Originally Posted by cavie
The only thing the Non contact tester will tell you is there is some sort of voltage present. It can tell you nothing about the ground or neutral or which wire the voltage is on. Be safe.
If your rig is hot, it will tell you so. It should be grounded. If the post is hot, it will tell you so. It should be grounded. Then a meter can tell you the exact voltage. Why should a grounded post or RV be hot. Well a missing ground to the main power pole. It has killed people thinking that their rig was grounded. Just an open ground in a park section can do this. A kid died two years ago do to a faulty ground in a park section's power wiring. What you do not know can kill you. It doesn't happen very often, but it does happen.
I have a very sensitive non contact tester. I have used it to follow the wiring in the walls to know their exact routing. It is a quick and useful tool. Not and end all be all tool.