Connectors on ESC's

My ROV team competes in the Milwaukee MATE regional competition and we were wondering what kind of connectors you guys use on the ESC’s. Were looking for small wire connectors that are waterproof or can be waterproofed. Thanks -Soren

Hi Soren,

So far, we’ve primarily been using passthroughs or penetrators due to their low cost. We will have our own cable penetrators for the thruster cables available in our store soon. In the meantime, I’d recommend looking at high pressure cable gland like those available from SealCon:

Those are rated to 300 ft depth and are fairly inexpensive.


Sorry for the misunderstanding, we have our own passthroughs, I was more interested in the bullet connectors on the ESC itself, are those waterproof? We’ve developed our own connectors for the electronics housing, were looking for connectors that can be connected and disconnected on the exterior of the electronics housing. We have some ideas, just looking for a few more.


Ahh! Sorry I misunderstood. We haven’t done a whole lot with connectors outside of the watertight container. The bullet connectors on the ESC are not waterproof. They’re not exactly small, but I’d recommend looking at the SubConn connectors, which can be purchased through Amron Intl.

Some of the small ones are around $45 per set but that’s the least expensive.

Perhaps other users on here have more insight?


I have used the Crouse-Hinds underwater mateable cables and the Seacon variants before. You need to watch your current rating on the connectors. So if you are looking at three feed lines, you might have to go with a six pin connector or get one with the highest gauge wire that you can.

The “wet” mate connectors are nice. What you need to do with them is to fill up the female connector holes with Dow Corning #4 so when you mate it with the male version it will fill all of the voids with the silicone grease. The DC-4 is outstanding for use in seawater. We use it on submarine cables a lot with many years of submerged life.

Please understand that you would only use the DC-4 in cables that have “purge” holes in the rear of the female connectors. The Crouse-Hinds connectors are like that. Look at the hole half way back on the picture for this link.

The Seacon connectors are meant to be straight mate without grease. The Crouse-Hinds female receptacles are nice because you already have a bulkhead mount design with that unit. You would need to drill a hole in your container and use a nut to hole the receptacle securely in place. What you don’t see in the picture is an O-ring race on the back of the “nut” where you see the threaded region.


There’s a whole range of waterproof electrical connectors. IP68 is typically the highest immersion rating but that’s only rated for 1+ meter for 24 hours. I found several inexpensive IP68 connectors on Aliexpress, but they self-certify, so buyer beware. I’ve bought the brand in the link below and am happy with it, although my application isn’t at depth.