Specifications

Full load
% Full load current
& speed
500
100
0
012,52537,5 50Hz
200
300
400
600
700
800
4
3
2
1
175HA227.10
Illustration 2.8 Current Consumption with a Frequency
Converter
1 = VLT
®
HVAC Drive
2 = Star/delta starter
3 = Soft-starter
4 = Start directly on mains
Table 2.6 Legend to Illustration 2.8
2.7.9 Using a Frequency Converter Saves
Money
The frequency converter eliminates the need for some
equipment that would normally be used. It is possible to
calculate the cost of installing the two different systems.
The two systems shown in Illustration 2.9 and
Illustration 2.10 can be established at roughly the same
price.
2.7.10 Without a Frequency Converter
M
-+
M
M
x6 x6
x6
175HA205.12
Valve
posi-
tion
Starter
Fuses
LV
supply
P. F.C
Flow
3-Port
valve
Bypass
Return
Control
Supply
air
V.A.V
outlets
Duct
P. F.C
Mains
Fuses
Starter
Bypass
supply
LV
Return
valve
3-Port
Flow
Control
Valve
posi-
tion
Starter
Power
Factor
Correction
Mains
IGV
Mechanical
linkage
and vanes
Fan
Motor
or
actuator
Main
B.M.S
Local
D.
D.C.
control
Sensors
PT
Pressure
control
signal
0/10V
Temperature
control
signal
0/10V
Control
Mains
Cooling section Heating section
Fan sectionInlet guide vane
Pump Pump
Illustration 2.9 Traditional Fan System
DDC Direct Digital Control
VAV Variable Air Volume
Sensor P Pressure
EMS Energy Management System
Sensor T Temperature
Table 2.7 Legend to Illustration 2.9
Introduction VLT® HVAC Drive FC 102 Design Guide
22 MG16C102 - Rev. 2013-08-20
2
2