Francois: I have been exposed to the weight charts only. I am surely interested in knowing about the moisture diffusion models. It sounds interesting. Regards, Ramon > -----Original Message----- > From: Francois Monette [SMTP:[log in to unmask]] > Sent: Tuesday, August 26, 2003 9:23 AM > To: [log in to unmask] > Subject: Re: [TN] Dry Cabinet > > Bonjour Yannick, > > Here are a few additional considerations relative to dry storage : > > Make sure that you understand exactly what kind of benefit you will get > from > your dry storage solution. In the contract manufacturing business, many of > your customers will expect that you comply with the guidelines from the > latest IPC/JEDEC standard J-STD-033A. This document contains precise rules > on how to account for dry storage. In summary the clock of exposure time > does not necessarily stop when previously exposed components are returned > to > dry storage, whether it be a dry cabinet, Nitrogen box or re-sealed dry > bag > with desiccant. The actual effect of dry storage on the remanining floor > life will vary based on the type of component (MS level), the type of dry > storage (RH level) and the complete history of exposure and subsequent > storage. > > I also suggest that you be careful when reading the marketing data > provided > by some of the vendors of dry storage solutions. In many cases their > conclusions are based on experimental data using a weight gain measurement > technique. This is not consistent with the current industry standard which > is based on a much more accurate moisture diffusion model. I can provide > more details and technical references if you are interested. > > Regards, > > Francois Monette > Cogiscan Inc. > Tel : 450-534-2644 > > > > > -----Message d'origine----- > De : Steve Gregory [mailto:[log in to unmask]] > Envoy=E9 : Thursday, August 21, 2003 11:19 AM > =C0 : [log in to unmask] > Objet : Re: [TN] Dry Cabinet > > > Hi Yannick! > > We use the McDry cabinents here, and they work great. The humidity = > level is > kept around 4% RH, and that's not too bad..you know, it never gets hot = > or > humid here in Tulsa, Oklahoma (GRIN). Also, when I start running low on = > beef > jerky, I'll just throw a few slabs of beef in for a few days...(JUST > KIDDING) > > You may think at first they are expensive, but when you figure the = > costs of > plumbing nitrogen, and the on-going expense of using the nitrogen, the = > costs > really aren't that bad. > > There's virtually no maintenance on them, as they self-regenerate the > dessicant in them. You should send the humidity meter out annually for > calibration, McDry will do that for you. In fact, they send you a = > notice > when yours is due for calibration. > > Camera dry boxes are kind of small, and the ones I've seen don't go = > down to > the low humidity levels that the dry boxes for electronics do. > > One good thing about desiccant cabinents, is that you can avoid baking = > if > the components are left in the dry box long enough. According to the = > data, > they will actually "de-humidify" the components bringing the absorbed > moisture down to a level below where "pop-corning" or micro-cracking = > can > occur. > > There's two companies that I know of that make these desiccant dry = > boxes. > One is McDry (the ones I use), and the other is a company called Toyo > Living. This last APEX show is the first time I've seen Toyo Living dry > boxes. They supposedly are cheaper than McDry, and also contain heaters = > that > work in conjunction with the desiccant. Here's the links to both = > companies" > > http://www.seikausa.com/mcdry/ > http://www.toyoliving.biz/ > > Best regards, > > -Steve Gregory- > > > > > Hi,=20 > > we'll use the cabinet for keep our QFP dry, we use to have a moisture > probleme right now, I don't know the level of humidity/dryness to be > maintained, cause it's maybe depending of the component, we don't what > something complex, jsut a standard cAbinet not to expensive... > > Yannick > > --------------------------------------------------- > Technet Mail List provided as a free service by IPC using LISTSERV 1.8e > To unsubscribe, send a message to [log in to unmask] with following text in > the BODY (NOT the subject field): SIGNOFF Technet > To temporarily halt or (re-start) delivery of Technet send e-mail to > [log in to unmask]: SET Technet NOMAIL or (MAIL) > To receive ONE mailing per day of all the posts: send e-mail to > [log in to unmask]: SET Technet Digest > Search the archives of previous posts at: http://listserv.ipc.org/archives > Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 > for additional information, or contact Keach Sasamori at [log in to unmask] or > 847-509-9700 ext.5315 > ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------