Danfoss VLT Refrigeration Drive FC 103 Design Manual page 18

Product Overview
H
(mwg)
s
60
2 2
50
B
40
30
20
10
0
P
(kW)
shaft
60
50
40
30
20
10
0
Illustration 2.4 Energy Consumption at Different Speeds
Flow Distribution
rate
% Duration
[m 3 /h]
350 5
300 15
250 20
200 20
150 20
100 20
Σ
10
0
Table 2.2 Result
1) Power reading at point A1.
2) Power reading at point B1.
3) Power reading at point C1.
16
A
1350rpm
C
1050rpm
750rpm
100 200 300
A
1350rpm
B 1
1050rpm
C 1
750rpm
100 200 300
Valve regulation
Power Consump- Power Consump-
tion
[h] [kW] [kWh] [kW]
438 18.615
42.5 1) 42.5
1314 38.5 50.589 29.0
1752 35.0 61.320 18.5
1752 31.5 55.188 11.5
1752 28.0 49.056
1752 40.296
23.0 2) 3.5
8760 – 275.064
Danfoss A/S © 08/2015 All rights reserved.
®
VLT Refrigeration Drive FC 103
2.1.5 Improved Control
Use a frequency converter to improve control of the flow
or pressure of a system.
Use a frequency converter to vary the speed of the
compressor, fan, or pump, obtaining variable control of
flow and pressure.
Furthermore, a frequency converter can quickly adapt the
1650rpm
speed of the compressor, fan, or pump to new flow or
pressure conditions in the system.
Obtain simple control of process (flow, level, or pressure)
utilising the built-in PI control.
( 3 )
m /h
400
2.1.6 Star/Delta Starter or Soft Starter
When large motors are started, it is necessary in many
countries to use equipment that limits the start-up current.
In more traditional systems, a star/delta starter or soft
1
starter is widely used. If a frequency converter is used,
1650rpm
such motor starters are not required.
As illustrated in Illustration 2.5, a frequency converter does
not consume more than rated current.
800
700
( )
400 m 3 /h
600
500
Frequency
400
converter
300
control
200
tion
[kWh]
100
18.615
1)
0
38.106
32.412
20.148
6.5 11.388
1 VLT ®
Refrigeration Drive FC 103
6.132
3)
2 Star/delta starter
– 26.801
3 Soft starter
4 Start directly on mains
Illustration 2.5 Start-up Current
3
2
1
0 12,5 25
4
37,5 50Hz
Full load
& speed
MG16G202