Drive Selection; Example Supply Air Blower Performance - York R-410A Technical Manual

Drive Selection

1. Determine Upflow or Horizontal supply 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. 3250 CFM
2. 1.4 iwg
3. Using the supply air blower performance table below, the following data point was located: 1100 RPM & 1.8 BHP.
4. Using the RPM selection table below, Model X is found.
5. 1.8 BHP exceeds the maximum continuous BHP rating of the 1.5 HP motor. The 2 HP motor is required.
6. 1100 RPM is within the range of the 2 HP drives.
7. Using the 2 HP motor and drive, 1 turn open will achieve 1128 RPM.
Airflow Performance

Example Supply Air Blower Performance

(CFM) 0.2 0.4
RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP RPM BHP
3000 696 0.9 757
3250 729 1.1 790
3500 766 1.3 826
RPM Selection
Unit Model HP
Std. 1.5
X
HS 2
Johnson Controls Unitary Products
Available External Static Pressure - IWG
0.6 0.8
Standard 1.5 HP & Drive
1.1 822 1.2 891 1.3
1.3 855 1.4 924 1.5
1.5 892 1.6 953 1.6
Max Motor Blower
BHP Sheave Sheave
1.73 1VL40 AK69
2.30 1VL40 AK56
1.0 1.2
961 1.3 1019 1.5 1077
984 1.6 1042 1.7 1100
1010 1.8 1069 1.9 1127
6 Turns 5 Turns 4 Turns
Open Open Open
N/A 690 743
N/A 863 929
505428-YTG-V-0417
1.4 1.6 1.8
High Static 2 HP & Drive
1.6 1135 1.8
1.8 1159 2.0
2.0
3 Turns 2 Turns 1 Turn
Open Open Open
796 849 902
995 1062 1128
2.0
Fully
Closed
955
1194
61