Waterproof Connections

How do you make waterproof connections to an outdoor project? My project is a controller for a homemade pool heater. I need to connect power and two DS18B20 sensors to the project box. I found these aviation connectors on Amazon. Has anyone used these or something similar? Is there something better that someone would recommend?
Edit: I should have mentioned that I want the connections to be removable.

I make water - resistant connections for outdoor enclosures and have never had an issue with these:

Note, these are not intended for solutions where your enclosure would be submerged - that is a much higher bar.

Using a cable gland, you pass your cable through and make your connections. Then you tighten the “nut” which cinches a rubber gasket tight around the cable. I have used this PG-7 (the number 7 is the size) with the DS18B20 sensors.

Hope this helps,



I’ve used those before… I think they work fine. For the DS18B20 and even power you could consider just using a chord grip rather than a connector. That’s what I did for an external DS18B20:

I use chord grips from Polycase, where I get the enclosures from. CG3 Cable Glands | Strain Relief & Cord Grips for Enclosures

For power, I mostly use Switchcraft as it was a bit sturdier or seemed more rugged than the Amazon link you shared. A little more $$ though. That said, if the cable was always there and always plugged in, I’d just use another chord grip for that as well.

For my application, I wanted something removable since many times the enclosure may not be in a place with power. Having a plug also gives me the options for USB cable with usb battery pack/wall charger, solar panel or cable with alligator clips for 12 VDC. I’ve been very happy with switchcraft. https://www.digikey.com/en/product-highlight/s/switchcraft/sealed-power-plugs-jacks You can also buy just a cable with flying leads. Would be nice if they had a pre made cable with a USB connector on it as I just made up a bunch of them the last few weeks. I buy a USB cable with flying leads and then solder it to a Switchcraft connector.


Thanks, @chipmc and @jgskarda.