Minimum Pressure Tank and Supply Pipe Sizing
A VFD system needs only a small pressure tank to maintain constant pressure, although a larger tank may
be used.
•
If adding a drive to a system with an existing large tank, refer to
ments" on page
26.
•
The pressure tank pre-charge setting should be 70% of the targeted system pressure.
Refer to the following recommendations for best performance.
Submersible Pump Applications
Pump Flow Rating
Less than 12 gpm (45.4 lpm)
12 gpm (45.4 lpm) and higher
Surface Pump Applications
Maximum Pump Flow
10 GPM
20 GPM
30 GPM
40 GPM
Minimum Supply Pipe Sizes
The minimum supply pipe diameter past the pressure sensor (transducer) should be selected not to exceed
a maximum velocity of 8 feet per second (2.4 m/s) based on the flow rate of the system.
IMPORTANT: Water system piping should be performed by an experienced professional to ensure adequate
flow.
Maximum GPM (lpm)
11.0 (41.6)
19.6 (74.2)
30.6 (115.8)
44.1 (166.9)
78.3 (296.4)
122.4 (463)
176.3 (667)
240.0 (908)
313.3 (1186)
396.6 (1501)
489.6 (1853)
Minimum Tank Size up to 1 HP
2 gallons (7.6 liters)
4 gallons (15.1 liters)
Minimum Tank Size
2 gallons (7.6 liters)
4 gallons (15.1 liters)
6
gallons (22.7 liters)
8 gallons (30.3 liters)
Minimum Pipe Diameter
0.75"
1"
1.25"
1.5"
2"
2.5"
3"
3.5"
4"
4.5"
5"
Minimum Pressure Tank and Supply Pipe Sizing
"Tank Size and Bump Mode Adjust-
Minimum Tank Size over 1 HP
4 gallons (15.1 liters)
8 gallons (30.3 liters)
INSTALLATION PLANNING
13