Video 12 – Leapfrogging Problems with Reusable Probes
The other issue, of course, is using reusable probes where we move them or leapfrog from one hole to another. Let’s take a look at that in the next slide.
This next slide shows a couple of holes drilled into a concrete floor slab. We’re going to place a couple of sleeves and plugs into those holes and let them sit. You can see from the cutaway cross-section here that there is a large volume of air that has to equilibrate by moisture moving up and out of the bottom of the hole into the sleeve.
When we’re ready to make a measurement with a reusable sleeve, you have to pull out the plug. Put the probe in and that probe then displaces that air. You’re bringing in air inside of the probe from the room. So now it has to re-equilibrate. With reusable probes, then it has to sit, and as I mentioned, anywhere from perhaps an hour to several hours to re-equilibrate completely.
Then you pick that probe up and out. Move it over into the next hole, as you see in the animation here, and it has to re-equilibrate again in that hole.