Calibrating a digital hydrometer, How do you do that??.

[Zed3]

So is the maximum length of time left in the bag important? Is 8 hours the minimun time? Is there a maximum time? What if you left it in for 12 hours.

Thanks

Zed

 

[Intheswamp]

Quote:
I think overnight (8 hours?) works ok. You could do a very simple experiement by recording the reading at 8 hours and then the reading in 12 hours (or 16 hours, or...).

Compare the readings....and report back to us what you find.

Ed

 

[Zed3]

OK, So my first attempt was with Kosher Salt. ( I could not find the Mortons) After 8 hrs the humidity was at 55% and after 22 hrs it was still at 55%. Second test with Mortons Salt started and after 15 minutes hunidity was at 60% and still climbing.

 

[Intheswamp]

Quote:
Well, that is interesting, but would be more meaningful if the same salt was used in both tests. After reading your report I went off reading about "salt". Seems that both salts are NaCl but there are apparently differences. Having said that, though, I'm not so sure how important it is to specifically use the canning/pickling salt. Of the types of salts the canning/pickling salt is supposed to be the quickest dissolving and have basically no additives (iodide, anti-caking, etc.,.). Kosher has been stated as having an anti-caking agent (but still is certified as kosher) and regular table salt has iodide, anti-caking agenst, dextrose, and ??? in it. Sea salts...all kinds of stuff.

There is also an issue of grain size (a teaspoon of big grain salt won't be as salty as a teaspoon of small grain salt...larger airspaces between the grains in the big grain teaspoon) and the ability of the salt to dissolve.

I'm no expert on salt (nor or calibrating hygrometers

) but stumbled upon this chef thread, "Table salt (vs) sea salt (vs) kosher salt" where they were talking about salt in a pretty detailed conversation.

Here is a link to an article I pasted this past January into a thread regarding the salt method of calibration: Calibrate Your Hygrometer - Two Methods This article is from a cigar website and humidity is very important in the storage of cigars (we're talking thousands of dollars worth of tobacco being stored in personal and business inventories). FWIW, the author states to use the easy dissolving canning/pickling salt, and specifically the Morton's brand.

It is interesting that your second test is apparently much different from your first. The question is it because of different substances/environment/whatever or because the hygrometer is flakey and giving inconsistent readings. ????
Isn't this fun!?

Ed

 

[Zed3]

The second test has stalled at 60%. It initially started increasing rappidly but stopped at 60%. It has been stuck on 60% for 41/2 hrs. So I pulled out my high dollar Hygrometer from Proimeter that I use in my home inspection business. I had not used it before because it has a probe with a cord and it was hard to get a good seal. I inserted the prob and taped the baggie closed. It went right to 70.7%. I will recheck it in a couple of hours. The Wal-Mart one is still 60%. Looks like it might be junk. I guess that is why we calibrate them. It is now 71.1% After 8 or so hours I will go back and try the Kosher Salt just for kicks.

Zed