Can tape over the probe cause erroneous readings? - Printable Version
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RE: Can tape over the probe cause erroneous readings? - CC Solutions - 07-03-2012 01:20 PM
(07-03-2012 12:44 PM)rthompson Wrote: No, It doesn't matter if you put tape over the hole or not
I agree the initial reading is not affected by tape, but what about putting a vapor retarding duct tape over the probe for four months as you track RH? And you know some guys put a nice big area of tape down, 3 strips wide and 3 strips across, so basically a 6" square of vapor retarder over the probe.
RE: Can tape over the probe cause erroneous readings? - rthompson - 07-03-2012 02:02 PM
I meant a strip of tape not a covering of tape. Tape, in a covering, will cause the concrete to dry differently.
RE: Can tape over the probe cause erroneous readings? - CC Solutions - 07-03-2012 02:17 PM
That is my point.
When some conduct long term testing, the probes are covered with a LOT of tape to keep out water, dust and prying eyes. So we get these questions asking why the probes are hanging for months with little change and why do new probes read significantly less than the old probes in the concrete.
Hysteresis explains some of the phenomenon, but I think we need to get some advice in the installation instructions advising against covering the sensors with tape, plastic, cardboard etc. It just throws off our readings.
RE: Can tape over the probe cause erroneous readings? - eaadams - 07-09-2012 01:27 PM
What is the difference between a covering and a strip?
I usually see an "X" over a probe with 2" tape.
RE: Can tape over the probe cause erroneous readings? - CCR - 07-10-2012 10:47 AM
I always place a couple of strips of lightweight bright colored tape over the sensor caps and write "DO NOT DOSTURB" on the tape. This seems to work to keep the trades respectful of the testing process (until today). My return trip after 72 hours revealed a couple of locations where someone removed the tape, wadded it up and left it next to the open sensor. Very professional behavior, eh?
RE: Can tape over the probe cause erroneous readings? - CC Solutions - 07-12-2012 06:06 AM
There have been times when I wondered if others may have dribbled some water in the hole.... Just to mess with us.
RE: Can tape over the probe cause erroneous readings? - CCR - 07-12-2012 07:41 AM
or throw in a little dirt or half a turkey sandwich
RE: Can tape over the probe cause erroneous readings? - eaadams - 07-12-2012 12:50 PM
I have a 2nd tester now using a puddy like caulking between the cap and sleve / concrete. Fails often but doesn't prevent surface moisture from coming out.
Is there such a thing as a duct type tape that breaths? like a mesh tape? I'd be more comfortable with that.
In reality I picture a new wagner product. It would be a cylinder (battery shaped) made to fit in the meter hole. It would fill the hole and prevent debris from entering and then I would also have a metal core running the full length so I could remove it with a [edit: magnet]. If you wanted to get fancy you could integrate a mushroom cap shape to it to protect the edges.