Divers often have to wear a special warm underwear and a drysuit to feel comfortable in the winter in cold water. But even in the thickest and most expensive thermal insulator you can freeze during a long dive. Moreover thick clothes restrict movement. The best way would be to use electric heating clothing, but it is expensive and for its connection it is required to equip a drysuit with a special valve and connector. Let's save some money and make it ourselves. We made this design 5 years ago and it still works great!
Step 1: Items
1. We bought this connector and upgraded it to IP69 - $3,4 for male + 1 female
(instead of diving E/O connector for 69 Euro!)
2. Orings 1.6mm ID - $4
put one ring on each contact
3. A few pieces of round acrilyc plastic $6
we just glued them together then drilled a hole to insert the upgraded male connector (a factory made adapter costs $130)
Step 2: How To
Glue together a few acrylic discs. Should get a housing height of 40mm and a diameter of 50mm. Then drill a hole 20,5mm in the side for the connector, drill a cable hole centrally on one side and three screw holes. Solder a flexible wires to the connector and glue the connector to the housing. Install the housing on a dry suit, as shown in the photos. For sealing we used Aquasure glue.
The connector we used is marked IP68. We made a series of experiments in a hydraulic pressure chamber and found that the IP index can be easily increased to 69 if we set the orings on the connector pins. The connector with additional orings can be freely disconnected and connected even in seawater, the current leakage does not exceed 0.01 mА (very low level). In this way we were able to feed the heating system inside the suit with a standard battery canister from a diving torch. This ensures safety and allows to control the heating temperature.
Step 3: Safe and Warm
I use a homemade battery canister for a diver's flashlight. The canister is equipped with a 12V 20Ah battery. On the canister is installed the same connector as on a dry suit so I can switch directly under the water powerful light or heating. The switch on the canister has 3 power modes and right under the water I can adjust the heating power.
During diving I use gloves with DIY carbon tape heaters 2х10 watts and a DIY carbon heated vest 36 watts. In our lakes the water temperature at a depth of more than 10 meters is about 32 degrees Fahrenheit, but thanks to heated clothes made of carbon tape I can swim for 1-2 hours and do not cold at all.