Roof downblast - exhaust belt drive gb-300hp – Greenheck Fan Centrifugal Roof Downblast Exhaust Fans GB User Manual
Page 39
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39
Roof Downblast - Exhaust
Belt Drive
GB-300HP
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
OT
S
EL
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
Motor
HP
Fan
RPM
Static Pressure in Inches wg
0.5
0.75
1
1.25
1.5
1.75
2
2.25
2.5
2.75
300HP
1/2
460
CFM
2912
BHP
0.41
Sones
9.7
495
CFM
3602
BHP
0.53
Sones
10.3
3/4
565
CFM
4662
3600
BHP
0.77
0.76
Sones
11.8
10.4
1
620
CFM
5398
4652
3309
BHP
1.01
1.04
0.94
Sones
13.4
12.3
10.6
1
1
⁄
2
710
CFM
6542
5954
5269
4221
BHP
1.48
1.53
1.55
1.47
Sones
17.2
16.0
15.3
13.4
2
748
CFM
7013
6462
5889
5027
BHP
1.71
1.78
1.81
1.78
Sones
18.8
17.5
17.0
15.7
785
CFM
7460
6943
6402
5737
4800
BHP
1.96
2.04
2.08
2.10
2.00
Sones
20
19.1
18.5
17.9
16.2
3
840
CFM
8107
7642
7146
6636
5922
4992
BHP
2.37
2.46
2.52
2.57
2.56
2.43
Sones
23
22
21
21
19.7
18.0
895
CFM
8746
8328
7870
7394
6892
6150
5245
BHP
2.84
2.95
3.03
3.07
3.11
3.08
2.92
Sones
25
24
23
23
23
22
19.8
5
980
CFM
9722
9356
8951
8531
8094
7657
7029
6264
5222
BHP
3.68
3.81
3.90
3.99
4.03
4.08
4.09
3.95
3.69
Sones
32
31
29
28
27
26
25
24
23
1065
CFM
10688
10351
10006
9621
9233
8831
8429
7903
7255
6543
BHP
4.67
4.81
4.94
5.04
5.12
5.17
5.23
5.24
5.17
5.01
Sones
44
42
37
37
36
35
33
31
30
29
MAXIMUM BHP AT A GIVEN RPM = (RPM/613)
3
MAXIMUM RPM = 1065
TIP SPEED (ft/min) = RPM x 7.985
MAXIMUM MOTOR FRAME SIZE = 184T
50
(1270)
8
1
⁄
4
(210)
*36
(914)
40
(1016)