Resources for wire management?

The next stage of my prototype: mounted on the portable skeleton. See photo.

The approach to wire management was to group the components on separate mini breadboards (as shown in the previous table-mounted circuit), according to their function, in three sectors, in my case:
a) Power Sector - objects: source 3.7 LiIon 18650; DC-DC (3.7 tp 5V)
b) Processing Sector - objects : Arduino nano; LCD 1602 I2C
c) Sensors Sector - objects : logical level translator, DHT22; BMP280
Components are defined as objects and their terminals are marked to the local line (within its sector) each one use.

Each sector has its own local lines:
Power lines:

  1. GND
  2. 3.3 V (if needed)
  3. 5 V
    Data lines:
  4. I2C (2wires)
  5. Digital
    More Digital and Analog local lines can be added.

Each local line is connected to the others in the rest of the sectors.

In this way each sector can be reviewed and checked separately. There is no need for complex diagrams because each sector can only comprise few components.

I found this way as being rewarding in its simplicity.

The diagram drawn according to this concept (which I will post shortly) depicts only local lines and terminals notation.

The only problem is that this structured way of wiring needs more jumpers than the usual one.

If the circuit has to be enhanced this can be done either:
a) by adding more sectors - to the point the Board capacity is reached
b) by adding more processing units in a slave-master configuration

When translating to the perf (which I will do it) then multiple small plates is more configurable than only one big.

There are still improvements to be done, like using straight wires instead of jumpers, develop an intermediary Bread board that phisically separates sectors.

I am late in my project because the supplier changed the LCDs I used so I have to re-code.

**Question is: is somebody aware about alternative ways to draw the circuits apart form the well-known international symbol one? **

20180501_175055[1].jpg

And here you have the structured block diagram.

It is very simple: each sector has its own internal physical lines - as described in the previous post.

From one sector to another, only one wire can pass for each individual internal line. In other words, if there is only one digital wire from the sensor, it cant pass directly to the sector 1 - it shall join the internal data line first. Then, from internal data line one wire pass to sector 1.

At a first sight it looks like excessive use of wires. But the advantages are great when the circuit is tested and when it is extended - either by more objects in one sector or by more sectors.

It is also very clear whether all components share the same ground and are connected correctly to their power or data line.

Structured Block diagram A nano sensors portable device.pdf (829 KB)

I was unable to find here wire-nuts. I can either find an European provider (which is somehow excessive for a 2 dollar purchase) or attempt manufacturing (DiY) them - somehow- any suggestion welcomed!

Why not just order them online? If you would have done so when the topic first came up they would have already been delivered, even from China.

For other suggestions, it might be helpful if you said where you're located.

In my view it is a waste of money to order a 2 USD merchandise that is going to cost 50 USD delivery (or even 20 USD).

Another point is that I may need different types in different quantities, which may result in repeated orders, adding up delivery costs and waiting times.

Here in the US I can buy bags of wire nuts on eBay or Aliexpress for as little as $0.50 for 10 pcs and have them shipped to me for free from China. You can buy collections of assorted sizes or just a specific size. Is the shipping really so expensive where you're at?

falexandru:
I was unable to find here wire-nuts. I can either find an European provider (which is somehow excessive for a 2 dollar purchase) or attempt manufacturing (DiY) them - somehow- any suggestion welcomed!

wire-nuts are for electrical work not for electronics

@ Ted I know. But I want to use them for kids. I leave the wires "on air" like in the old times. Currently, I just teach kids to twist the wires by hand. To many times this operation fails because of wires sliding.

Those wire-nuts would be excellent to replace the twisting. But I want to check this before buying in bigger volumes.

For kids I want big things :-)).

I also invented a sort of tool that twist thin wires around the components terminal. But this is to small for kids :-(.

Thanks for photo!

The push-wire terminal connectors (I think they are called WAGO) I found in the electrical products sector in the hardware store are not designed for high voltage, as far as I understand.

They are very nice to click all wires together but require to much force to operate, exceeding what a kid can do. Still, nice piece of engineering.

I do not know whether WAGO rail mounted connectors are small and cheap enough to use for small circuits.

This is about low temperature soldering. Something 25-47 C as far as I understand.

That may fit work with kids.

But I have no idea about regular (common, hobby) use of this technology. Impressive, though.

the smalest -71B Gray Wire Nut Connector -they are good for above cable, the big will not stay on connected wires

For thin wires - small wire splice connectors

falexandru:
are not designed for high voltage, as far as I understand.

Kids and high voltage ?, safe voltage is 24V

ted:
Kids and high voltage ?, safe voltage is 24V

I wanted to say that the WACO (?) connectors I found are designed for low voltage, but they were placed in the section for 220V in the hardware store. Therefore, I wonder whether some other interesting items are not placed randomly.

For kids, I stay on 3V for general purpose and in 5V for Arduino.

+++

From internet: Europe (where I am located) has safety standards that are easier to fulfill by other connection methods than wire-nuts. This is why they are not available here. Some time ago, a lot of electricity networks were in aluminium and this also prevented the use of wire -nuts.

The interesting point is that I found the wire-nuts (from the description) as very appropriate for low voltage connections - in teaching kids. Because apparently nobody considers this use, it seems like nobody imports them here.

If no hope, I will keep using rabbit-tail twisting ans some insulation band.

For DIY projects connecting aluminium with copper are -screws, and wire nuts, to make join better special compound is used.

They are in europe, but under different names,Poland.

ted:
Wire wrap - Wikipedia

Thank you!

For this operation I invented a tool (to be honest, it does not work very well. but it could be improved :slight_smile: