On 01/24/2013 11:22 AM, Phil White wrote: > Hi All, > > I have 30 temperature sensors sitting in front of me at the moment. > They all report different readings when queried - which I would like > to fix on a reasonably permenant basis. > > Can someone advise how I go about calibrating them? There is, as far > as I remember, a register I can save into, and I have seen calibrated > sensors for sale (but can't afford this option) - yet I have no idea > on the procedure to DIY. > > Many thanks, > > Phil > > ------------------------------------------------------------------------------ > Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS, > MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current > with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft > MVPs and experts. ON SALE this month only -- learn more at: > http://p.sf.net/sfu/learnnow-d2d > _______________________________________________ > Owfs-developers mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/owfs-developers
Here is my somewhat scientific calibration method. I think it buys you something within 10C of the calibration temp, but there is a fair amount of noise in the readings. required equipment: precision temperature meter (RTD class A is ideal) glass beaker stirrer plate plastic gloves process: stick the 18b20s in the fingers of the gloves stick the glove and the meter probe in the stirred beaker (make sure the air escapes and there is good contact between the sensor and plastic) wait a few minutes for everything to stabilize read the meter and all the 18b20s 2-3 times, average the results load the offsets into your temp reading software Without a precision reference, I doubt it is worth too much. YMMV, jerry ------------------------------------------------------------------------------ Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS, MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft MVPs and experts. ON SALE this month only -- learn more at: http://p.sf.net/sfu/learnnow-d2d _______________________________________________ Owfs-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/owfs-developers
