Danfoss VLT HVAC Drive FC 100 Series, Руководство по конструкции

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Full load
% F
ull load cur
ren
t
& speed
500
100
0
0 12,5 25 37,5 50Hz
200
300
400
600
700
800
4
3
2
1
175HA227.10
Figure 2.12
1 = VLT
®
HVAC Drive
2 = Star/delta starter
3 = Soft-starter
4 = Start directly on line power
Table 2.6
2.7.9 Using a Adjustable Frequency Drive
Saves Money
The example on the following page shows that a lot of
equipment is not required when a Adjustable frequency
drive is used. It is possible to calculate the cost of
installing the two different systems. In the example, the
two systems can be established at roughly the same price.
2.7.10 Without a Adjustable Frequency
Drive
The figure shows a fan system made in the traditional way.
D.D.C. =
Direct Digital
Control
E.M.S. =
Energy
Management
system
V.A.V. = Variable Air Volume
Sensor P = Pressure
Sensor
T
= Temperature
Table 2.7
Figure 2.13
2.7.11 With a Adjustable Frequency Drive
175HA206.11
Pump
Flow
Return
Supply
air
V.A.V
outlets
Duct
Mains
Pump
Return
Flow
Mains
Fan
Main
B.M.S
Local
D.D.C.
control
Sensors
Mains
Cooling section Heating section Fan section
Pressure
control
0-10V
or
0/4-20mA
Control
temperature
0-10V
or
0/4-20mA
Control
temperature
0-10V
or
0/4-20mA
VLT
M
- +
VLT
M
M
PT
VLT
x3 x3
x3
Figure 2.14 The figure shows a fan system controlled by
adjustable frequency drives.
Introduction to VLT® HVAC D...
VLT
®
HVAC Drive Design Guide
MG11BB22 - VLT
®
is a registered Danfoss trademark 2-13
2 2