Dwyer FLST - Manual

Series FLST Duct Mounted Airflow Measurement Station
Specifications - Installation and Operating Instructions
Bulletin F-FLST
DWYER INSTRUMENTS, INC.
Phone: 219/879-8000 www.dwyer-inst.com
P.O. BOX 373 • MICHIGAN CITY, INDIANA 46361, U.S.A. Fax: 219/872-9057 e-mail: [email protected]
SPECIFICATIONS
Accuracy: Within 2% of actual flow when installed in accordance with
published recommendations.
Velocity Range: 100 to 10,000 fpm (0.51 to 51 m/s).
Wetted Material: Elements 6063-T5 anodized aluminum; Casings 16 ga
G90 galvanized steel.
Temperature Limits: Galvanized Casings and Aluminum Elements
350°F (177°C) continuous operation (in air) 400°F (204°C) intermittent
operation (in air).
Humidity: All Airflow Stations 0 to 100% non condensing.
Process Connections: 1/4˝ compression fittings.
TOTAL PRESSURE
(T.P.) TAKEOFF
STATIC PRESSURE
(S.P.) TAKEOFF
AIRFLOW
(D)
(F)
(L)
(L + 2.5˝)
TOTAL PRESSURE
(T.P.) TAKEOFF
.25˝ RADIUS
BEADED EDGE (TYP)
STATIC PRESSURE
(S.P.) TAKEOFF
TOTAL PRESSURE
(T.P.) TAKEOFF
STATIC PRESSURE
(S.P.) TAKEOFF
AIRFLOW
(L=5˝)
(H)
(F)
(W)
STATION
SIZE “D”
8˝ - 15˝
16˝ - 44˝
45˝ - 72˝
73˝ & OVER
FLANGE
THICKNESS
.064˝
.064˝
.188˝
.188˝
FLANGE
SIZE “F”
1˝
1-1/2˝
1-1/2˝
2˝
CASING
LENGTH “L”
6˝
6˝
10˝
12˝
CIRCULAR FLANGE
OVAL FLANGE (OPTIONAL)
RECTANGULAR FLANGE
FLANGE
SIZE “F”
1-1/2˝
2˝
STATION SIZE
“H” OR “W”
8˝ - 72˝
73˝ & OVER
DIMENSIONS
The Series FLST Airflow Measurement Station consists of single or
multiple airflow elements, factory mounted and pre-piped in a casing
designed for flanged connection to the ductwork. Standard materials con-
sist of a G90 galvanized casing and 6063-T5 anodized aluminum flow sen-
sors, suitable for most HVAC applications.
The airflow averaging element, utilized in the FLST, is a head type device,
which generates a differential (velocity) pressure signal similar to the orifice,
venturi, and other head producing primary elements. The FLST is con-
structed so that strategically located sensing ports (based on duct size)
continually sample the total and static pressures, when inserted normal to
flow. The total pressures sensed by the upstream ports are continually
averaged within the element in an isolated chamber. The static sensing
ports (located where the influence of the velocity head is zero) are averaged
in a second isolation chamber. Multiple elements are manifolded together
for connection to a differential measurement device (gage, transmitter, etc.)
for flow measurement and indication purposes.
NOTE: All oval flow stations without flange have a
casing length of 5˝.
STATION
WIDTH “W”
UP TO 44˝
OVER 44˝
FLANGE
THICKNESS
.064˝
.188˝
FLANGE
SIZE
1-1/2˝
1-1/2˝
CASING
LENGTH “L”
6˝
8˝
F-FLST.qxd:F-flst.qxd 1/14/09 9:51 AM Page 1