06-06
the altitude, temperature, fan inlet and discharge
conditions, and AMCA 201 System Effect Factors.
The fan
selection shall be made within a stable range of operation
at an optimum static efficiency.
The fan motor W (BHP),
required at the operating point on the fan curves, shall be
increased by 10% for drive losses and field conditions to
determine the fan motor horsepower. The fan motor shall be
selected within the rated name plate capacity and without
relying upon NEMA Standard Service Factor. See VA criteria
for the energy efficient motors.
7. Motor Voltages: Motor Voltages on equipment schedules shall
conform to NEMA/ANSI standard as follows:
Table 3-6
System Voltage (Transformers)
Utilization Voltage (Motors)
Nominal
With 4% Drop
Standard (For Schedule)
120
115.2
115
208
199.7
200
240
230.4
230
480
460.8
460
600
576.0
575
2400
--
2300
4160
--
4000
B. REFRIGERATION EQUIPMENT SIZING: The capacity of the refrigeration
system including accessories (condenser and chilled water pumps,
cooling tower, piping, etc.) shall be based on the sum of the total
cooling requirements of all connected air handling units. See
paragraphs 3.14A4 and 3.14A5 for the derivation of the total cooling
requirements of an air handling unit. To the chilled water system
capacity, thus established, no additional safety factor is required.
2.10 DUCT SIZING CRITERIA
A. LOW VELOCITY DUCTWORK: All supply air ductwork on the downstream side
of the air terminal units, return air ductwork, and exhaust air
ductwork shall be low velocity/low pressure type. The maximum
velocity and the static pressure drop shall be limited to 1500 feet
per minute and 0.1 inch of water gage (WG) per 100 equivalent feet of
duct length, respectively. The supply air ductwork between the fan
discharge and the inlet of the air terminal units can be low velocity
type (if possible) unless the space conditions do not permit so.
10
Previous Page
