21
Performance certified is for installation Type B - Free inlet, Ducted outlet. Power rating (Bhp) does not include transmission losses. Performance ratings do not include the
effects of appurtenances (accessories). The AMCA Certified Ratings Seal applies to air performance only.
Wheel Diameter = 20
(508)
Shaft Diameter = 1
1
⁄
4
(32)
Outlet Area = 2.40 ft
2
(0.223 m
2
)
Mounting Hole Size = 5/8
(16)
^Approximate Unit Weight = 405 lb
(184 kg)
All dimensions in inches
(millimeters)
For additional discharge positions see page 12
^Weight shown is largest cataloged Open Drip Proof motor
SFB-20 - Belt Drive
CFM
OV
Static Pressure in Inches wg
0.25
0.5
0.75
1
1.25
1.5
1.75
2
2.5
2.75
3275
1362
RPM
320
402
BHP
0.37
0.53
Sones
8.1
9.1
3800
1581
RPM
343
420
487
BHP
0.51
0.70
0.90
Sones
10.3
10.1
11.3
4325
1799
RPM
369
440
503
561
613
BHP
0.70
0.90
1.13
1.36
1.61
Sones
11.3
11.5
12.6
13.1
14.6
4850
2018
RPM
396
462
521
576
628
676
BHP
0.92
1.15
1.39
1.64
1.91
2.19
Sones
12.3
13.4
13.7
13.9
15.0
16.7
5375
2236
RPM
424
485
542
594
642
689
733
BHP
1.19
1.45
1.71
1.99
2.26
2.56
2.87
Sones
14.0
15.4
14.7
14.5
15.3
16.9
18.6
5900
2455
RPM
454
511
564
614
661
704
747
788
BHP
1.52
1.80
2.08
2.38
2.68
2.98
3.30
3.64
Sones
16.1
16.8
15.5
15.3
15.5
17.3
19.0
21
6425
2673
RPM
484
537
587
634
679
722
762
801
877
911
BHP
1.90
2.22
2.52
2.83
3.15
3.49
3.81
4.15
4.89
5.26
Sones
18.6
18.4
16.8
16.1
16.5
18.0
19.8
21
24
26
6950
2892
RPM
515
565
612
657
700
741
780
818
890
925
BHP
2.36
2.69
3.02
3.36
3.70
4.04
4.41
4.76
5.51
5.92
Sones
20
19.8
18.5
17.0
18.0
19.3
21
22
25
26
7475
3110
RPM
546
593
638
681
722
761
799
836
904
938
BHP
2.88
3.24
3.59
3.95
4.30
4.68
5.05
5.44
6.20
6.61
Sones
22
21
20
19.2
19.5
21
22
24
27
28
8000
3329
RPM
578
622
665
705
745
782
819
854
922
BHP
3.47
3.86
4.24
4.61
5.00
5.38
5.79
6.18
7.02
Sones
24
23
22
22
22
23
24
25
29
8525
3547
RPM
610
652
692
731
769
805
840
875
940
BHP
4.14
4.55
4.96
5.37
5.77
6.18
6.59
7.02
7.89
Sones
26
24
24
24
24
25
26
28
31
Do
n
ot
s
el
ec
t
to
t
h
e
le
ft
o
f
th
is
s
y
s
te
m
c
u
rv
e
cfm
36
1
⁄
8
(918)
23
3
⁄
4
(603)
15
7
⁄
8
(403)
2
(51)
21
1
⁄
8
(537)
19
1
⁄
2
(495)
35
(889)
37
(940)
33
5
⁄
8
(854)
22
(559)
1
1
⁄
2
(38)
27
3
⁄
8
(695)
24
1
⁄
2
(622)
46
(1168)
21
1
⁄
2
(546)
14
7
⁄
8
(378)
25
5
⁄
8
(651)
Maximum BHP at given RPM = (RPM/485)
3
(Maximum KW at a given RPM = (RPM/535)
3
)
Maximum RPM = 950 and Minimum RPM = 270
Tip Speed (ft/min.) = RPM x 5.24
(Tip Speed (m/s) = RPM x 0.0266)
Maximum Motor Frame Size = 215T
SFB-20
