Todd, I'd suggest you install a pressure switch (high/low style) and use it as your main waterflow alarm like other tank systems do. Of course that doesn't help getting water to the head but at least you'd ring and roll the trucks. They're listed for this use. Tom
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Todd Williams Sent: Monday, November 02, 2009 11:54 AM To: [email protected] Subject: RE: pump failure/flow alarm Just had another conversation with the fitter. When the IT is opened, the paddle goes up for about 3 seconds and then settles back to neutral. My guess is that the majority of water is discharged in the first few seconds and the pressure pretty quickly dissipates to elevation head only and the flow would be only a trickle. At 50 psi, a 1/2" sprinkler would discharge 39.6 gpm initially, rapidly declining. How long would the 8 gpm need to be maintained for the flow switch to activate? The duration of the delay? The 39.6 gpm translates to 0.66 gallons per second. If that 50 psi remained steady, it would take 12 seconds to discharge 8 gallons, well under the 30 second setting on the FS. The minimum 8 gpm flow requires a 2 psi discharge out of a 1/2" orifice. Will the pressure at the orifice drop from 50 psi to 2 psi in 30 seconds in a closed system? Probably. Am I over thinking again? _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.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)
