Cables and connectors for 12VDC

For about the past two years I've been building a hydroponics controller as I can afford to buy all that is related and learning to write the code. External to the main project box is another box that houses eight - 12 volt motors that turns dosing pumps. The boxes will be wall mounted within 3 feet (1 meter) of each other. I am looking for a solution to send either the 12 volts from the motor drivers in the main box, or, the logic voltage from the main box to the motor driver boards in the motor box. I'm open minded to ideas of what would work better for the Arduino, but I also want the end result to be clean and easy to disassemble. I was thinking something that has a lot of pins like HDMI, but am unable to find much info about how it would work with 12 volts instead of 5. Basically, I'm just fishing for ideas.



How much current at 12V??

How many signal conductors?

Cheap 12V high-current (10+ amps) connectors are those used for "Drone" and Model batteries..

A multipole connector like THIS might be good.. These are good for 5 amps as I recall.

DISCLAIMER: Mentioned stuff from my own shop...

I would think that the current carried by the cable and connectors would be more important than voltage in choosing the right wire(s) and connectors. At least at 5 and 12 volt levels. Data sheets for the connectors will have a current rating and wire tables the ratings for different wires.

I would say avoid any long lengths of logic level cables are they will always be more prone to picking up interference and transfering it back to the Ardunio board and causing problems.

If you find it easier to have the mcb with the motors, then use some quality screened cable properly earthed.

This time of year I always think about giving hydroponics a go in the greenhouse and was just searching for some info on simple ways to run it, but seeing your 8 pumps ?!! , wonder how simple it can be ?

What stall current are the motors? Standard brushed DC motors? Do they need to be bidirectional or one-way only?

I had just typed up a very descriptive, but short reply of my setup and when I clicked post, I got a site error message and lost it all, end rant.

In the 3 attached photos, I show the 2 boxes near one another. The outlets box is the control center as it houses an 8 channel relay, an Ethermega mounted to a piece of plexiglass that itself is mounted about 1/2 way into the depth of the box. There is also a long breadboard stuck to the plexi that has plenty of room left that I can add 4 TB6612 motor driver circuits from sparkfun. Each will turn 2 motors. The motors will only ever rotate a single direction so I'm reclaiming an otherwise used pair of pins on the mega per each circuit. I also have another long breadboard to use in the project if I decide to put the motor drivers in the pumps box and import that logic. If I use the drivers in the outlets box, I would then be sourcing out the regulated voltage (PWM).

I must also say that I am planning for very near future upgrades by also adding 4 BNC connected probes, as many as 20 actuated valves and possibly another 8 channel relay module. This project is also connected to my Android phone via Blynk and already transmits RTC and DHT22 readings. I've also been able to toggle any of my relays over the web which leads me to believe I can also control any of the sensors and devices from abroad which IMO, will make gardening damn near brainless, but if nothing else, damn near effortless. It was the desire to automate my garden that brought me to Arduino and I hope to have this project in its entirety fully up and online in 6 months.

All that said, I hope to keep the volume of wires that stem from the outlets box as minimal as possible as I know there will still be many, but simply for aesthetics sake, it would be nice to have one cable/ribbon easily connect to each box to link them together, another cable/ribbon to connect all the valve controls in and the 4 BNC connectors will terminate on the side of the outlets box.

I don't know if the motors are brushed or not, but I think they are based on the cost of each 4 head unit compared with the going rate of a single dosing head. The mast unit cost me $80 ($20 per head). An adaFruit pump is $25, fleabay roughly$15, but I presume for the price, they all use brushed.

The pics (take 3)

both boxes motor bottom top of motor