175HA209.11
60
50
40
30
20
10
H
s
0
100
200
300
400
(mwg)
B
C
A
750rpm
1050rpm
1350rpm
1650rpm
0
10
20
30
(kW)
40
50
60
200
100
300
(
m
3
/h
)
(
m
3
/h
)
400
750rpm
1050rpm
1350rpm
1650rpm
P
shaft
C
1
B
1
A
1
Illustration 2.4 Energy Consumption at Different Speeds
Flow
rate
Distribution
Valve regulation
Frequency
converter
control
%
Duration
Power Consump-
tion
Power Consump-
tion
[m
3
/h]
[h]
[kW]
[kWh]
[kW]
[kWh]
350
5
438
42.5
1)
18.615
42.5
1)
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
2)
40.296
3.5
3)
6.132
Σ
10
0
8760
–
275.064
–
26.801
Table 2.2 Result
1) Power reading at point A1.
2) Power reading at point B1.
3) Power reading at point C1.
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
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.
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
starter is widely used. If a frequency converter is used,
such motor starters are not required.
As illustrated in
, a frequency converter does
not consume more than rated current.
Full load
% F
ull-load cur
ren
t
& speed
500
100
0
0
12,5
25
37,5
50Hz
200
300
400
600
700
800
4
3
2
1
175HA227.10
1 VLT
®
Refrigeration Drive FC 103
2 Star/delta starter
3 Soft starter
4 Start directly on mains
Illustration 2.5 Start-up Current
Product Overview
VLT
®
Refrigeration Drive FC 103
16
Danfoss A/S © 08/2015 All rights reserved.
MG16G202
2
2
Содержание VLT FC 103
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