Daikin UATN60CGXY1, Техническое руководство

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Selection Process
Selection Process
Drive Package
The following are the design requirements for UATN60C unit:
Model: UATN60C
Supply Air Quantity = 2000 CFM
External Static Pressure = 180 Pa
Step 1: From the fan curve (at 2000 CFM),
Standard operating system;
Internal Static Pressure = 115 Pa
Step 2: Therefore at 2000 CFM and 180 Pa external static pressure,
Total Static Pressure = 180 + 115 Pa
= 295 Pa
Step 3: From the blower curve, the design requirement calls for RPM about 1200 RPM.
From the table:
Motor pulley = 100 mm
Blower pulley = 140 mm
Motor RPM = 1430
In order to obtain 1200 RPM, we calculate the new blower pulley as:
(while maintaining the motor pulley)
Db = 100 x (1430/1200)
= 119.17 mm
Let us take close approximation of 120 mm diameter pulley size
Recheck, with Db =
120 mm
Blower pulley = 1430 x (100/120)
=
1192 RPM
We thus need to change the blower pulley from 140 mm to 120 mm in order to obtain the higher operating
static pressure.
Step 4: When the pulley is changed, the V-belt length must be rechecked. We have for horizontal air throw
configuration:
V-belt length, L = 2C + 1.57 (Db + Dm)
= (2x165) + 1.57(120+100)
= 675.4
We thus can use a belt with a length of 680 mm
where, C = distance between the centres of the two pulleys
Db = diameter of blower pulley
Dm = diameter of motor pulley
Step 5: From the blower curve, we can also notice that the motor power input has maintained within the current
operating range of the standard unit’s motor.
Summary:
i) Fan motor kW = 0.75 kW
ii) Blower pulley diameter = 120 mm
iii) V-belt size =
680
mm
Note: Factory supplied rooftop is only with standard drive package.
All other changes are only given as example and need to be field supply.