Specifications

2.5.10 With a Frequency Converter
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
V LT
M
- +
V LT
M
M
PT
V LT
x3 x3
x3
Illustration 2.6 Fan System Controlled by Frequency Converters
2.5.11
Application Examples
The next few pages provide typical examples of applications within HVAC.
If you would like to receive further information about a given application, please ask your Danfoss supplier for an
information sheet that gives a full description of the application. The following application notes can be downloaded from
the Danfoss web page, www.VLT-literature.com.
Variable Air Volume
Ask for The Drive to...Improving Variable Air Volume Ventilation Systems, MN.60.A1.02
Constant Air Volume
Ask for The Drive to...Improving Constant Air Volume Ventilation Systems, MN.60.B1.02
Cooling Tower Fan
Ask for The Drive to...Improving fan control on cooling towers, MN.60.C1.02
Condenser pumps
Ask for The Drive to...Improving condenser water pumping systems, MN.60.F1.02
Primary pumps
Ask for The Drive to...Improve your primary pumping in primay/secondary pumping systems, MN.60.D1.02
Secondary pumps
Ask for The Drive to...Improve your secondary pumping in primay/secondary pumping systems, MN.60.E1.02
2.5.12 Variable Air Volume
VAV or Variable Air Volume systems, control both the ventilation and temperature to satisfy the requirements of a building.
Central VAV systems are considered to be the most energy efficient method to air condition buildings. By designing central
systems instead of distributed systems, a greater efficiency can be obtained.
The efficiency comes from utilizing larger fans and larger chillers which have much higher efficiencies than small motors
and distributed air-cooled chillers. Savings are also seen from the decreased maintenance requirements.
Introduction to VLT HVAC Ba... VLT HVAC Basic Drive Design Guide
MG.18.C2.02 - VLT
®
is a registered Danfoss trademark 15
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