Ellipse® Pitot Tube Meter
PFA Fire Pump System
2000
1500
1000
2500
3000
GPM
M
F
APPROVED
PFA-XXX
X inch
250 SWP
X/XX
S/N AXXXXXXX
3500
4000
M
F
APPROVED
FLOW M ETERS
DEBITM ETERS
MEDIDO R DE F LUJO
PTT-UM-00523-EN-02 (April 2014)
User Manual
Ellipse® Pitot Tube Meter, PFA Fire Pump System
CONTENTS
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Specications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Pipe Orientation and Sensor Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Installation Instructions, Single Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Installation Instructions, Double Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Gage Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Location Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Gage Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Gage Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Page ii April 2014
INTRODUCTION
The Preso Model PFA Fire Pump System is FM-approved and features the
Preso Ellipse primary flow sensor. The Preso patented elliptical design
outperforms and provides greater accuracy than traditional differential
pressure flow measurement devices. This differential pressure flow meter
is designed with a series of ports facing the upstream velocity pressures, as
well as flow sensing ports strategically located ahead of the trailing edge
flow separation.
The multi-ported, self-averaging flow element consists of an elliptical shape
with two independent flow sensing chambers. The impact velocity sensing
holes (high pressure) are located along the leading edge and the true
static sensing holes (low pressure) are on the exterior probe side. Model
PFA Fire Pump System comes with instrument shutoff valves with provisions to
accept a direct indicating meter.
SPECIFICATIONS
User Manual
True static
sensing holes
Impact velocity
sensing holes
Figure 1: PFA pressure sensing holes
Applications Liquids
Pipe Sizes 2…16 in. (5…406.4 mm)
Pressure 400 psi (2758 kPa) maximum
Temperature Gage 180° F (80° C) maximum
PFA Velocity Sensor 250° F (121° C) maximum
Accuracy ±1.75% of reading
Turndown Ratio 17:1 with no vacuum effect
Standard Components Y-type head, brass
Compression fitting;
2…5 in., brass
6…16 in., CS with SS ferrule
CS 3000 lb weld fitting, ASTM A105
316/316L SS Ellipse sensor
Instrument valves (2 per sensor), 1/4" male SAE flare brass ball
Polycarbonate ID tag with wire
Direct reading gage, brass body, 270° arc
Reynolds Number Greater than 75,000 maintains most accurate flow measurements
Less than 75,000 consult factory for estimated results
Double Support Double support required for the following Systems
Pipe Size Pump Ratings
4" 400 and 450 gpm
8" > 2000 gpm
10" > 2500 gpm
12" > 3000 gpm
16" > 5000 gpm
Table 1: PFA specifications
Page 3 April 2014