> Subject: Re: iButtons no longer water proof Is there some reason you are not using one of the water proof containers made specifically for iButtons? Are they too expensive?
From: www.embeddeddatasystems.com/ iButtons: "water proof if placed inside DS9107 iButton capsule " DS9107 iButton capsule: "The iButton Capsule is a mechanical enclosure designed to protect Temperature Logger iButtons (DS1921 and DS1922 series) from moisture, solvents and pressure." Mike FROM: ECOLOG-L Digest - 17 Jun 2010 to 18 Jun 2010 (#2010-165) > Date: Fri, 18 Jun 2010 14:26:15 -0700 > From: Sarah Gilman <[email protected]> > Subject: Re: iButtons no longer water proof > > The quality really has gone down in the past 5 years or so. > > I seal the seam between the two pieces of metal with aquarium silicone =20= > > and then wrap the whole ibutton in parafilm before deploying them. =20 > The whole thing is embedded in marine epoxy and deployed in the =20 > intertidal, where its submerged daily. I still have some failures, =20 > but nowhere near the 66% mentioned by a previous poster. It's most =20 > likely the seam between the metal parts that is most sensitive to =20 > submersion. > > You might also be interested in these: > > Modification and miniaturization of Thermochron iButtons for surgical =20= > > implantation into small animals > http://www.springerlink.com/content/d806346722741317/ > > Robert and Thompson, 2003 K.A. Robert and M.B. Thompson, =20 > Reconstructing Thermochron iButtons to reduce size and weight as a new =20= > > technique in the study of small animal thermal biology, Herpetol. Rev. =20= > > 34 (2003) (3), pp. 130=96132. > > Fernando P. Lima and David S. Wethey 2009. Robolimpets: measuring =20 > intertidal body temperatures using biomimetic loggers. Limnology & =20 > Oceanography: Methods > 7:347-353 > > > - Sarah > On Thu, Jun 17, 2010 at 9:32 PM, John Gerlach <[email protected]> wrote: > >> I've been using iButtons for 4 years to measure water temperature which >> allows me to determine ponding depth through time. The batch that I bought 4 >> years ago was essentially waterproof and their failure rate ran about 5% per >> year regardless if they were immersed or not. This seemed to mirror the >> experience of other users. I bought a new batch last December and just >> determined that 66% of the immersed the new iButtons failed. I haven't >> opened any of them up but I assume that the failures were caused by leakage. >> To me this indicates that the manufacturing process has changed. The >> supplier responded to my inquiry simply that they are not warranted to be >> water proof. All I can say is that the change means that we have lost a very >> useful tool. >> >> John Gerlach
