DFO-103 - page 8

ing the performance of aSize 135
fan. For a desired duty of 5,500
CFM (A) at 6" SP (B), the fan will
need to run at 3753 RPM (C) and
use7.22BHP (D).
Pages 9 thru 47 contain multi-rating
tables for every fan size. Each page
provides data for one size ranging
from 1/4" static pressure (SP) up to
20" SP.Volume is listed in cubic feet
perminute, (CFM) andoutlet velocity
(VEL). Under each SP rating is the
speed (RPM), andhorsepower (BHP)
required for eachcorrespondingCFM
rating. Simply interpolate between
ratings for any valuenot listed.
Ratings in bold italic type on each
pageare in thehighefficiency selec-
tion range. (Refer to the graph on
Classes I, II and III are indicated by
different color tints,
Whenadesiredduty fallsbetween
published ratings, exact speedand
horsepower can be interpolated.
For 4,500CFMat 4", useavailable
Table Data (E) and interpolate as
shownbelow.TheOutletVelocity is
2381 and the fan will run at 3068
1,2,3,4,5,6,7 9,10,11,12,13,14,15,16,17,18,...52
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