Can electrical Sensors be successfully
waterproofed? If so, what products are
recommended?
Use a layer of dielectric grease around their connectors (but not the actual pins themselves) and that will help keep out moisture. You may have noticed that grease packed around light bulbs in tail lights and marker lights.
Which sensors?
What problem are you trying to solve?
Sensors not subjected to heat can be waterproofed with 100% silicone RTV. But not the business end. But I can’t think of a single sensor that would need this.
Perhaps if you clarified exactly what it is you’re trying to do, we could offer a more targeted solution. The prior suggestions were good so I’m offering another option:
Here’s an awesome product I have used for years to waterproof RC boat servos. You just dunk the entire servo board into this solution and viola! they work under/in water. It isn’t cheap but it is effective and a little goes a long, long way. Check it out here- http://www.aerotrend.com/shop_cat.php?cat=1