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System sizing
SQFlex
Sizing of SQFlex system
Grundfos has developed a PC-based sizing tool
enabling the sizing of SQFlex systems.
The sizing tool is also available in a paper version. The
PC-based sizing tool is integrated in WinCAPS and
covers both solar and wind powered systems. The
paper version covers both solar powered and wind
powered systems.
The following three parameters must be known for the
sizing of the optimum SQFlex system:
• installation location
• max. head required and
• quantity of water required.
With a view to the sizing of a correct solar powered
SQFlex system the world has been divided into six
regions:
• North America
• South America
• Australia/New Zealand
• Asia/Pacific
• Southern Africa
• Europe/Middle East/Northern Africa.
Each region is divided into a number of zones
according to the solar radiation in kWh/m
2
per day.
The following example shows the sizing of a solar
powered SQFlex system using the paper version of the
sizing tool.
For the sizing of a wind powered SQFlex system,
please refer to the WinCAPS version.
Example
Conditions:
• installation location: Austin, Texas
• required head: 220 ft
• quantity of water required: 1500 gal/day
Proceed as follows:
1. Find Austin, TX on the map.
The map shows that Austin is located in solar radia-
tion zone K, and the recommended tilt angle of the
solar panel is 30°.
2. Go to the sizing table and find zone K and tilt
angle 30°.
3. Find the required head (A) and the required flow (B)
and read the recommended SQF pump type (C),
number of solar modules (D) and the output power
of the solar modules (E).
SQFlex system configuration:
Pump: 6 SQF-2
Number of solar modules: 8
Power: 50 Wp x 8 = 400 Wp.
