I am working on a project that I want to divide into three modules: the main power and Arduino control module, a module with a stepper motor and sensors, an optional module with solenoids and sensors.
I was thinking that I might be able to use D-sub connectors to run power and signals back and forth between the different modules (I would have to make sure that it's a shielded cable to make sure that the signals don't get messed up). There shouldn't be anything that runs more than 1.8A, and D-sub looks like it can do 3A, so I should be fine there.
I'm working with breadboard right now, so I was hoping to find a D-sub connector that I can connect jumper wires to. I found some PCB mount connectors, but I can't find the pin diameter. Does anyone know what size these pins are and whether or not you can use standard jumper wires to connect to them?
What made you consider D-sub connectors? They're not particularly easy to use and are kind of a pain to mount to a panel. And before you get into the details of shielded cables, make sure your signals actually need to be shielded.
When in doubt, I go for some kind of circular connector: plentiful, available at all densities and price points and it's pretty easy to drill a round hole.
That is a great point. I am planning to look at a protoboard or even a custom PCB in the future once I had things working, but I need to get everything working first.
The jumper wires that I have are 26 AWG so should be rated for 2.2A for brief periods, the breadboard that I have been using so far is rated for 1.5A at 36V, and the max draw that I can see in the datasheets of the components is 1.67A at 24V, so I am pushing it a bit with my current equipment. I am planning to order more breadboards for setting up the different modules for the prototyping, and I have found some boards that are rated for 3A at 30V.
A D-subminiature connector, likely 15 pin. The cheaper ones that I can find are rated for 3A and I have seen some that are 5A. The one side of the connector is your standard male or female D-sub pin connector, and the other side can be made to be PCB mounted with pins. I'm wondering if those PCB pins are the right size for connecting jumper wires too.
I was looking at them because I found some in the local electronics store (just not ones with PCM pins), but I am open to suggestions. I am looking at using some DC barrel connectors for connecting some components that are just power in/power out.
There are a few reasons that I was looking at D-sub connectors. For the modules, I am looking at 13 pins for the one at 15 pins for the other (I am not sharing grounds for the different voltages that I am using can essentially create a star ground set-up to try to prevent issues from a common ground). I figured that if I make one connector a standard 15 pin D-sub (i.e., two rows) and the other a high-density 15 pin D-sub (i.e. 3 rows) then anyone else using it in the future won't accidentally connect things in the wrong order. I also figured that the cables are common enough to be relatively easy to find. And when I tried searching searching for 15-pin connectors, I was seeing D-sub connectors everywhere.
For signals, I am going to have some digital and some analogue signals, and they are going in either direction (i.e., some go to the modules, and some return from the modules). I am also expecting a range of voltages from 3.3V for some components to 24V for others. Given this, I figured that it's better to use shielded cables to reduce potential noise in the signals.
If you have any suggestions on alternative connectors that I could use, I'm all ears.
I'm using 26 AWG wires that are rated for 2.2A, and I don't expect to see anything more than 1.67A. I'm also going to be using a breadboard rated for 3A at 30V.
The benefit that standard jumper wires are held on it pins well (straight contacts are thinner and jumpers do not hold on them).
For the connection itself I use a standard IDC type flat-cable:
Power delivery is the most crucial building block in all electronics. If it is sloppy done, all sorts of weird behavior will occur and is usually very hard to track down.
You're already sniffing on the solution, just take the step. A breadboard is not for high currents. Why not solder everything power to a protoboard, and do the logic on the breadboard. Or use a terminal block like this:
I think typically they are 0.6mm, possibly too small for a typical breadboard jumper type female connector.
I have seen many variations of D-sub connector, but never one with breadboard jumper cables. I would suggest those adapter boards is your best bet. There are also breakout board to wire terminals.
The traces on the Breadboard are typically fine for the currents being discussed(but do verify they are wide, not thin), but those adapters may not have traces as wide, so be aware. Often, those header adapters are intended only for logic type signals, not the power wiring the OP is planning on.
The contacts of the Dupont-style jumpers are also suspect for serious currents, because not all jumpers are created equal. For example, some wipe the connection pin on only two sides, as opposed to 4 sides, which reduces contact area and leads to contact heating at higher currents.
The contacts on the Protoboard, I personally would not run more than 1A through; they are also intended for logic signals, not power wiring. I've personally melted these when 'abusing' them with less than an ampere - but this was on an old breadboard, presumably with less-than-pristine contact surfaces.
It's all a YMMV sort of world. I much prefer to make all/most connections carrying significant current using either compression (screw terminals or spring style - like "lever-nuts"), or solder. But, YMMV.
