Example Of Application - Speed Control Of Fan In Ventilation System - Danfoss VLT 6000 series Operating Instructions Manual

Example of application - Speed control of
fan in ventilation system
The AHU installation is able to distribute air throughout
the building or to one or several parts of a building.
Normally, an AHU installation consists of a fan and
a motor that supply air, a fan scroll and a duct
system with filters. If centralised air distribution is
applied, the efficiency of the installation will increase
and major energy savings can be made.
A VLT 6000 HVAC enables excellent control and
monitoring, thereby ensuring perfect conditions
in the building at all times.
Set the following parameters:
Par. 100 Configuration
Par. 221 Warning: Low current, I
Par. 224 Warning: High frequency, f
Par. 300 Terminal 16 Digital inputs
Par. 302 Terminal 18 Digital inputs
Par. 308 Terminal 53, analogue input voltage
Par. 309 Terminal 53, min. scaling
Par. 310 Terminal 53, max. scaling
Par. 319 Output
Par. 323 Relay 1
Par. 326 Relay 2
Par. 409 Function at no load
MG.61.A5.02 - VLT is a registered Danfoss trademark
This example shows an application with Run permissive,
warning against no load and warning for filter change.
The Run permissive function ensures that the frequency
converter will not start the motor until the discharge
damper has opened. If the V-belt to the fan breaks
and if the filter is to be changed, this application
will also give a warning on an output.
Open loop [0]
Depends on unit
LOW
HIGH
Run permissive [8]
Start [1]
Reference [1]
0 v
10 v
Output frequency greater than f
Start command active [27]
Alarm or warning [12]
Warning [1]
®
VLT 6000 HVAC Series
par. 224
HIGH
11