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100% speed
Flow
Flow
Pump curve
H
e
a
d
o
r
p
re
ssu
re
H
e
a
d
o
r
p
re
ssu
re
Natural
operating point
Operating
point
Th
ro
ttl
ed
Unt
hro
ttled
Th
ro
ttl
ed
syst
em
Un
thr
ott
led
syst
em
60 65
70
75
78
80
80
78
75
3
1
1
2
2
3
H
s
H
p
e
3
0
b
d
8
9
0
.1
0
Illustration 8: Flow Reduction by Valve Control (Throttling)
1
Operating point using a throttle valve
2
Natural operating point
3
Operating point using speed control
Speed control
The same flow can be adjusted by reducing the speed of the pump as shown in
. Reducing the speed moved the pump
curve down. The point of operation is the new intersection point of the pump curve and the system curve (3). The energy savings
can be calculated by applying the affinity laws as described in
4.3.1 Example of Energy Savings
.
Flow
H
e
a
d
o
r
P
re
ssu
re
Pump curve
Operating
point
Natural
Operating point
syst
em
Un
thro
ttle
d
Speed
reduction
1
2
3
H
p
Hs
e
3
0
b
d
8
9
4
.1
0
Illustration 9: Flow Reduction by Speed Control
AJ300847815559en-000101 / 130R0337
24 | Danfoss A/S © 2020.09
Product Family Overview
VLT® AQUA Drive FC 202
Design Guide