350
5
438
42.5
18.615
42.5
18.615
300
15
1314
38.5
50.589
29.0
38.106
250
20
1752
35.0
61.320
18.5
32.412
200
20
1752
31.5
55.188
11.5
20.148
150
20
1752
28.0
49.056
6.5
11.388
100
20
1752
23.0
40.296
3.5
6.132
Σ
100
8760
–
275.064
–
26.801
3.1.1.5 Better Control
If a drive is used for controlling the flow or pressure of a system, improved control is obtained.
A drive can vary the speed of the fan or pump, obtaining variable control of flow and pressure. Furthermore, a drive can quickly
adapt the speed of the fan or pump to new flow or pressure conditions in the system.
Simple control of process (flow, level, or pressure) utilizing the built-in PI control.
3.1.1.6 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. In more tradi-
tional systems, a star/delta starter or soft starter is widely used. Such motor starters are not required if a drive is used.
As shown in the following illustration, a drive does not consume more than rated current.
F ull load
%
F
ul
l
lo
a
d
c
u
r r e
n
t
& speed
500
100
0
0
12,5
25
37,5
50H z
200
300
400
600
700
800
4
3
2
1
e
7
5
h
a
2
2
7
.1
0
Illustration 8: Start-up Current
1
VLT® Flow Drive FC 111
2
Star/delta starter
3
Soft starter
4
Start directly on mains
3.1.1.7 Using a Drive Saves Money
3.1.1.8 Traditional Fan System without a Drive
and
3.1.1.9 Fan System Controlled by Drives
ces 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® Energy Box software that is introduced in
chapter Additional Resources
to calculate the cost savings that can be ach-
ieved by using a drive.
AJ363928382091en-000101 / 130R0983
18 | Danfoss A/S © 2021.04
Product Overview
VLT® Flow Drive FC 111
Design Guide
