Roof downblast - exhaust belt drive gb-300 – Greenheck Fan Centrifugal Roof Downblast Exhaust Fans GB User Manual
Page 38
38
Roof Downblast - Exhaust
Belt Drive
GB-300
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.
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.
1
3
⁄
4
(44)
Damper Size = 30 x 30
(762 x 762)
Roof Opening = 32½ x 32½
(826 x 826)
Shroud Thickness = 0.064
(1.6)
Motor Cover Thickness = 0.051
(1.3)
Curb Cap Thickness = 0.064
(1.6)
^Approximate Unit Weight = 320 lbs.
(145 kg)
All dimensions in inches (millimeters). *May be greater depending on
motor. ^Weight shown is largest cataloged Open Drip-Proof motor.
DO
N
O
T
S
E
L
E
C
T
T
O
T
H
E
L
E
F
T
O
F
T
H
IS
S
Y
S
T
E
M
C
U
R
V
E
Static Pr
essur
e (in. wg)
Static Pr
essur
e (Pa)
Volume (cfm x 1000)
3
Volume (m /hr x 1000)
RPM
(Belt)
HP
Density 0.075 lb/ft
3
Density 1.2 kg/m
3
50
(1270)
8
1
⁄
4
(210)
*36
(914)
40
(1016)
Motor
HP
Fan
RPM
Static Pressure in Inches wg
0
0.125
0.25
0.5
0.75
1
1.25
1.5
1.75
2
300
1/3
300
CFM
4859
3976
BHP
0.18
0.19
Sones
9.3
5.3
365
CFM
5912
5222
4340
BHP
0.33
0.35
0.35
Sones
9.2
6.2
5.7
1/2
420
CFM
6803
6222
5537
BHP
0.50
0.52
0.53
Sones
9.6
8.0
7.0
3/4
475
CFM
7694
7197
6616
5095
BHP
0.72
0.75
0.77
0.74
Sones
11.4
10.6
9.6
8.1
1
530
CFM
8585
8150
7640
6456
4195
BHP
1.00
1.04
1.06
1.07
0.91
Sones
13.4
12.9
12.2
10.7
9.4
1
1
⁄
2
600
CFM
9719
9334
8907
7952
6721
BHP
1.45
1.49
1.53
1.55
1.52
Sones
15.9
15.4
14.9
13.8
12.2
2
665
CFM
10772
10425
10060
9228
8269
7025
BHP
1.97
2.02
2.06
2.11
2.11
2.03
Sones
18.8
18.2
17.7
16.8
15.7
13.7
3
713
CFM
11549
11226
10901
10129
9297
8283
6691
BHP
2.43
2.48
2.53
2.59
2.61
2.57
2.38
Sones
21
20
19.6
18.9
18.0
16.4
13.7
760
CFM
12311
12007
11704
10997
10242
9369
8293
6437
BHP
2.94
3.00
3.05
3.13
3.16
3.15
3.06
2.76
Sones
23
22
21
21
19.8
18.6
16.8
14.0
5
825
CFM
13363
13084
12804
12175
11501
10770
9909
8885
7128
BHP
3.76
3.82
3.88
3.97
4.02
4.05
4.01
3.90
3.56
Sones
25
25
24
24
23
22
20
18.7
16.1
890
CFM
14416
14157
13898
13335
12716
12073
11379
10536
9568
7963
BHP
4.73
4.79
4.85
4.96
5.03
5.06
5.09
5.02
4.89
4.54
Sones
28
28
28
27
26
25
24
22
21
18.7
MAXIMUM BHP AT A GIVEN RPM = (RPM/517)
3
MAXIMUM RPM = 890
TIP SPEED (ft/min) = RPM x 7.985
MAXIMUM MOTOR FRAME SIZE = 184T