VLT
®
6000 HVAC
9
MG.60.B1.02 - VLT is a registered Danfoss trademark
Introduction to
HV
AC
Example with varying flow over 1 year
The example below is calculated on the basis of pump
characteristics obtained from a pump data-sheet. (45
kW). The same examples of calculations can be used
in the case of fan characteristics.
The result obtained is savings in excees of 50% at the
■
Energy savings
This figure compares flow regulation via valves and
without speed control with flow regulation via a
frequency converter.
P
shaft
= P
shaft output
Flow distribution over 1 year
given flow distribution over a year, corresponding to
8,760 hours.
Typically, the example calculated below results in a
pay-back period of one year - depending on the price
per kWh and the price of the frequency converter.
m3/t
Distribution
Valve regulation
Frequency converter control
%
Hours
Power
Consumption
Power
Consumption
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
10,0
17.520
150
20
1752
28,0
49.056
6,5
11.388
100
20
1752
23,0
40.296
3,5
6.132
ΣΣΣΣΣ
100
100
100
100
100
8760
8760
8760
8760
8760
275.064
275.064
275.064
275.064
275.064
124.173
124.173
124.173
124.173
124.173
Pump characteristics
