FC101 Design Guide

3.1.5 Example with Varying Flow over 1
Year
This example is calculated based on pump characteristics
obtained from a pump datasheet.
The result obtained shows energy savings of more than
50% at the given ow distribution over a year. The
payback period depends on the price per kWh and the
price of frequency converter. In this example, it is less than
a year when compared with valves and constant speed.
Energy savings
P
shaft
= P
shaft output
500
[h]
t
1000
1500
2000
200100 300
[m
3
/h]
400
Q
175HA210.11
Figure 3.6 Flow Distribution over 1 Year
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
200100 300
(m
3
/h)
(
m
3
/h)
400
750rpm
1050rpm
1350rpm
1650rpm
P
shaft
C
1
B
1
A
1
Figure 3.7 Energy
m
3
/
h
Distri-
bution
Valve regulation
Frequency converter
control
% Hours Power
Consump-
tion
Power
Consump-
tion
A
1
- B
1
kWh A
1
- C
1
kWh
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
Table 3.2 Result
Product Overview
VLT
®
HVAC Basic Drive FC 101
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