in the breadboard and 'electronic' kits come with 20AWG and will stretch out a breadboard. Expiriment - get new board and plug different size wires into holes and see which ones stretch out the holes.

  • oh well, this MIT grad has worn himself out here... but I enjoyed reading peoples responses... and the 'war' continues over Stranded vs Solid core ... your biggest rival SAE and ABYC are very outdated... as is UL... and the IEEE and ISO. They were great when they were young, but good jobs create a need for job security and it is easier to go with 'what you know' even if that is not the 'best' way to go. In a way it makes sense.
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These are great for solderless breadboards: http://www.littlebirdelectronics.com/products/Jumper-Wires-Premium-12%22-M%7B47%7DM--Pack-of-10.html

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