I’m starting to build my own sensors with the ESP… I’m using the same pin cables that I can buy on Alixpress. I cut the connectors, peel them, tin them and connect them between sensors and controllers. I wanted to know if it would be better to use special cables for these projects. Sometimes stripping the cables could lead to cutting some small wires… are there any safer cables, perhaps made up of a single wire?
thanks
I make mine out of old cat5 cable most times. Every 1m of cat5 will yield 8x1m colour coded cables, and I usually have some at hand in a drawer somewhere.
Go for solid cat5 if you’re wary of cutting up the stranded version (not that it would matter if you have a proper stripper). Just make sure it’s actually copper - stay away from anything labelled as CCA.
This is a good idea. I was wondering the same as op.
Hi,
I will just give a feedback of my experience about UTP. No offense @ShadowFist 
A UTP cable is not the best for soldering. It can break very easily if you damage (even a little) the core. Cat5 (mostly AWG26) and is very thin. A UTP cable is generally made to be crimped.
If you use solid (mono-strand) wire, it will generally need a anti-traction system otherwise it will most probably break.
The best for soldering is multi-strand wires but if they are “pure” copper, you will have to tin them but it may melt the insulation/sheath. So the best is pre tinned wire.
Now to come back to your initial question. I maybe did not understand your project so I need more details. If this is just to do some test on your workbench, go for the UTP cable as @ShadowFist suggest as it will be the cheapest and the easiest
If you need to install you sensor in your house and wire them upto the technical room, it is important to know what kind of signal/data/protocol/speed will transport the wires
How are you connect your sensors in bus (they are chained/connected one after the others) or is star (each sensor come back to the ESP)
Best regads
ps: I do not know all the rules of the forum but it is also useful, great to give references or link of materials you are talking about (I meant for sensors and aliexpress wires )
they are small home inspection projects. I’ll give you some examples. An ESP32 c mini and an LD2420 radar sensor. An ESP32 and an I2S MP441 microphone with a speaker for Voice Assistant. A power supply connected to my ESP32 for power. Some of these, I have to put them inside little boxes and the cables will be curved, bent, crushed (some more, some less).
Should I use different cables for each type of transmission?
Personally I would like the best type of cable possible in terms of resistance, capacity and speed or in any case the best in terms of the relationship between these aspects…
I am preparing and creating many projects including presence sensors, voice assistants, temperature, displays etc. so I should find the most suitable solution.
Here in the photo is the simplest project to put in a little box (I don’t use much force, I try to pull them a little, but they still seem quite firm)
and these are the common cables you can buy from alixpress:
On the last picture, it is a good idea to keep Vcc away from data to avoid interference/noises if you VCC is not clean. Often, power supply from USB connector is fed to a DC/DC converter that can generate interference/noise on VCC if it is not correctly filtered.
If you put your board in a tight box, the best is the mono-strand wire (like UTP). It seems you used multi-strand wire which is normally good for “flying” boards as they will lead to less forces at junction/soldered ends but in a tight box, the best is mono-stranded wire as you can give them the best shape and prevent any forces at both ends. (Even if it seems so, I do not say the opposite of my initial post ). It is just a more specific use case on mono-strand wire.
But keep in mind that mono-strand wire will break if you box and unbox too much time your boards from box and you move them apart of each others too often. You will bend and unbend mono-strand wire at the solder point that will break after some times because generally, you will go from 0° and 90° angle several times and copper wire are not meant for this.
Generally, I2S is used directly on board (so using tracks) or using flat flexible cable to interconnect master and slave boards. So the standard does not provide any recommandation for wiring.
[…] The I²S connection was not intended to be used via cables […] There is no standard interconnecting cable for this application. Some manufacturers simply provide three BNC connectors, an 8P8C (“RJ45”) socket or a DE-9 connector. Others like Audio Alchemy (now defunct) used DIN connectors. PS Audio, Musica Pristina and Wyred4Sound use an HDMI connector.[7] Dutch manufacturer Van Medevoort has implemented Q-link in some of its equipment, which transfers I²S over 4 RCA connectors (data, MCK, LRCK, BCK).
source: wikipedia
What do you mean by “each type of transmission” ? Different protocols I2S/I2C/SPI ? If it is I2C, SPI and I2S are generally used directly on boards and boards are connected using flat cables, tracks or pin header (with gold contact to have less oxidation and a low resistance). Indeed, gold contacts have a smaller resistance (they conduct better) than a tin solder.
You may encountered some glitches if your soldering is bad/cold or if there is too much distance between boards but this is not your case. Everything should work as expected.
I hope this helps
If you need to bend and move the wiring many times, better to use stranded wire.
Like you can see on your image, the cheapest AE cables have next to nothing copper inside.
Use something like 24 AWG.
I really like working with silicone wire. The flexibility really helps with tidy routing, especially in small enclosures.
Sometimes I hotglue on / near soldered joints after testing to provide strain relief.
Another vote for that.
Which AWG?
There are two schools here between mono and multi-stranded wire 
So the final word will be : “make your own experience/opinion” based on all good/valid advises here". This is finally the best school
As current (power) is not important here, based on cable you already have, take sections that you like the most. Bigger AWG will be more fragile, smaller AWG will take more place and may be more difficult to arrange/bend in the box.
I’m no AWG guru. I switch it up a little depending on the length I need. Sometimes I go thicker for shared grounds and power.
The 30AWG is on the thin side (I believe), but it’s what seems to come in those multicoloured kits I showed and seems to work just fine for short runs.
No clue how good practice the above is but seems to work for me.
I don’t think it’s just a matter of flexibility and space the AWG… I also think it’s a matter of cable length. If you need a longer cable I think it’s best to choose a small AWG (i.e. the largest cable). What you need to understand… is the question of operation. Because OK, space and flexibility but the important thing is also that the data is transmitted correctly and there is not too much resistance.
For power… on a couple of meters of cable with 5V, 24AWG can be fine?
I honestly don’t even know what section AWG is… normally I’m used to thinking in mm2.
Very much on that side. Totally ok for signal wires, but there is not much “consistency” to work with. And if you want to use it for powering something, go with 22 - 26 AWG.
depends also distance… and the Amps you need
Of course. My point was to get something “universal” for signals and low power supply.
Don’t think of supplying 10A motor with 24 AWG wires.
the reason for all these questions…
there is always something wrong with our projects… and the questions are always many:
I happened to try using an ESP32 and an I2S MP44 microphone… after having connected everything correctly and working I tried to replace the microphone cable with a 20cm one (double) and indeed the microphone did not work anymore.
Now since I had already lost many hours to put everything together without asking myself too many questions I went back to the old shorter cable and bye.
Having a basic understanding of the possibilities can still increase the chances of success and reduce wasted time. I also have an application that allows me to calculate sections and lengths and any voltage losses… but I use it mainly with AC but I need more in-depth knowledge on DC.
Thinking about it more, I think that’s what I basically do.
I buy dedicated black/red rolls since you use a lot more of that and get a few thicker AWGs.
Then I use my coloured 30AWG for short signal wire runs (~3 to 15cm) . For longer runs (which for me is still typically just 1-2m) I often cut reuse something like a usb cable.
If I need longer power cables I either use my thicker AWG or reuse/cut some power cord I have.
Thumbs up for @Mahko_Mahko silicon multi-strand spool boxes. I have a few different gauge. Use only for soldering and wiring in boxes. Tips all tinned and soldered. Never ever used a breadboard and so far never had a dud connection. If you know how it should be done then get on with proper connections! 
Longer runs outside my boxes is usually cat6a double insulated. However, network cabling needs to be considered, increase in capacitance can be a problem where data transmission is clock dependent. Horses for courses. 
