Question 1

What's the difference between Cobalt and Cobalt 14?

Accepted Answer

"Cobalt" is our original line of connectors, where the bulkhead shell fits in a 10-mm hole.  Some of our customers call it "Cobalt 10," but we still just call it "Cobalt" because it was the original size.  "Cobalt 14" is the larger size of connectors, with the bulkhead fitting in a 14-mm hole.

Question 2

What makes Cobalt and Cobalt 14 connectors different from other underwater connectors?

Accepted Answer

No potting or overmolding:  Most other subsea connectors use potting or overmolding to make the waterproof seal between the connector shell and the electrical contacts. In Cobalt and Cobalt 14 connectors, however, the pins/sockets are press-fit into a PEEK plastic connector core which is then press-fit into the connector shell. No potting or overmolding is required.
Immediate availability: We ship the vast majority of our orders within 2-3 days. Custom items or large orders may take a week or two, but we are striving to cut the lead time as much as possible.
Low cost:  Because of their unique design, the manufacturing of Cobalt and Cobalt 14 connectors is relatively quick and does not require special equipment or tightly-controlled potting/overmolding processes, thus reducing cost.
Small size:  Cobalt and Cobalt 14 connectors are significantly smaller than other subsea connectors, both in diameter and length.  This makes it easy to integrate them into smaller marine robotics projects. The Cobalt bulkhead connectors also have M10 threaded shanks instead of 7/16-20 threaded shanks, making them compatible with Blue Robotics products.  Cobalt 14 bulkheads have M14 threaded shanks.
The one limitation of Cobalt and Cobalt 14 connectors is that they are not wet-mateable. If you absolutely need to connect and disconnect your connectors underwater, you'll have to use a SubConn-style connector.

Question 3

What makes Cobalt cables different from other underwater cables?

Accepted Answer

No potting or overmolding:  Cobalt cables utilize a robust mechanical seal between the cable jacket and the connector shell. The cable jacket consists of high-quality polyurethane tubing with a smooth inner wall, which fits over a barbed shank on the connector shell. This makes Cobalt cables more simple and more reliable than potted/molded cables. In some cases, customers may want to put a Cobalt connector on their own cable. For these situations we offer a cable termination kit that does require a simple potting operation, but even then the potting can be done by an amateur without the need for a mold or any special equipment.
Immediate availability: We ship the vast majority of our orders within 2-3 days. Custom items or large orders may take a week or two, but we are striving to cut the lead time as much as possible.
Low cost:  Because of their unique design, the manufacturing of Cobalt cables is relatively quick and does not require special equipment or tightly-controlled potting/overmolding processes, thus reducing cost.

Question 4

Why do Cobalt cables have a maximum length of 2 meters?

Accepted Answer

Our cables are made of polyurethane tubing with wires inserted into the tubing. The polyurethane tubing makes it possible for us to install connectors onto the cables without potting or overmolding.  However, it does mean that there is a limit to how long we can make the cables (you can only push wires into the tubing so far).  If necessary, we can sometimes make a cable a little longer (like maybe 3 meters), but it might cost a bit more.

Question 5

Why do double-ended Cobalt cables have a minimum length of 0.6 meters?

Accepted Answer

For double-ended cables, there is also a lower limit on the cable length due to the manufacturing process. If you really need a longer or shorter cable, give us a call. We know some tricks.

Question 6

What is a Cable Termination Kit?

Accepted Answer

A cable termination kit allows you to put a Cobalt or Cobalt 14 connector onto a cable of any length, and it works with a wide variety of underwater cables available from other manufacturers.  Unlike our standard Cobalt cables, the cable termination kit doesn't require special polyurethane tubing as the cable jacket, and it doesn't use a mechanical seal between the cable jacket and the connector shell. Instead, it uses potting material (typically epoxy) to seal the cable jacket to the connector shell.
So the advantage of a Cable Termination Kit is that it gives you more options in both cable length and cable type, but the disadvantage is that it requires a potting operation.

Question 7

Do you sell pre-made cables made using the Cable Termination Kits?

Accepted Answer

Only as custom items.  Please contact us if you have a special need.  Because the cable termination kits require potting, they are more labor-intensive and thus more expensive.

Question 8

What torque do you recommend for Cobalt and Cobalt 14 bulkheads?

Accepted Answer

As a starting point, we recommend 10 Nm for the Cobalt (M10) bulkheads.  However, that is just an estimate and it depends on many factors, like the material of the housing, whether you're going to use Loctite, etc.  For the Cobalt 14 (M14) bulkheads, we recommend 30 Nm as a starting point.  Again, it depends on the application and we recommend testing.

Question 9

How much current can your connectors handle?

Accepted Answer

We base the current rating of our connectors on the manufacturer's rating for the electrical contacts (pins and sockets) used in the connectors. The current ratings listed on our datasheets represent the current that the connector or cable can handle continuously. However, as with many other electrical devices, our connectors and cables can handle significantly more current as long as that current is only momentary. How much momentary current they can handle depends on how quickly heat will build up inside the connector or cable, and is difficult to predict. If you want to exceed the specified current limit, you do so at your own risk.

Question 10

Can your connectors be used for 400-volt systems?

Accepted Answer

You can find "hi-pot" (high-potential, or high-voltage) test results for our connectors on the Resources tab of our website. Exercise extreme caution when using any voltage above 30 volts, especially near water, as these connectors have metal shells and semi-exposed contacts.

Question 11

What is the depth rating of the Cobalt cables?

Accepted Answer

Our Cobalt cables, just like the connectors, are rated to 600 meters. However, you might see the cable jacket squish a little if you take them to this depth since there is some air space inside the cables.  This should not affect the performance of the cable.

Question 12

Do the connectors have an open-face depth rating?

Accepted Answer

No. All of our connectors are designed to be waterproof up to 600 meters in the open-face (unmated) condition, but due to manufacturing tolerances we do not guarantee an open-face depth rating.  However, in the closed-face (mated) condition, all of our connectors are rated to 600 meters.

Question 13

What is the depth rating of the Simple Penetrators?

Accepted Answer

The Simple Penetrators themselves are rated to 600 meters. But the tubing/cable jacket that is attached to the Simple Penetrator may squish at depth. Best practice is to make sure that the wires fill the inside volume of the tubing/cable jacket as much as possible to keep the tubing/cable jacket from squishing.

Question 14

Why do you have female sockets on the cable connectors and male pins on the bulkhead connectors?

Accepted Answer

The female sockets tend to be longer and larger in diameter than the male pins, and thus do not fit inside the bulkhead connector due to the limited space inside the threaded portion of the connector.

Question 15

What is the potting I see inside the threaded portion of the bulkhead connectors?

Accepted Answer

This is epoxy. It is put there to provide strain relief to the wires and to prevent small bits of metal from getting inside and causing a short. It is NOT required to make the connectors waterproof.

Question 16

Any other tips?

Accepted Answer

Make sure to lubricate the connectors, including O-rings, before using them. They may go together easily without lubricant, but will almost certainly be difficult to separate later.

Frequently Asked Questions