Without a frequency converter
The figure shows a fan system made in the traditional way. D.D.C. = Direct Digital Control
E.M.S. = Energy Management sys-
tem
V.A.V. = Variable Air Volume
Sensor P = Pressure
Sensor T = Temperature
With a frequency converter
The figure shows a fan system controlled by VLT 6000 HVAC frequency converters.
VLT
®
6000 HVAC Series
MG.61.B5.02 - VLT
®
is a registered Danfoss trademark 15
Introduction to HVAC