29
Performance certified is for installation type A: Free inlet, Free outlet. Power rating (BHP) does not include transmission losses. Performance ratings include the effects
of a birdscreen. The sound ratings shown are loudness values in hemispherical sones at 5 ft. (1.5 m) in a hemispherical free field calculated per AMCA Standard 301.
Values shown are for installation type A: free inlet hemispherical sone levels.
0 2000 4000 6000 8000 10000
0
200
400
600
0 1000 2000 3000 4000 5000 6000
0.0
0.5
1.0
1.5
2.0
2.5
183-C
2 HP
1.5 HP
1 HP
3/4
HP
1/2 HP
1/3 HP
1/4 HP
1460
1335
1185
1140
1055
940
860
810
730
495
Static Pressure (in. wg)
Volume (cfm)
183-B
Volume (m
3
/hr)
Static Pressure (Pa)
RPM (Belt)
RPM (Direct)
RPM (Vari-Green)
HP
Density 0.075 lb/ft
3
Density 1.2 kg/m
3
D
O
N
O
T
S
E
L
E
C
T
T
O
T
H
E
L
E
F
T
O
F
T
H
I
S
S
Y
S
T
E
M
C
U
R
V
E
Roof Downblast - Exhaust
Belt & Direct Drive
GB-180 • G-183
Damper Size = 18 x 18 (457 x 457)
Roof Opening = 20½ x 20½ (521 x 521)
Shroud Thickness = 0.064 (1.6)
Motor Cover Thickness = 0.040 (1.0)
Curb Cap Thickness = 0.064 (1.6)
^Approximate Unit Weight G/GB = 108/142 lbs. (49/64 kg)
All dimensions in inches (millimeters). *May be greater depending on
motor. ^Weight shown is largest cataloged Open Drip-Proof motor.
1
3
⁄4 (44)
35
1
⁄2
(902)
5
1
⁄2 (140)
*28
(711)
30
(762)
Motor HP
Fan
RPM
Static Pressure in Inches wg
Belt Direct 0 0.125 0.25 0.5 0.75 1 1.25 1.5 1.75 2
180 183
1/4
VG-1
730
CFM
2839 2668 2469 1882
BHP
0.21 0.23 0.25 0.25
Sones
7.4 8.7 7.2 6.7
1/3 810
CFM
3150 2997 2832 2375
BHP
0.29 0.31 0.33 0.35
Sones
8.8 9.9 8.7 8.2
1/2
C-1/2 860
CFM
3344 3202 3049 2647 2015
BHP
0.35 0.36 0.39 0.42 0.4
Sones
10.1 10.8 9.8 9.1 8.1
940
CFM
3655 3527 3388 3052 2601
BHP
0.46 0.47 0.49 0.54 0.54
Sones
12.7 12.8 12.0 11.1 10.3
3/4
1000
CFM
3888 3769 3638 3339 2953 2387
BHP
0.55 0.57 0.58 0.64 0.66 0.63
Sones
15.2 14.7 13.7 13.0 11.9 11.1
VG-2
1055
CFM
4102 3990 3867 3596 3252 2811
BHP
0.65 0.67 0.68 0.74 0.77 0.77
Sones
16.2 15.7 14.9 14.0 12.9 12.4
1
B-1 1140
CFM
4433 4329 4216 3980 3684 3328 2856
BHP
0.81 0.84 0.85 0.93 0.96 0.98 0.95
Sones
17.9 17.4 16.8 16.0 15.1 14.3 13.6
1185
CFM
4608 4508 4401 4179 3900 3575 3178 2499
BHP
0.91 0.94 0.96 1.03 1.07 1.1 1.09 0.99
Sones
19.0 18.4 17.8 17.1 16.2 15.4 14.7 13.7
1
1
⁄2 1335
CFM
5191 5102 5010 4814 4599 4344 4052 3713 3262
BHP
1.31 1.33 1.36 1.41 1.49 1.54 1.57 1.56 1.51
Sones
22 22 21 21 19.9 19.2 18.7 18.2 17.6
2
1400
CFM
5444 5359 5273 5086 4892 4655 4401 4097 3747 3253
BHP
1.51 1.54 1.56 1.61 1.71 1.75 1.81 1.81 1.79 1.71
Sones
24 23 23 22 22 21 21 20 19.7 19.2
1460
CFM
5677 5596 5514 5336 5155 4938 4699 4426 4123 3765
BHP
1.71 1.74 1.77 1.81 1.93 1.97 2.03 2.05 2.05 2.02
Sones
26 25 24 24 23 23 22 22 22 21
C-860
-
RPM B-1140-RPM
MAXIMUM BHP AT A GIVEN RPM = (RPM/1149)
3
MAXIMUM RPM = 1460
TIP SPEED (ft/min) = RPM x 4.843
MAXIMUM MOTOR FRAME SIZE = 184T
Direct Drive RPM