The alarm check valves are not an issue for installing a vane type flow switch. There is not enough of a water surge in the alarm checks to create a problem. The standard specifically prohibits the installation of a vane type flow switch on a dry pipe system.
Please contact me off of the forum if you need more detailed answers. Kind Regards, Tim Frankenberg, CFPS Tim Frankenberg, CFPS Fire/Security Product Manager Potter Electric Signal Company www.pottersignal.com 800-325-3936 >>> [EMAIL PROTECTED] 2/8/2007 5:39 pm >>> I have been told that when the flow switch is too close to an alarm valve the sudden flow can damage or tear off the vane. Just what I was told once, notta clue if it's a valid concern -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Roland Huggins Sent: Thursday, February 08, 2007 6:26 PM To: [email protected] Subject: Re: WATERFLOW SWITCHES I suspect their use of the term LAMINAR FLOW is being applied too casually. It actually occurs only at very low flows. In a 1 inch pipe its maximum is around 1 gpm. I assume the concern was excessive turbulence (whether real or probably just imagined since listed assemblies can be much closer). Roland On Feb 8, 2007, at 3:13 PM, Thom McMahon wrote: > I believe the distance was 5 pipe dia., this came originally from > those pesky Mech. engineers, and was to allow the turbulence from the > valve to subside, into a more laminar flow, which at the time was > considered necessary for the operation of vane water flow switches. > Since we want to measure any flow (as low as .7 gpm or less for some > MFG.'s) Turbulent flow actually is more likely to activate the vane > switch than laminar flow at those low flow rates, hence the very short > distance from the valves to the FS in the riser assemblies, and floor > control assemblies. > > I believe I have correctly re-stated the info given to me by the > Potter rep. at the last convention. > > Thom McMahon > Firetech, Inc. > 2560 Copper Ridge Dr > Steamboat Springs, CO 80488-2136 > Tel: 970-879-7952 > Fax: 970-879-7926 > ----- Original Message ----- From: "Roland Huggins" > <[EMAIL PROTECTED]> > To: <[email protected]> > Sent: Thursday, February 08, 2007 4:00 PM > Subject: Re: WATERFLOW SWITCHES > > >> once upon a midnight dreary, the listing required vane type water >> flow switches to be a minimum distance away from the main >> drain. Although, if the same switch was part of a listed >> shotgun riser assembly, it could be installed much closer to the >> main drain. I haven't looked lately. >> >> Truth can be stranger than fiction. >> >> Roland >> >> On Feb 8, 2007, at 11:38 AM, <[EMAIL PROTECTED]> >> <[EMAIL PROTECTED]> wrote: >> >>> FYI The distance from a fitting or valve is only a "should" not a >>> shall. There are no UL or NFPA requirements regarding distance. >>> There are a number of riser assemblies on the market that put the >>> switch closer than the stated 24" from a valve or drain. If the >>> switch works during the test after installation it's a good >>> installation. >>> >>> Mike Cabral >>> >>> ---- Steve Leyton <[EMAIL PROTECTED]> wrote: >>>> Look at the tech data sheet for the switch. For Potter Signal >>>> products in the installation guidelines ... >>>> >>>> Steve Leyton >>>> Protection Design & Consulting >>>> >>>> >>>> -----Original Message----- >>>> From: Loren Johnson [mailto:[EMAIL PROTECTED] >>>> Sent: Thursday, February 08, 2007 11:06 AM >>>> To: Sprinkler Forum >>>> Subject: WATERFLOW SWITCHES >>>> >>>> >>>> Forum: >>>> >>>> Can anyone direct me to where it indicates that a waterflow switch >>>> for a wet pipe system has to be so many inches away from the >>>> control valve or an elbow/tee? >>>> >>>> I seem to have seen this somewhere before, but now I am unable to >>>> locate it. I thought it was in a pre- vious edition of 13, but I'm >>>> not sure. >>>> >>>> Thank you. >>>> >>>> >>>> Loren Johnson - CFPS, CET >>>> Fire Protection System Consultant >>>> The Hitchcock Company >>>> Peoria, IL >>>> >>>> >>>> >>>> ___________________________________________________________________ >>>> __ _______________ >>>> Do you Yahoo!? >>>> Everyone is raving about the all-new Yahoo! Mail beta. >>>> http://new.mail.yahoo.com >>>> _______________________________________________ >>>> Sprinklerforum mailing list >>>> [email protected] >>>> http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum >>>> >>>> >>>> _______________________________________________ >>>> Sprinklerforum mailing list >>>> [email protected] >>>> http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum >>> _______________________________________________ >>> Sprinklerforum mailing list >>> [email protected] >>> http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum >>> >> >> _______________________________________________ >> Sprinklerforum mailing list >> [email protected] >> http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum >> > > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum
