Star/Delta Starter Or Soft Starter Not Required; Using A Frequency Converter Saves Money - Danfoss VLT HVAC Basic Drive FC 101 Design Manual

Product Overview
3.1.7 Star/Delta Starter or Soft Starter not
Required
When larger motors are started, it is necessary in many
countries to use equipment that limits the start-up current.
3 3
In more traditional systems, a star/delta starter or soft
starter is widely used. Such motor starters are not required
if a frequency converter is used.
As illustrated in Illustration 3.8, a frequency converter does
not consume more than rated current.
800
700
600
500
400
300
200
100
0
0
1 VLT ®
HVAC Basic Drive FC 101
2 Star/delta starter
3 Soft starter
4 Start directly on mains
Illustration 3.8 Start-up Current
16
VLT
4
3
2
1
12,5 25 37,5
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®
HVAC Basic Drive FC 101
3.1.8 Using a Frequency Converter Saves
Money
The example in chapter 3.1.9 Without a Frequency Converter
shows that a frequency converter replaces other
equipment. It is possible to calculate the cost of installing
the 2 different systems. In the example, the 2 systems can
be established at roughly the same price.
Use the VLT
chapter 1.5 Additional Resources to calculate the cost
savings that can be achieved by using a frequency
converter.
50Hz
Full load
& speed
®
Energy Box software that is introduced in
MG18C702