On Sat, January 13, 2007 13:48, Peter Kropf said: > George - > > This is great. Thanks for posting it!
That'll work for a Rate of Rise detector. The ones you see in office/commercial buildings are usually 20F rise/min before they trip the fire alarm. In south facing glass offices, they may install 35F RoR detectors, but no more than that. Peter, were the sprinklers set off by thernal/melt trip sprinkler heads, or rate of rise detectors? The RoR ones look like little white flying saucers with an extra little disk hanging off the bottom center. A simple fan would keep them from tripping. Just keep the surrounding air mixing to temper the... well, temperature. Tim > > On 1/13/07, George M. Zouganelis <[EMAIL PROTECTED]> wrote: >> As of how fast such a sensor can react, I tested today a DS18B20 >> dropping into a cup >> of just boiled water. Temperature got from room temp. to stable 90C in >> 10 seconds: >> : >> 23 16:19:40 >> 23 16:19:42 >> 23 16:19:43 >> 47 16:19:46 >> 69 16:19:47 >> 80 16:19:48 >> 83 16:19:50 >> 86 16:19:51 >> 88 16:19:52 >> 89 16:19:53 >> 90 16:19:55 >> 90 16:19:56 >> 90 16:19:57 >> : >> DS28B20's head was half covered with a heat shrinkable tube, to protect >> it's pins. >> I have attached an .xls with logged data and graphs >> >> >> I have used them in a laboratory a/c monitoring and i have experienced >> ripples when a/c starts >> 'correcting' room temperature. >> >> at http://ikaros.dmst.aueb.gr/logs/labs.html, you can see for ELOI2 the >> ripples (click the 'last24h' image) >> >> A/C is at the ceiling (about 4m high), sensor is near the wall, >> behind an office, under the A/C, half a meter above flour. >> >> In the same room, there is a rack, and i have placed a sensor at it's >> internal side, placed near the top server. >> Notice again the ripples at http://ikaros.dmst.aueb.gr/logs/racks.html. >> >> ELOI3's rack is in a 4mx3m room. >> >> >> >> >> >> I was thinking of trying to use some DS18S20 sensors to monitor the >> >> temperature above the various fire effects. The sensors would be >> >> mounted to the ceiling above the various fire sources. The DS18S20 >> >> looks to have a range that'll support our needs, -55°C to +125°C. >> >> Since the sprinklers trigger at around +82°C that should work fine. >> >> But I'm concerned about being able to monitor temperature changes >> fast >> >> enough to provide accurate monitoring. The two aspects of that are >> how >> >> fast / often can I realistically expect to read the temperatures on >> a >> >> string of 5 to 7 sensors and how fast do the sensors themselves >> react >> >> to changes in temperature. >> >> >> Peter Kropf wrote on 13/1/2007 20:17: >> > I'm hoping to use the DS18S20's since I've got a bunch of them here in >> > my studio. I'll need to play around with them this morning to see how >> > they react to temperature changes... >> > >> > - Peter >> > >> >> >> >> ------------------------------------------------------------------------- >> Take Surveys. Earn Cash. Influence the Future of IT >> Join SourceForge.net's Techsay panel and you'll get the chance to share >> your >> opinions on IT & business topics through brief surveys - and earn cash >> http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV >> >> _______________________________________________ >> Owfs-developers mailing list >> Owfs-developers@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/owfs-developers >> >> >> >> > > ------------------------------------------------------------------------- > Take Surveys. Earn Cash. Influence the Future of IT > Join SourceForge.net's Techsay panel and you'll get the chance to share > your > opinions on IT & business topics through brief surveys - and earn cash > http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV > _______________________________________________ > Owfs-developers mailing list > Owfs-developers@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/owfs-developers > -- Tim Sailer Coastal Internet, Inc. www.buoy.com 631-399-2910 ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys - and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers
