So what drove the change from the old way of working trip times (under 500 gal. all was good, 500-750 gals. and either 60 seconds or QOD, over 750 gals. QOD and all is good)? was it due to systems failing due to too long trip times or was it a way to sell an expensive computer program? If due to failures did it happen in a cross section of buildings or in certain types of buildings and if the latter is it necessary to treat all systems equally? Certainly requirements to trip test everything to 60 seconds in years past was based on local requirements arrived at collectively by AHJs because they wanted it and it was complied with enough to become the usual thing to do until it became codified--first locally and then in 13. Where's the data that supported this costly change at point in this migration from what 13 said to what it says now? Enquiring minds want to know.
On Wed, Jun 17, 2009 at 1:08 PM, George Church<[email protected]> wrote: > To address Mike's concern about trip time, the QRS switch is pretty > dependable- it samples the air pressure every .1 seconds and after enough > degradation is detected 3x in a row, it trips. We input 3.5 second trip time > even tho it would be a little less since it takes less than a .5 second to > trip it, but :) maybe on one we'll need to make it 3.1 seconds so we gain .4 > seconds in FDT. There have been days, eh Ken, when .4 seconds is the dif > between making it or not making it. > > I'd not rely on the sampling rate in my memory and look at Tyco's electronic > acelerator data page, or Potter's QRS sheet. The 3.5 seconds is right. > > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Ken Holsopple > (forum) > Sent: Wednesday, June 17, 2009 4:00 PM > To: [email protected] > Subject: RE: Slow responding dry pipe valves-FDT > > > Chris wrote: > >>Let me clarify, I thought it was way too far off in the 1 example I was >>involved with. 45 sec. calc after it repeatedly failed in the real world > at >>any place between 70 sec and 80 seconds. The contractor used it after the >>fact when they failed the 60 second test on at least 3 occasions. Tyco did >>the calc's not the contractor, I checked the input. This was not long >>after >>it was released. > > > > > My mistake Chris....sorry to put words in your mouth. Was not my intent. > > Even since we have been using the software there have been several factors > identified by Tyco that would cause delay in the real world. Such as delay > in the start-up of fire pumps and large underground loops causing delay > because of inertia. > > Ken Holsopple > Designer > Rowe Sprinkler Systems, Inc. > > > > _______________________________________________ > 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) > -- Ron Greenman at home.... _______________________________________________ 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)
