5188236-BIM-A-0316
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Johnson Controls Unitary Products
Drive Selection
1.
Determine side or bottom supply air duct application.
2.
Determine desired airflow.
3.
Calculate or measure the amount of external static pressure.
4.
Using the operating point determined from steps 1, 2 & 3, locate this point on the appropriate supply air blower performance table. (Linear
interpolation may be necessary.)
5.
Noting the RPM and BHP from step 4, locate the appropriate motor and/or drive on the RPM selection table.
6.
Review the BHP compared to the motor options available. Select the appropriate motor and/or drive.
7.
Review the RPM range for the motor options available. Select the appropriate drive if multiple drives are available for the chosen motor.
8.
Determine turns open to obtain the desired operation point.
Example
1.
2200 CFM
2.
1.6 iwg
3.
Using the supply air blower performance table below, the following data point was located: 1478 RPM & 1.82 BHP.
4.
Using the RPM selection table below, Size X and Model Y is found.
5.
1.82 BHP exceeds the maximum continuous BHP rating of the 1.5 HP motor. The 2 HP motor is required.
6.
1478 RPM is within the range of the 2 HP drive.
7.
Using the 2 HP motor and drive, 2.5 turns open will achieve 1478 RPM.
Example Supply Air Blower Performance
Air Flow
(CFM)
Available External Static Pressure - IWG
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP
Field Supplied
Drive
Standard Drive Option
HIgh Static Drive Option
2000
907
1.00
990
1.07
1070
1.15
1146
1.23
1220
1.31
1291
1.40
1359
1.49
1425
1.58
1488
1.68
1550
1.77
2200
960
1.24
1043
1.31
1123
1.39
1199
1.47
1273
1.55
1344
1.64
1412
1.73
1478
1.82
1541
1.92
1602
2.01
2400
1015
1.51
1099
1.59
1178
1.66
1255
1.74
1329
1.83
1400
1.92
1468
2.01
1534
2.10
1597
2.19
1658
2.29
2600
1074
1.83
1157
1.90
1237
1.98
1314
2.06
1387
2.14
1458
2.23
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Table X: RPM Selection
Size
(Tons)
Model
HP
Max
BHP
Motor
Sheave
Blower
Sheave
5 Turns
Open
4 Turns
Open
3 Turns
Open
2 Turns
Open
1 Turn
Open
Fully
Closed
X
Y
1.5
1.73
1VL44
AK56
930
995
1060
1130
1195
1260
2
2.3
1VP56
AK56
1325
1395
1460
1525
1590
1660