Emerson CW026 Design Manual page 118

Guide Specifications—Chilled Water Environmental Control System
2.4 FAN SECTION
Electronically Commutated (EC) Fans
The fans shall be plug/plenum type, single-inlet and shall be dynamically balanced. The drive package
shall be direct drive, electronically commutated and variable speed. The fans shall be located to draw air
over the A-frame coil to ensure even air distribution and maximum coil performance. EC fans shall be
available on downflow models, and fans may be lowered into a raised floor with a minimum height of 24 in.
(610 mm). EC fans may operate within the Liebert CW cabinet, instead of under the floor.
EC fans shall be available on upflow models and fans shall operate outside the unit in a factory-provided
plenum.
• Upflow CW026–114: The fan motor(s) shall be 4.0 hp (3.0 kW) with maximum speed of 1520 rpm;
quantity 1 for CW026–41; 2 for CW051–084; 3 for CW106–114.
• Downflow CW026–CW041: The fan motor shall be 4.0 hp (3.0 kW) with a maximum operating speed
of 1520 rpm; quantity 1.
• Downflow CW051 and CW060: The fan motors shall be 3.4 hp (2.5 kW) with a maximum operating
speed of 1700 rpm; quantity 2. (Power rating for 380–480V. For 200–240V, power is 3.6 hp [2.7 kW]).
• Downflow CW076–CW089: The fan motors shall be 4.0 hp (3.0 kW) with a maximum operating speed
of 1520 rpm; quantity 2.
• Downflow CW106–CW114: The fan motors shall be 4.0 hp (3.0 kW) with a maximum operating speed
of 1520 rpm; quantity 3.
• CW146: The fan motors shall be 3.7 hp (2.8 kW) with a maximum operating speed of 1230 rpm;
quantity 3.
• CW181: The fan motors shall be 4.9 hp (3.7 kW) with a maximum operating speed of 1370 rpm;
quantity 3.
Forward Curved Blower
The blower section shall be designed for ___ CFM (CMH) at an external static pressure
of ___ in. wg. (Pa). The fan shall be the centrifugal type, double-width, double-inlet, and shall be factory-
balanced as a completed assembly. The shaft shall be heavy-duty steel with self-aligning ball bearings with
a minimum lifespan of 100,000 hours.
The fans shall be located to draw air over the A-frame coil to ensure even air distribution and maximum coil
performance. The fan motor shall be ____ hp at 1750 rpm at 60 Hz (1450 rpm at 50 Hz) and mounted on
an adjustable slide base. The drive package shall be two-belt, variable speed, sized for 200% of the fan
motor horsepower.
2.5 CHILLED WATER CONTROL VALVE
The water circuit shall include a 3-way (2-way) modulating valve. The Liebert iCOM shall position the valve
in response to room conditions. Cooling capacity shall be controlled by by-passing chilled water around the
coil.
2.5.1 High Pressure Chilled Water Control Valve—Optional
The chilled water circuit shall include a 3-way (2-way) high-pressure modulating valve. The valve shall be
designed for up to 400 PSI (2758 kPa) water pressure.
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Liebert CW System Design Manual 108