Electronic – What electrical connectors to use underwater

autonomousconnectorunderwater

I am looking at doing a project with a AUV (autonomous underwater vehicle) and need to know the best type of connectors to use. I have listed the things I need from most important to least important:

  1. Reliability
  2. Ease of in installation
  3. Availability(ship time)

Project Details

My project is to have a main board(small atom motherboard), and a few other small micro-controller boards(arduinos) to be inside a main compartment. This compartment will utilize the connectors to provide a leak-free interface with the AUV's navigation(thrusters, ballast) and sensor systems(sonar, depth gauge).

The vehicle will only be subject to about 20 – 40 feet dept, or around 18 psi. I need something that can be connected "dry", and then is waterproof afterwards, rated IP-68. I have looked a little into Buccaneer. Does anyone have any experience on what is the best, or if I can DIY these?

Picture of Buccaneer Connector

Buccaneer connectors

Best Answer

SeaCon is the company we use at work, but at hundreds of dollars per connector in most cases, are probably way out of your league.

That SubConn connector is a lot more than you need as well. It's designed for underwater mating, which I doubt you'll do. You're probably planning on connecting everything up in air and then dunking it in water. Underwater mating connectors also have ridiculously high mating/unmating forces and are rather large.

Given that your max depth is 20 feet, and pressure is about 1/2 PSI per foot, you're looking at 10 PSI. So any connector that can maintain a hard vacuum (14.5 PSI or so) would be feasible.

There's not a huge market for these things (most UUV projects are research or oil exploration related, can afford Seacons or equivalent, run to thousands of PSI of pressure, use pressure-compensated or water-blocked cables, and buy a lot more than you), so most of the products you can afford and that might work will not say anything about pressure resistance.

I'd recommend starting with "harsh environment" connectors. They are usually variants of standard connectors like USB or Ethernet, and have an extra outer shell, screw lock, and an O-ring seal. Be careful with O-rings. It's real easy to pinch one and ruin it if you treat it like a normal connector, and sometimes they need a lubricant/sealant to work well.

You should probably rig up a leak detecting circuit, get a harsh environment connector, put it in 20 ft. of water, and see if it's up to snuff.

Related Topic