I did a couple of preaction systems about 3 years ago. The FDT and field tests were within 1-2 secs if I recall correctly. I was pretty impressed. We did have a fire pump and tank on the project, so there would not have been any variability from a city supply.
The systems were large (+/-1200 gallon capacity) and that is why we did the FDT to make sure it worked before installation. We did have the Tyco DV-5 preaction valve and the QRS accelerator on the system. The FDT would not work with our looped system. We had to make it a tree for the FDT to work. Tyco says it works on simple loops, which is what we had, but it would not work. We sent the file to tech support. Their response was: Well, I guess it won't work on a loop like that either. So, a minor bump in pipe size and all went well. FYI - The fire pump on the system was a 150 psi @ 1500 gpm diesel pump. Travis Mack > Anyone done some field testing out of curiosity on real systems you've > installed and compared the results of FDT vs. real world. > > I did once about 6 years ago and FDT and real world were 45 sec. vs. 70 > sec. > respectively. Raised questions but with a test of one no conclusions. > Haven't been involved with FDT since by coincidence. > > Chris Cahill, P.E. > Fire Protection Engineer > Sentry Fire Protection, Inc. > > 763-658-4483 > 763-658-4921 fax > > Email: [email protected] > > Mail: P.O. Box 69 > Waverly, MN 55390 > > Location: 4439 Hwy 12 SW > Waverly, MN 55390 > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of George > Church > Sent: Wednesday, June 17, 2009 1:12 PM > To: [email protected] > Subject: RE: Slow responding dry pipe valves > > 2. Look into obtaining FDT calculation software to either prove your > systems' ability to meet the water delivery requirements, or what you can > save, or what you can change to make them work. > > _______________________________________________ > Sprinklerforum mailing list > http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > For Technical Assistance, send an email to: [email protected] > > To Unsubscribe, send an email to:[email protected] > (Put the word unsubscribe in the subject field) > -- _______________________________________________ Sprinklerforum mailing list http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
