Set up a circuit for reading water temp with a couple LM35s. Seemed like a really simple undertaking. Everything worked as expected on the bench. So we coated the LM35s in liquid electrical tape, let 'em dry and plunked em in the water tank. They went bonkers.
Well, maybe the liquid electrical tape wasn't cutting it? We made up a new set coated in either epoxy or polyester resin. Can recall. Same thing, works great on the bench, goes wild in water. So we finally potted the sensors in Sharpe caps poured full of polyester resin. There's no way water can get in there. Same thing! We even made up a set using different wire 'cause we thought the insulation may be seeping. Nothing has worked.
Has anyone seen anything like this?