I've heard Ed's story many times and don't know how hos particular DI worked but although charged air in the system is a common DI arrangement it's not the only way. An electric detection system plus a pneumatic pilot line would qualify as DI. DI just requires two distinct events to release water.
On Thu, Jun 14, 2012 at 8:11 PM, Ed Kramer <[email protected]> wrote: > A double-interlock preaction with open sprinks? How did the air pressure > part of that work? > > Ed Kramer > Manhattan, KS > > > A story I have repeated often. Sometime after Adam was kicked out of > > Eden KQED TV in San Francisco had an event. Fairly new preaction > > system. > > Normally energized solenoid to trip double interlocked system. Battery > > backup for the system. Power failure lasting some time. Person on duty > > hears water running under raised floor. Call water department. They > > say call fire department. 28 sprinklers are flowing on the stage and in > > the auditorium. PA valve in locked room. No key on premises. FD won't > > break down door, as there is no fire. Building engineer arrives two > > hours into the event and turns off water. > > > > Ed responds to find all this mess, and oddly enough 28 open sprinks and > > one intact. Finds out later that the sprinkler foreman on this job had > > just done a deluge system at the airport. Same equipment, same > > manufacturer. At the end of installation he had the apprentice knock > > out all the links. Of course he missed one. Total exposure carpet, > > plush seats, close to > > $900,000 in color cameras and the like. Total damage $20,000. Of > > course those were 1970's dollars, but so were the $900,000 > > > > > > Ed Vining > > 4819 John Muir Rd > > Martinez CA 94553 > > 925-228-8792 > > Cell 925-787-0465 > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > -- Ron Greenman Instructor Fire Protection Engineering Technology Bates Technical College 1101 So. Yakima Ave. Tacoma, WA 98405 [email protected] http://www.bates.ctc.edu/fireprotection/ 253.680.7346 253.576.9700 (cell) Member: ASEE, SFPE, ASCET, NFPA, AFSA, NFSA, AFAA, NIBS, WSAFM, WFC, WFSC They are happy men whose natures sort with their vocations. -Francis Bacon, essayist, philosopher, and statesman (1561-1626) -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://fireball.firesprinkler.org/mailman/private/sprinklerforum/attachments/20120614/a0b9715c/attachment.html> _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum
